AbstractComponent (zk 9.6.5 API)

java.lang.Object
- org.zkoss.zk.ui.AbstractComponent

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Component, Scope, ComponentCtrl

Direct Known Subclasses:

AbstractTag, Area, Fragment, HtmlBasedComponent, HtmlNativeComponent, HtmlShadowElement, NoDOM, Script, StubComponent, Style, Text, Transformer, XmlMacroComponent, XmlNativeComponent, Zkhead
```
public class AbstractComponent
extends java.lang.Object
implements Component, ComponentCtrl, java.io.Serializable
```
A skeletal implementation of Component.

Author:

tomyeh

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected class AbstractComponent.Children
The default implementation for getChildren().

Nested Classes
Modifier and Type	Class and Description
`protected class`	`AbstractComponent.Children` The default implementation for `getChildren()`.

Field Summary
- Fields inherited from interface org.zkoss.zk.ui.Component
  APPLICATION_SCOPE, COMPONENT_SCOPE, DESKTOP_SCOPE, PAGE_SCOPE, REQUEST_SCOPE, SESSION_SCOPE, SPACE_SCOPE
- Fields inherited from interface org.zkoss.zk.ui.sys.ComponentCtrl
  AFTER_CHILD_ADDED, AFTER_CHILD_REMOVED, AFTER_PAGE_ATTACHED, AFTER_PAGE_DETACHED, CE_BUSY_IGNORE, CE_DUPLICATE_IGNORE, CE_IMPORTANT, CE_NON_DEFERRABLE, CE_REPEAT_IGNORE

Constructor Summary

Constructors
Modifier	Constructor and Description
	`AbstractComponent()` Constructs a component with auto-generated ID.
`protected`	`AbstractComponent(boolean useless)` Constructs a dummy component that is not associated with any component definition.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`void`	`addAnnotation(java.lang.String annotName, java.util.Map<java.lang.String,java.lang.String[]> annotAttrs)` Deprecated. As of release 6.0.0, replaced with `addAnnotation(String, String, Map)`
`void`	`addAnnotation(java.lang.String propName, java.lang.String annotName, java.util.Map<java.lang.String,java.lang.String[]> annotAttrs)` Adds an annotation to the specified property of this component.
`boolean`	`addCallback(java.lang.String name, Callback callback)` Adds a callback at component in specific name
`protected static void`	`addClientEvent(java.lang.Class<? extends Component> cls, java.lang.String evtnm, int flags)` Adds an event that the client might send to the server.
`void`	`addEventHandler(java.lang.String name, EventHandler evthd)` Adds an event handler.
`boolean`	`addEventListener(int priority, java.lang.String evtnm, EventListener<? extends Event> listener)` Adds an event listener to specified event name for this component with the given priority.
`boolean`	`addEventListener(java.lang.String evtnm, EventListener<? extends Event> listener)` Adds an event listener to specified event name for this component.
`boolean`	`addForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent)` Adds a forward condition to forward the event received by this component to another component.
`boolean`	`addForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent, java.lang.Object eventData)` Adds a forward condition to forward the event received by this component to another component with extra event data.
`boolean`	`addForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent)` Adds a forward condition to forward the event received by this component to another component, specified with a path.
`boolean`	`addForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent, java.lang.Object eventData)` Adds a forward condition to forward the event received by this component to another component of the specified path with extra event data.
`protected void`	`addMoved(Component oldparent, Page oldpg, Page newpg)` Called when this component is moved from the specified parent and/or page to the new page.
`boolean`	`addRedrawCallback(Callback<ContentRenderer> callback)` Adds a callback at component redraw phase.
`boolean`	`addScopeListener(ScopeListener listener)` Adds a listener to listen whether this scope is changed.
`boolean`	`addShadowRoot(ShadowElement shadow)` Adds the given shadow root from this host.
`boolean`	`addShadowRootBefore(ShadowElement shadow, ShadowElement insertBefore)` Adds the given shadow root from this host.
`void`	`addSharedEventHandlerMap(EventHandlerMap evthds)` Adds a map of event handlers which is shared by other components.
`boolean`	`appendChild(Component child)` Appends a child to the end of all children.
`void`	`applyProperties()` Initializes the properties (a.k.a. members) based on what are defined in the component definition.
`void`	`beforeChildAdded(Component child, Component insertBefore)` Default: does nothing.
`void`	`beforeChildRemoved(Component child)` Default: does nothing.
`void`	`beforeParentChanged(Component parent)` Default: If parent is null, execute the @Destroy method if any.
`java.lang.Object`	`clone()` Clones the component.
`void`	`detach()` Detaches this component such that it won't belong to any page.
`protected void`	`didActivate(java.util.Collection<?> c)` Utility to invoke `ComponentActivationListener.didActivate(org.zkoss.zk.ui.Component)` for each object in the collection.
`protected void`	`didActivate(java.lang.Object o)` Utility to invoke `ComponentActivationListener.didActivate(org.zkoss.zk.ui.Component)` for the specified object.
`protected void`	`didDeserialize(java.util.Collection c)` Utility to invoke `ComponentSerializationListener.didDeserialize(org.zkoss.zk.ui.Component)` for each object in the collection.
`protected void`	`didDeserialize(java.lang.Object o)` Utility to invoke `ComponentSerializationListener.didDeserialize(org.zkoss.zk.ui.Component)` for the specified object.
`void`	`disableBindingAnnotation()` Set to disable the component with binding annotation.
`boolean`	`disableClientUpdate(boolean disable)` Sets whether to disable the update of the client widgets of this component and its descendants.
`void`	`enableBindingAnnotation()` Set to enable the component with binding annotation.
`java.util.List<java.lang.String>`	`getAnnotatedProperties()` Returns a read-only list of the name of properties that are associated at least one annotation (never null).
`java.util.List<java.lang.String>`	`getAnnotatedPropertiesBy(java.lang.String annotName)` Returns a read-only list of the names of the properties that are associated with the specified annotation (never null).
`Annotation`	`getAnnotation(java.lang.String annotName)` Deprecated. As of release 6.0.0, replaced with `getAnnotation(String, String)`.
`Annotation`	`getAnnotation(java.lang.String propName, java.lang.String annotName)` Returns the annotation associated with the definition of the specified property, or null if not available.
`java.util.Collection<Annotation>`	`getAnnotations()` Deprecated. As of release 6.0.0, replaced with `getAnnotations(String)`.
`java.util.Collection<Annotation>`	`getAnnotations(java.lang.String propName)` Returns a read-only collection of all annotations (`Annotation`) associated with the specified property.
`java.util.Collection<Annotation>`	`getAnnotations(java.lang.String propName, java.lang.String annotName)` Returns the annotations associated with the definition of the specified property.
`java.lang.Object`	`getAttribute(java.lang.String name)` Returns the custom attribute associated with this component, i.e., `Component.COMPONENT_SCOPE`.
`java.lang.Object`	`getAttribute(java.lang.String name, boolean recurse)` Returns the custom attribute associated with this object.
`java.lang.Object`	`getAttribute(java.lang.String name, int scope)` Returns the value of the specified custom attribute in the specified scope, or null if not defined.
`java.lang.Object`	`getAttributeOrFellow(java.lang.String name, boolean recurse)` Returns the custom attribute associated with this component, or the fellow of this component; or null if not found.
`java.util.Map<java.lang.String,java.lang.Object>`	`getAttributes()` Returns all custom attributes associated with this component, i.e., `Component.COMPONENT_SCOPE`.
`java.util.Map<java.lang.String,java.lang.Object>`	`getAttributes(int scope)` Returns all custom attributes of the specified scope.
`AuService`	`getAuService()` Returns an AU service to process the AU request before the component's default handling.
`java.lang.String`	`getAutag()` Returns the AU tag for this widget.
`java.util.Collection<Callback>`	`getCallback(java.lang.String name)` Returns all of callbacks by specific name
`<T extends Component> java.util.List<T>`	`getChildren()` Returns a live list of children.
`java.lang.String`	`getClientAttribute(java.lang.String name)` Returns the value of a DOM attribute
`java.lang.String`	`getClientDataAttribute(java.lang.String name)` Returns the value of a DOM data attribute Notice that the parameter - name would be expanded by adding the prefix "data-" automatically.
`java.util.Map<java.lang.String,java.lang.Integer>`	`getClientEvents()` Returns a map of event information that the client might send to this component.
`protected java.lang.String`	`getDefaultMold(java.lang.Class<? extends Component> klass)` Returns the default mold for the given class.
`ComponentDefinition`	`getDefinition()` Returns the component definition of this component (never null).
`Desktop`	`getDesktop()` Returns the desktop of this component, or null if this component doesn't belong to any desktop.
`ZScript`	`getEventHandler(java.lang.String evtnm)` Returns the event listener of the specified name, or null if not found.
`java.util.Set<java.lang.String>`	`getEventHandlerNames()` Returns a readonly collection of event names (String), or an empty collection if no event name is registered.
`EventListenerMap`	`getEventListenerMap()` Returns the map of event handlers and listeners defined in this component.
`java.lang.Iterable<EventListener<? extends Event>>`	`getEventListeners(java.lang.String evtnm)` Returns an iterable collection of the event listeners for the given event.
`java.lang.Object`	`getExtraCtrl()` Returns the extra controls that tell ZK how to handle this component specially.
`Component`	`getFellow(java.lang.String compId)` Returns a component of the specified ID in the same ID space.
`Component`	`getFellow(java.lang.String compId, boolean recurse)` Returns a component of the specified ID in the same ID space.
`Component`	`getFellowIfAny(java.lang.String compId)` Returns a component of the specified ID in the same ID space, or null if not found.
`Component`	`getFellowIfAny(java.lang.String compId, boolean recurse)` Returns a component of the specified ID in the same ID space, or null if not found.
`java.util.Collection<Component>`	`getFellows()` Returns all fellows in the same ID space of this component.
`Component`	`getFirstChild()` Returns the first child component, or null if no child at all.
`java.lang.String`	`getId()` Returns the ID.
`Component`	`getLastChild()` Returns the last child component, or null if no child at all.
`java.util.Iterator<EventListener<? extends Event>>`	`getListenerIterator(java.lang.String evtnm)` Deprecated. As of release 6.0, replaced with `getEventListeners(java.lang.String)`.
`java.lang.String`	`getMold()` Returns the mold used to render this component.
`Component`	`getNextSibling()` Returns the next sibling, or null if it is the last child.
`Page`	`getPage()` Returns the page that this component belongs to, or null if it doesn't belong to any page.
`Component`	`getParent()` Returns the parent component, or null if this is the root component.
`Component`	`getPreviousSibling()` Returns the previous sibling, or null if it is the first child.
`PropertyAccess`	`getPropertyAccess(java.lang.String prop)` Returns the corresponding property access object from the given property name, if any.
`java.util.Collection<Callback<ContentRenderer>>`	`getRedrawCallback()` Returns all of callbacks for component redraw phase
`Component`	`getRoot()` Returns the root of the specified component.
`ShadowElement`	`getShadowFellowIfAny(java.lang.String id)` Returns the shadow element under this shadow host.
`<T extends ShadowElement> java.util.List<T>`	`getShadowRoots()` Returns a set of shadow elements, if any.
`java.lang.Object`	`getShadowVariable(Component baseChild, java.lang.String name, boolean recurse)` Returns the shadow variable enclosed with the base component, which associated with this component or its parent component; or null if not found.
`java.lang.Object`	`getShadowVariable(java.lang.String name, boolean recurse)` Returns the shadow variable associated with this component or its parent component; or null if not found.
`protected java.lang.Object`	`getShadowVariable0(Component baseChild, java.lang.String name, boolean recurse)`
`IdSpace`	`getSpaceOwner()` Returns the owner of the ID space that this component belongs to.
`protected java.lang.String`	`getSpecialRendererOutput(Component comp)`
`java.lang.String`	`getStubonly()` Returns whether this component is stub-only.
`int`	`getSubBindingAnnotationCount()` Returns the count of the component's subtree binding annotation.
`Template`	`getTemplate(java.lang.String name)` Returns the template of the given name, or null if not available.
`java.util.Set<java.lang.String>`	`getTemplateNames()` Returns a readonly set of the names of all templates.
`java.lang.String`	`getUuid()` Returns UUID (universal unique ID) which is unique in the whole session.
`java.lang.String`	`getWidgetAttribute(java.lang.String name)`
`java.util.Set<java.lang.String>`	`getWidgetAttributeNames()` Returns a read-only collection of additions DOM attributes that shall be generated.
`java.lang.String`	`getWidgetClass()` Returns the widget class (a.k.a., widget type), or null if not defined.
`java.lang.String`	`getWidgetListener(java.lang.String evtnm)` Returns the script of the client event, or null if not found.
`java.util.Set<java.lang.String>`	`getWidgetListenerNames()` Returns a read-only collection of event names (String) that the listener of the peer widget are assigned, or an empty collection if none is registered.
`java.lang.String`	`getWidgetOverride(java.lang.String name)` Returns the script of the method definition to override widget's method, or null if not found.
`java.util.Set<java.lang.String>`	`getWidgetOverrideNames()` Returns a read-only collection of the property names (String) that shall be overridden, or an empty collection if none is registered.
`boolean`	`hasAttribute(java.lang.String name)` Returns if the custom attribute is associate with this component.
`boolean`	`hasAttribute(java.lang.String name, boolean recurse)` Returns if a custom attribute is associated with this object.
`boolean`	`hasAttribute(java.lang.String name, int scope)` Returns if the custom attribute is associate with this component.
`boolean`	`hasAttributeOrFellow(java.lang.String name, boolean recurse)` Returns if a custom attribute is associated with this component, or the fellow of this component.
`boolean`	`hasBindingAnnotation()` Returns whether the component itself has binding annotation or not.
`boolean`	`hasFellow(java.lang.String compId)` Returns whether a fellow exists in the same ID space of this component.
`boolean`	`hasFellow(java.lang.String compId, boolean recurse)` Returns whether there is a fellow named with the specified component ID in the same ID space as this component.
`boolean`	`hasSubBindingAnnotation()` Returns whether the component and its children have binding annotation or not.
`boolean`	`insertBefore(Component newChild, Component refChild)` Inserts a child before the reference child.
`void`	`invalidate()` Invalidates this component by setting the dirty flag such that it will be redraw the whole content of this component and its dependencies later.
`void`	`invalidatePartial()` Invalidates this component by setting the dirty flag such that it will be redraw the partial content of this component and its dependencies later.
`protected boolean`	`isChildable()` Returns whether this component can have a child.
`boolean`	`isInitialized()` Returns if it's finished layout phase (initializing).
`boolean`	`isInvalidated()` Returns if this component needs to be redrawn at the client.
`boolean`	`isListenerAvailable(java.lang.String evtnm, boolean asap)` Returns whether the event listener is available.
`boolean`	`isVisible()` Returns whether this component is visible.
`void`	`onChildAdded(Component child)` Default: handles special event listeners.
`void`	`onChildRemoved(Component child)` Default: handles special event listeners.
`void`	`onPageAttached(Page newpage, Page oldpage)` Default: handles special event listeners.
`void`	`onPageDetached(Page page)` Default: handles special event listeners.
`WrongValueException`	`onWrongValue(WrongValueException ex)` Notifies that an `WrongValueException` instance is thrown, and `WrongValueException.getComponent()` is this component.
`Component`	`query(java.lang.String selector)` Find the first component that matches the given CSS3 selector.
`java.lang.Iterable<Component>`	`queryAll(java.lang.String selector)` Returns an iterable object for components that match the given CSS3 selector.
`void`	`redraw(java.io.Writer out)` Redraws this component and all its descendants.
`protected void`	`redrawChildren(java.io.Writer out)` Redraws children (and then recursively descendants).
`java.lang.Object`	`removeAttribute(java.lang.String name)` Removes the custom attribute associated with this component, i.e., `Component.COMPONENT_SCOPE`.
`java.lang.Object`	`removeAttribute(java.lang.String name, boolean recurse)` Removes the custom attribute associated with this scope.
`java.lang.Object`	`removeAttribute(java.lang.String name, int scope)` Removes the specified custom attribute in the specified scope.
`boolean`	`removeCallback(java.lang.String name, Callback callback)` Removes a callback for component by specific name.
`boolean`	`removeChild(Component child)` Removes a child.
`boolean`	`removeEventListener(java.lang.String evtnm, EventListener<? extends Event> listener)` Removes an event listener.
`boolean`	`removeForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent)` Removes a forward condition that was added by `Component.addForward(String, Component, String)`.
`boolean`	`removeForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent)` Removes a forward condition that was added by `Component.addForward(String, String, String)`.
`boolean`	`removeRedrawCallback(Callback<ContentRenderer> callback)` Removes a callback for component redraw phase.
`boolean`	`removeScopeListener(ScopeListener listener)` Removes a change listener from this scope.
`boolean`	`removeShadowRoot(ShadowElement shadow)` Removes the given shadow root from this host.
`protected void`	`render(ContentRenderer renderer, java.lang.String name, boolean value)` An utility to be called by `renderProperties(org.zkoss.zk.ui.sys.ContentRenderer)` to render a boolean-value property if it is true.
`protected void`	`render(ContentRenderer renderer, java.lang.String name, java.lang.Object value)` An utility to be called by `renderProperties(org.zkoss.zk.ui.sys.ContentRenderer)` to render a string-value property.
`protected void`	`render(ContentRenderer renderer, java.lang.String name, java.lang.String value)` An utility to be called by `renderProperties(org.zkoss.zk.ui.sys.ContentRenderer)` to render a string-value property.
`protected void`	`renderProperties(ContentRenderer renderer)` Called by (`ComponentCtrl.redraw(java.io.Writer)`) to render the properties, excluding the enclosing tag and children.
`protected void`	`replace(Component comp, boolean bFellow, boolean bListener, boolean bChildren)` Replace the specified component with this component in the component tree.
`protected void`	`response(AuResponse response)` Causes a response to be sent to the client.
`protected void`	`response(java.lang.String key, AuResponse response)` Causes a response to be sent to the client by overriding the key returned by `AuResponse.getOverrideKey()`).
`protected void`	`response(java.lang.String key, AuResponse response, int priority)` Causes a response to be sent to the client by overriding the key returned by `AuResponse.getOverrideKey()`).
`void`	`service(AuRequest request, boolean everError)` Handles an AU request.
`void`	`service(Event event, Scope scope)` Handles an event.
`void`	`sessionDidActivate(Page page)` Notification that the session, which owns this component, has just been activated (a.k.a., deserialized).
`void`	`sessionWillPassivate(Page page)` Notification that the session, which owns this component, is about to be passivated (a.k.a., serialized).
`java.lang.Object`	`setAttribute(java.lang.String name, java.lang.Object value)` Sets the custom attribute associated with this component, i.e., `Component.COMPONENT_SCOPE`.
`java.lang.Object`	`setAttribute(java.lang.String name, java.lang.Object value, boolean recurse)` Sets the custom attribute associated with this scope, or the parent scope.
`java.lang.Object`	`setAttribute(java.lang.String name, java.lang.Object value, int scope)` Sets the value of the specified custom attribute in the specified scope.
`void`	`setAuService(AuService ausvc)` Sets an AU service to process the AU request before the component's default handling.
`void`	`setAutag(java.lang.String tag)` Sets the AU tag for this widget.
`java.lang.String`	`setClientAttribute(java.lang.String name, java.lang.String value)` Sets or removes a DOM attribute of the peer widget (at the client).
`java.lang.String`	`setClientDataAttribute(java.lang.String name, java.lang.String value)` Sets a DOM data attribute of the peer widget (at the client).
`void`	`setDefinition(ComponentDefinition compdef)` Sets the component definition.
`void`	`setDefinition(java.lang.String name)` Sets the component definition by specifying the name.
`void`	`setId(java.lang.String id)` Sets the ID.
`void`	`setMold(java.lang.String mold)` Sets the mold to render this component.
`void`	`setPage(Page page)` Sets what page this component belongs to.
`void`	`setPageBefore(Page page, Component refRoot)` Sets what page this component belongs to, and insert this component right before the reference component.
`void`	`setParent(Component parent)` Sets the parent component.
`void`	`setStubonly(boolean stubonly)` Sets whether this component is stub-only.
`void`	`setStubonly(java.lang.String stubonly)` Sets whether this component is stub-only.
`protected void`	`setSubBindingAnnotationCount(int diff, AbstractComponent node)`
`Template`	`setTemplate(java.lang.String name, Template template)` Sets a UI template which could be retrieved later with `Component.getTemplate(java.lang.String)`.
`boolean`	`setVisible(boolean visible)` Sets whether this component is visible.
`protected void`	`setVisibleDirectly(boolean visible)` Changes the visibility directly without sending any update to the client.
`java.lang.String`	`setWidgetAttribute(java.lang.String name, java.lang.String value)`
`void`	`setWidgetClass(java.lang.String wgtcls)` Sets the widget class (a.k.a., the widget type).
`java.lang.String`	`setWidgetListener(java.lang.String evtnm, java.lang.String script)` Sets or removes an event listener of the peer widget.
`java.lang.String`	`setWidgetOverride(java.lang.String name, java.lang.String script)` Sets or removes a method or a property of the peer widget (at the client).
`protected void`	`smartUpdate(java.lang.String attr, boolean value)` A special smart update to update a value in boolean.
`protected void`	`smartUpdate(java.lang.String attr, byte value)` A special smart update to update a value in byte.
`protected void`	`smartUpdate(java.lang.String attr, char value)` A special smart update to update a value in character.
`protected void`	`smartUpdate(java.lang.String attr, double value)` A special smart update to update a value in double.
`protected void`	`smartUpdate(java.lang.String attr, float value)` A special smart update to update a value in float.
`protected void`	`smartUpdate(java.lang.String attr, int value)` A special smart update to update a value in int.
`protected void`	`smartUpdate(java.lang.String attr, long value)` A special smart update to update a value in long.
`protected void`	`smartUpdate(java.lang.String attr, java.lang.Object value)` Smart-updates a property of the peer widget associated with the component, running at the client, with the given value.
`protected void`	`smartUpdate(java.lang.String attr, java.lang.Object value, boolean append)` Smart-updates a property of the peer widget with the given value that allows caller to decide whether to append or overwrite.
`protected void`	`smartUpdateWidgetListener(java.lang.String evtnm, java.lang.String script)` A special smart update to update an event listener for the peer widget.
`protected void`	`smartUpdateWidgetOverride(java.lang.String name, java.lang.String script)` A special smart update to update a method or a field of the peer widget.
`java.lang.String`	`toString()`
`protected void`	`updateByClient(java.lang.String name, java.lang.Object value)` Called when the widget running at the client asks the server to update a value.
`protected void`	`updateSubBindingAnnotationCount(int diff)`
`protected void`	`willPassivate(java.util.Collection<?> c)` Utility to invoke `ComponentActivationListener.willPassivate(org.zkoss.zk.ui.Component)` for each object in the collection.
`protected void`	`willPassivate(java.lang.Object o)` Utility to invoke `ComponentActivationListener.willPassivate(org.zkoss.zk.ui.Component)` for the specified object.
`protected void`	`willSerialize(java.util.Collection c)` Utility to invoke `ComponentSerializationListener.willSerialize(org.zkoss.zk.ui.Component)` for each object in the collection.
`protected void`	`willSerialize(java.lang.Object o)` Utility to invoke `ComponentSerializationListener.willSerialize(org.zkoss.zk.ui.Component)` for the specified object.

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.zkoss.zk.ui.sys.ComponentCtrl
invalidatePartial

- Constructor Detail
  - AbstractComponent
```
public AbstractComponent()
```
    Constructs a component with auto-generated ID.
    
    Since:
    
    3.0.7 (becomes public)
  - AbstractComponent
```
protected AbstractComponent(boolean useless)
```
    Constructs a dummy component that is not associated with any component definition.
    
    Parameters:
    
    useless - an useless argument (it is ignored but used to distinguish the default constructor)
    
    Since:
    
    6.0.0
- Method Detail
  - getPage
```
public Page getPage()
```
    Description copied from interface: Component
    
    Returns the page that this component belongs to, or null if it doesn't belong to any page.
    When a component is created (a.k.a., constructed), it doesn't belong to any page. And, if a component doesn't belong to any page, they won't be displayed at the client.
    When changing parent (Component.setParent(org.zkoss.zk.ui.Component)), the child component's page will become the same as parent's. In other words, a component is added to a page automatically if it becomes a child of another component (who belongs to a page).
    For root components, you have to invoke Component.setPage(org.zkoss.zk.ui.Page) Explicitly.
    
    Specified by:
    
    getPage in interface Component
    
    See Also:
    
    Component.setParent(org.zkoss.zk.ui.Component), Component.setPage(org.zkoss.zk.ui.Page)
  - getDesktop
```
public Desktop getDesktop()
```
    Description copied from interface: Component
    Returns the desktop of this component, or null if this component doesn't belong to any desktop.
    When a component is created in an event listener, it is assigned to the current desktop automatically. If a component is created not in any event listener, it doesn't belong to any desktop and this method returns null. Once a component is attached to a desktop (by use of Component.setPage(org.zkoss.zk.ui.Page) or Component.setParent(org.zkoss.zk.ui.Component)), it belongs to the desktop.
    Notice: there is no way to detach a component from a desktop, once it is attached as described above. In other words, you cannot move a component (or page) from one desktop to another.
    In summary, there are only two ways to handle components.
    1. Handle them all in event listeners and don't access any components from other desktops. This is simplest and clearest.
    2. Creates components in another thread (other than event listener) and attach them to a page (and then desktop) upon an event is received.
    Specified by:
    
    getDesktop in interface Component
  - setPage
```
public void setPage(Page page)
```
    Description copied from interface: Component
    
    Sets what page this component belongs to. If this component already belongs to the same page, nothing is changed.
    For child components, the page they belong is maintained automatically. You need to invoke this method only for root components.
    Note: a component might be attached to a page due invocations other than this method. For example, a component is attached if its parent is attached. To know whether it is attached, override ComponentCtrl.onPageAttached(org.zkoss.zk.ui.Page, org.zkoss.zk.ui.Page) rather than this method.
    If you would like to monitor if a component is attached or detached from a page, you could register a desktop listener implementing UiLifeCycle.
    
    Specified by:
    
    setPage in interface Component
    
    See Also:
    
    ComponentCtrl.onPageAttached(org.zkoss.zk.ui.Page, org.zkoss.zk.ui.Page), ComponentCtrl.onPageDetached(org.zkoss.zk.ui.Page)
  - setPageBefore
```
public void setPageBefore(Page page,
                          Component refRoot)
```
    Description copied from interface: Component
    
    Sets what page this component belongs to, and insert this component right before the reference component.
    For child components, the page they belong is maintained automatically. You need to invoke this method only for root components.
    It is similar to Component.setPage(org.zkoss.zk.ui.Page), except this component will be placed before the reference component. If the reference component is null, this component is placed at the end of all root components.
    
    Specified by:
    
    setPageBefore in interface Component
    
    refRoot - another root component used as a reference which this component will be placed before. If null, this component will be placed at the end of all root components (no matter whether it already belongs to the same page).
    
    See Also:
    
    Component.setPage(org.zkoss.zk.ui.Page)
  - addMoved
```
protected void addMoved(Component oldparent,
                        Page oldpg,
                        Page newpg)
```
    Called when this component is moved from the specified parent and/or page to the new page.
    Default: it notifies UiEngine to update the component at the client (usually remove-and-add).
    It is designed to let derived classes overriding this method to disable this update. However, you rarely need to override it. One possible but rare case: the component's visual part at the client updates the visual representation at the client and then notify the component at the server to update its children accordingly. In this case, it is redundant if we ask UI Engine to send the updates to client.
    
    Parameters:
    
    oldparent - the parent before moved. The new parent can be found by calling getParent().
    
    oldpg - the parent before moved.
    
    newpg - the new page. getPage() might return the old page.
  - getId
```
public java.lang.String getId()
```
    Description copied from interface: Component
    
    Returns the ID.
    Default: "" (an empty string; it means no ID at all).
    If a component belongs to an ID space (see IdSpace), the ID must also be unique in the ID space it belongs. any its parent and ancestor implements IdSpace. If it is a root component (i.e., without any parent), its ID must be unique among root components of the same page.
    A page itself is also an ID space, so you could retrieve components in a page by use of IdSpace.getFellow(java.lang.String), unless the component is a descendant of another component that implements IdSpace. In this case, you have to retrieve the parent first (by use of IdSpace.getFellow(java.lang.String) and then use Component.getFellow(java.lang.String) against the owner of the ID space.
    In zscript and EL, a component with explicit ID can be accessed directly by the ID.
    
    Specified by:
    
    getId in interface Component
    
    See Also:
    
    Path
  - setId
```
public void setId(java.lang.String id)
```
    Description copied from interface: Component
    
    Sets the ID. The scope of uniqueness depends on whether this component is a root component. Refer to Component.getId() for more details.
    Default: "" (an empty string; it means no ID at all).
    
    Specified by:
    
    setId in interface Component
    
    Parameters:
    
    id - the identifier. You could specify null or an empty string to remove ID.
    
    See Also:
    
    Selectors
  - getUuid
```
public java.lang.String getUuid()
```
    Description copied from interface: Component
    
    Returns UUID (universal unique ID) which is unique in the whole session. The UUID is generated automatically and immutable, unless RawId is also implemented.
    It is mainly used for communication between client and server and you rarely need to access it.
    If RawId is implemented as part of a component, UUID is the same as Component.getId() if Component.setId(java.lang.String) is ever called. It is designed to migrate HTML pages to ZK, such that the element ID could remain the same.
    
    Specified by:
    
    getUuid in interface Component
  - getSpaceOwner
```
public IdSpace getSpaceOwner()
```
    Description copied from interface: Component
    
    Returns the owner of the ID space that this component belongs to. The returned value could be a component, a page or null. If this component itself implements IdSpace, this method returns itself. If it has an ancestor that implements IdSpace, the ancestor is returned. Otherwise, the page it belongs to is returned
    Each ID space defines an independent set of IDs. No component in the same ID space could have the same ID. To get any component in the same ID space, you could use Component.getFellow(java.lang.String). See IdSpace for more details.
    The ID space related methods include Component.getFellow(java.lang.String), Component.getAttribute(java.lang.String, int) and Component.getAttributeOrFellow(java.lang.String, boolean).
    
    Specified by:
    
    getSpaceOwner in interface Component
  - hasFellow
```
public boolean hasFellow(java.lang.String compId)
```
    Description copied from interface: Component
    
    Returns whether a fellow exists in the same ID space of this component.
    
    Specified by:
    
    hasFellow in interface Component
  - hasFellow
```
public boolean hasFellow(java.lang.String compId,
                         boolean recurse)
```
    Description copied from interface: Component
    
    Returns whether there is a fellow named with the specified component ID in the same ID space as this component. It is the same as getSpaceOwner().hasFellow(id, recurse);
    
    Specified by:
    
    hasFellow in interface Component
    
    recurse - whether to look up the parent ID space for the existence of the fellow
  - getFellow
```
public Component getFellow(java.lang.String compId)
                    throws ComponentNotFoundException
```
    Description copied from interface: Component
    
    Returns a component of the specified ID in the same ID space. Components in the same ID space assigned with ID are called fellows.
    Unlike Component.getFellowIfAny(java.lang.String), it throws an exception if not found.
    
    Specified by:
    
    getFellow in interface Component
    
    Throws:
    
    ComponentNotFoundException - is thrown if fellow not found
  - getFellow
```
public Component getFellow(java.lang.String compId,
                           boolean recurse)
                    throws ComponentNotFoundException
```
    Description copied from interface: Component
    
    Returns a component of the specified ID in the same ID space. It is the same as getSpaceOwner().getFellow(id, recurse);
    Unlike Component.getFellowIfAny(String, boolean), it throws ComponentNotFoundException if not found.
    
    Specified by:
    
    getFellow in interface Component
    
    recurse - whether to look up the parent ID space for the existence of the fellow
    
    Throws:
    
    ComponentNotFoundException - is thrown if this component doesn't belong to any ID space
  - getFellowIfAny
```
public Component getFellowIfAny(java.lang.String compId)
```
    Description copied from interface: Component
    
    Returns a component of the specified ID in the same ID space, or null if not found.
    Unlike Component.getFellow(java.lang.String), it returns null if not found.
    
    Specified by:
    
    getFellowIfAny in interface Component
  - getFellowIfAny
```
public Component getFellowIfAny(java.lang.String compId,
                                boolean recurse)
```
    Description copied from interface: Component
    
    Returns a component of the specified ID in the same ID space, or null if not found. It is the same as getSpaceOwner().getFellowIfAny(id, recurse);
    Unlike Component.getFellow(String, boolean), it returns null if not found.
    
    Specified by:
    
    getFellowIfAny in interface Component
    
    recurse - whether to look up the parent ID space for the existence of the fellow
  - getFellows
```
public java.util.Collection<Component> getFellows()
```
    Description copied from interface: Component
    
    Returns all fellows in the same ID space of this component. Notice that only components that are assigned with ID are considered as fellows. The returned collection is read-only.
    
    Specified by:
    
    getFellows in interface Component
  - getNextSibling
```
public Component getNextSibling()
```
    Description copied from interface: Component
    
    Returns the next sibling, or null if it is the last child.
    
    Specified by:
    
    getNextSibling in interface Component
  - getPreviousSibling
```
public Component getPreviousSibling()
```
    Description copied from interface: Component
    
    Returns the previous sibling, or null if it is the first child.
    
    Specified by:
    
    getPreviousSibling in interface Component
  - getFirstChild
```
public Component getFirstChild()
```
    Description copied from interface: Component
    
    Returns the first child component, or null if no child at all.
    
    Specified by:
    
    getFirstChild in interface Component
  - getLastChild
```
public Component getLastChild()
```
    Description copied from interface: Component
    
    Returns the last child component, or null if no child at all.
    
    Specified by:
    
    getLastChild in interface Component
  - setWidgetListener
```
public java.lang.String setWidgetListener(java.lang.String evtnm,
                                          java.lang.String script)
```
    Description copied from interface: Component
    
    Sets or removes an event listener of the peer widget. If there is an event listener associated with the same event, the previous one will be replaced and returned.
    
    Specified by:
    
    setWidgetListener in interface Component
    
    Parameters:
    
    evtnm - the event name, such as onClick
    
    script - the script to handle the event. If null, the event handler is removed.
    
    Returns:
    
    the previous script if any
  - getWidgetListener
```
public java.lang.String getWidgetListener(java.lang.String evtnm)
```
    Description copied from interface: Component
    
    Returns the script of the client event, or null if not found.
    
    Specified by:
    
    getWidgetListener in interface Component
  - getWidgetListenerNames
```
public java.util.Set<java.lang.String> getWidgetListenerNames()
```
    Description copied from interface: Component
    
    Returns a read-only collection of event names (String) that the listener of the peer widget are assigned, or an empty collection if none is registered.
    
    Specified by:
    
    getWidgetListenerNames in interface Component
  - setWidgetOverride
```
public java.lang.String setWidgetOverride(java.lang.String name,
                                          java.lang.String script)
```
    Description copied from interface: Component
    Sets or removes a method or a property of the peer widget (at the client). If there is a method or a property associated with the same name, the previous one will be replaced and returned.
    For example,
```
comp.setWidgetOverride("setValue", "function (value) {}"); //override a method
comp.setWidgetOverride("myfield", "new Date()"); //override a property
```
    If there is no previous method or property, the method/property will be assigned directly.
    Notice that, unlike Component.setWidgetListener(java.lang.String, java.lang.String), if the method has been sent to the client for update, it cannot be removed by calling this method with a null value. In other words, invoking this method with a null value only removes the method overrides if it has not YET been to sent to the client.
    The previous method/property can be accessed by this.$xxx. For example
```
function (value, fromServer) {
  this.$setValue(value, fromServer);
  if (this.desktop) {
    this._cnt = !this._cnt;
    this.setStyle('background:'+(this._cnt ? 'red':'green'));
  }
}
```
    Notice that, since it is not extending, so this.$super references the superclass's method, rather than the old method.
    Specified by:
    
    setWidgetOverride in interface Component
    
    Parameters:
    
    name - the property name to override, such as setValue and miles.
    script - the method definition, such as function (arg) {...}, or a value, such as 123 and new Date(). If not null, this method will be added to the peer widget. If there was a method with the same name, it will be renamed to $name so can you call it back.
    <label w:setValue="function (value) { this.$setValue(value); //old method }"/>
    If null, the previous method, if any, will be restored.
    Returns:
    
    the previous script if any
  - getWidgetOverride
```
public java.lang.String getWidgetOverride(java.lang.String name)
```
    Description copied from interface: Component
    
    Returns the script of the method definition to override widget's method, or null if not found.
    
    Specified by:
    
    getWidgetOverride in interface Component
  - getWidgetOverrideNames
```
public java.util.Set<java.lang.String> getWidgetOverrideNames()
```
    Description copied from interface: Component
    
    Returns a read-only collection of the property names (String) that shall be overridden, or an empty collection if none is registered.
    
    Specified by:
    
    getWidgetOverrideNames in interface Component
  - setWidgetAttribute
```
public java.lang.String setWidgetAttribute(java.lang.String name,
                                           java.lang.String value)
```
    Specified by:
    
    setWidgetAttribute in interface Component
  - setClientAttribute
```
public java.lang.String setClientAttribute(java.lang.String name,
                                           java.lang.String value)
```
    Description copied from interface: Component
    
    Sets or removes a DOM attribute of the peer widget (at the client). ZK pass the attributes directly to the DOM attribute generated at the client.
    Notice that Component.setWidgetOverride(java.lang.String, java.lang.String) or Component.setWidgetListener(java.lang.String, java.lang.String) are used to customize the peer widget, while Component.setWidgetAttribute(java.lang.String, java.lang.String) customizes the DOM element of the peer widget directly.
    Unlike Component.setWidgetOverride(java.lang.String, java.lang.String) or Component.setWidgetListener(java.lang.String, java.lang.String), Component.setWidgetAttribute(java.lang.String, java.lang.String) has no effect if the widget has been generated at the client, unless Component.invalidate() is called.
    
    Specified by:
    
    setClientAttribute in interface Component
    
    Parameters:
    
    name - the attribute name to generate to the DOM element, such as onload. Unlike Component.setWidgetOverride(java.lang.String, java.lang.String), the name might contain no alphanumeric characters, such as colon and dash.
    
    value - the value of the attribute. It could be anything depending on the attribute. If null, the attribute will be removed. Make sure to specify an empty string if you want an attribute with an empty value.
    
    Returns:
    
    the previous value if any
  - getWidgetAttribute
```
public java.lang.String getWidgetAttribute(java.lang.String name)
```
    Specified by:
    
    getWidgetAttribute in interface Component
  - getClientAttribute
```
public java.lang.String getClientAttribute(java.lang.String name)
```
    Description copied from interface: Component
    
    Returns the value of a DOM attribute
    
    Specified by:
    
    getClientAttribute in interface Component
  - getWidgetAttributeNames
```
public java.util.Set<java.lang.String> getWidgetAttributeNames()
```
    Description copied from interface: Component
    
    Returns a read-only collection of additions DOM attributes that shall be generated. That is, they are the attributes added by Component.setWidgetAttribute(java.lang.String, java.lang.String).
    
    Specified by:
    
    getWidgetAttributeNames in interface Component
  - setClientDataAttribute
```
public java.lang.String setClientDataAttribute(java.lang.String name,
                                               java.lang.String value)
```
    Description copied from interface: Component
    
    Sets a DOM data attribute of the peer widget (at the client). If it has previous value, the component will invalidate. ZK pass the attributes directly to the DOM attribute generated at the client.
    Notice that the parameter - name would be expanded by adding the prefix "data-" automatically.
    
    Specified by:
    
    setClientDataAttribute in interface Component
    
    Parameters:
    
    name - the attribute name to generate to the DOM element, such as mask.
    
    value - the value of the attribute. It could be anything depending on the attribute. If null, the attribute will be removed. Make sure to specify an empty string if you want an attribute with an empty value.
    
    Returns:
    
    the previous value if any
    
    See Also:
    
    Component.setClientDataAttribute(String, String)
  - getClientDataAttribute
```
public java.lang.String getClientDataAttribute(java.lang.String name)
```
    Description copied from interface: Component
    
    Returns the value of a DOM data attribute
    Notice that the parameter - name would be expanded by adding the prefix "data-" automatically.
    
    Specified by:
    
    getClientDataAttribute in interface Component
    
    See Also:
    
    Component.getClientDataAttribute(String)
  - getAttributes
```
public java.util.Map<java.lang.String,java.lang.Object> getAttributes(int scope)
```
    Description copied from interface: Component
    
    Returns all custom attributes of the specified scope. You could reference them by use of componentScope, spaceScope, pageScope, requestScope and desktopScope in zscript and EL.
    If scope is Component.COMPONENT_SCOPE, it means custom attributes private to this component.
    If scope is Component.SPACE_SCOPE, it means custom attributes shared by components from the same ID space as this one's.
    If scope is Component.PAGE_SCOPE, it means custom attributes shared by components from the same page as this one's.
    If scope is Component.DESKTOP_SCOPE, it means custom attributes shared by components from the same desktops this one's.
    
    Specified by:
    
    getAttributes in interface Component
    
    Parameters:
    
    scope - one of Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE or Component.APPLICATION_SCOPE,
  - getAttributes
```
public java.util.Map<java.lang.String,java.lang.Object> getAttributes()
```
    Description copied from interface: Component
    
    Returns all custom attributes associated with this component, i.e., Component.COMPONENT_SCOPE.
    
    Specified by:
    
    getAttributes in interface Component
    
    Specified by:
    
    getAttributes in interface Scope
  - getAttribute
```
public java.lang.Object getAttribute(java.lang.String name,
                                     int scope)
```
    Description copied from interface: Component
    
    Returns the value of the specified custom attribute in the specified scope, or null if not defined.
    If scope is Component.COMPONENT_SCOPE, it means attributes private to this component.
    If scope is Component.SPACE_SCOPE, it means custom attributes shared by components from the same ID space as this one's.
    If scope is Component.PAGE_SCOPE, it means custom attributes shared by components from the same page as this one's.
    If scope is Component.DESKTOP_SCOPE, it means custom attributes shared by components from the same desktop as this one's.
    
    Specified by:
    
    getAttribute in interface Component
    
    scope - one of Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE or Component.APPLICATION_SCOPE,
  - getAttribute
```
public java.lang.Object getAttribute(java.lang.String name)
```
    Description copied from interface: Component
    
    Returns the custom attribute associated with this component, i.e., Component.COMPONENT_SCOPE.
    
    Specified by:
    
    getAttribute in interface Component
    
    Specified by:
    
    getAttribute in interface Scope
  - getAttribute
```
public java.lang.Object getAttribute(java.lang.String name,
                                     boolean recurse)
```
    Description copied from interface: Scope
    
    Returns the custom attribute associated with this object.
    
    Specified by:
    
    getAttribute in interface Scope
    
    recurse - whether to search its ancestor scope. If true and the current scope doen't define the attribute, it searches up its ancestor to see any of them has defined the specified attribute.
  - hasAttribute
```
public boolean hasAttribute(java.lang.String name,
                            int scope)
```
    Description copied from interface: Component
    
    Returns if the custom attribute is associate with this component.
    If scope is Component.COMPONENT_SCOPE, it means attributes private to this component.
    If scope is Component.SPACE_SCOPE, it means custom attributes shared by components from the same ID space as this one's.
    If scope is Component.PAGE_SCOPE, it means custom attributes shared by components from the same page as this one's.
    If scope is Component.DESKTOP_SCOPE, it means custom attributes shared by components from the same desktop as this one's.
    Notice that null is a valid value, so you can tell if an attribute is associated by examining the return value of Component.getAttribute(java.lang.String, int).
    
    Specified by:
    
    hasAttribute in interface Component
    
    scope - one of Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE or Component.APPLICATION_SCOPE,
  - hasAttribute
```
public boolean hasAttribute(java.lang.String name)
```
    Description copied from interface: Component
    
    Returns if the custom attribute is associate with this component.
    Notice that null is a valid value, so you can tell if an attribute is associated by examining the return value of Component.getAttribute(java.lang.String, int).
    
    Specified by:
    
    hasAttribute in interface Component
    
    Specified by:
    
    hasAttribute in interface Scope
  - hasAttribute
```
public boolean hasAttribute(java.lang.String name,
                            boolean recurse)
```
    Description copied from interface: Scope
    
    Returns if a custom attribute is associated with this object.
    Notice that null is a valid value, so you can tell if an attribute is associated by examining the return value of Scope.getAttribute(java.lang.String).
    
    Specified by:
    
    hasAttribute in interface Scope
    
    recurse - whether to search its ancestor scope. If true and the current scope doen't define the attribute, it searches up its ancestor to see any of them has defined the specified attribute.
  - setAttribute
```
public java.lang.Object setAttribute(java.lang.String name,
                                     java.lang.Object value,
                                     int scope)
```
    Description copied from interface: Component
    
    Sets the value of the specified custom attribute in the specified scope.
    Note: The attribute is removed (by Component.removeAttribute(java.lang.String, int) if value is null.
    If scope is Component.COMPONENT_SCOPE, it means custom attributes private to this component.
    If scope is Component.SPACE_SCOPE, it means custom attributes shared by components from the same ID space as this one's.
    If scope is Component.PAGE_SCOPE, it means custom attributes shared by components from the same page as this one's.
    If scope is Component.DESKTOP_SCOPE, it means custom attributes shared by components from the same desktop as this one's.
    
    Specified by:
    
    setAttribute in interface Component
    
    value - the value. If null, the attribute is removed.
    
    scope - one of Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE or Component.APPLICATION_SCOPE,
  - setAttribute
```
public java.lang.Object setAttribute(java.lang.String name,
                                     java.lang.Object value)
```
    Description copied from interface: Component
    
    Sets the custom attribute associated with this component, i.e., Component.COMPONENT_SCOPE.
    
    Specified by:
    
    setAttribute in interface Component
    
    Specified by:
    
    setAttribute in interface Scope
    
    Returns:
    
    the previous value associated with the attribute, if any
  - setAttribute
```
public java.lang.Object setAttribute(java.lang.String name,
                                     java.lang.Object value,
                                     boolean recurse)
```
    Description copied from interface: Scope
    
    Sets the custom attribute associated with this scope, or the parent scope.
    
    Specified by:
    
    setAttribute in interface Scope
    
    recurse - whether to look up the parent scope for the existence of the attribute.
    If recurse is true and the attribute is defined in one of its ancestor (including page), the attribute is replaced. Otherwise, it is the same as Scope.setAttribute(String,Object).
  - removeAttribute
```
public java.lang.Object removeAttribute(java.lang.String name,
                                        int scope)
```
    Description copied from interface: Component
    
    Removes the specified custom attribute in the specified scope.
    If scope is Component.COMPONENT_SCOPE, it means attributes private to this component.
    If scope is Component.SPACE_SCOPE, it means custom attributes shared by components from the same ID space as this one's.
    If scope is Component.PAGE_SCOPE, it means custom attributes shared by components from the same page as this one's.
    If scope is Component.DESKTOP_SCOPE, it means custom attributes shared by components from the same desktop as this one's.
    
    Specified by:
    
    removeAttribute in interface Component
    
    scope - Component.COMPONENT_SCOPE, Component.SPACE_SCOPE, Component.PAGE_SCOPE, Component.DESKTOP_SCOPE, Component.SESSION_SCOPE, Component.REQUEST_SCOPE or Component.APPLICATION_SCOPE,
  - removeAttribute
```
public java.lang.Object removeAttribute(java.lang.String name)
```
    Description copied from interface: Component
    
    Removes the custom attribute associated with this component, i.e., Component.COMPONENT_SCOPE.
    
    Specified by:
    
    removeAttribute in interface Component
    
    Specified by:
    
    removeAttribute in interface Scope
    
    Returns:
    
    the previous value associated with the attribute, if any,
  - removeAttribute
```
public java.lang.Object removeAttribute(java.lang.String name,
                                        boolean recurse)
```
    Description copied from interface: Scope
    
    Removes the custom attribute associated with this scope.
    
    Specified by:
    
    removeAttribute in interface Scope
    
    recurse - whether to look up the parent scope for the existence of the attribute.
    If recurse is true and the attribute is defined in one of its ancestor (including page), the attribute is removed. Otherwise, it is the same as Scope.removeAttribute(String).
  - getAttributeOrFellow
```
public java.lang.Object getAttributeOrFellow(java.lang.String name,
                                             boolean recurse)
```
    Description copied from interface: Component
    
    Returns the custom attribute associated with this component, or the fellow of this component; or null if not found.
    Notice that it doesn't check any variable defined in VariableResolver (of Page.addVariableResolver(org.zkoss.xel.VariableResolver)).
    
    Specified by:
    
    getAttributeOrFellow in interface Component
    
    recurse - whether to look up the parent component for the existence of the attribute.
    Notice that, if recurse is false and this component is not an ID space owner, it won't look at the fellow.
    If recurse is true, it will look up all parents, page, desktop, session and application until found. If any of them is a space owner, the fellows will be searched.
  - getShadowVariable
```
public java.lang.Object getShadowVariable(java.lang.String name,
                                          boolean recurse)
```
    Description copied from interface: Component
    
    Returns the shadow variable associated with this component or its parent component; or null if not found.
    Notice that it doesn't check any variable defined in VariableResolver (of Page.addVariableResolver(org.zkoss.xel.VariableResolver)).
    
    Specified by:
    
    getShadowVariable in interface Component
    
    recurse - whether to look up the parent component for the existence of the shadow variable.
    If recurse is true, it will look up all parents until found. If any of them is a shadow host.
  - getShadowVariable
```
public java.lang.Object getShadowVariable(Component baseChild,
                                          java.lang.String name,
                                          boolean recurse)
```
    Description copied from interface: Component
    
    Returns the shadow variable enclosed with the base component, which associated with this component or its parent component; or null if not found.
    Notice that it doesn't check any variable defined in VariableResolver (of Page.addVariableResolver(org.zkoss.xel.VariableResolver)).
    
    Specified by:
    
    getShadowVariable in interface Component
    
    Parameters:
    
    baseChild - the base component to seek the variable.
    
    recurse - whether to look up the parent component for the existence of the shadow variable.
    If recurse is true, it will look up all parents until found. If any of them is a shadow host.
    
    See Also:
    
    Component.getShadowVariable(String, boolean)
  - getShadowVariable0
```
protected java.lang.Object getShadowVariable0(Component baseChild,
                                              java.lang.String name,
                                              boolean recurse)
```
  - hasAttributeOrFellow
```
public boolean hasAttributeOrFellow(java.lang.String name,
                                    boolean recurse)
```
    Description copied from interface: Component
    
    Returns if a custom attribute is associated with this component, or the fellow of this component.
    Notice that it doesn't check any variable defined in VariableResolver (of Page.addVariableResolver(org.zkoss.xel.VariableResolver)).
    
    Specified by:
    
    hasAttributeOrFellow in interface Component
    
    recurse - whether to look up the parent component for the existence of the attribute.
    Notice that, if recurse is false and this component is not an ID space owner, it won't look at the fellow.
    If recurse is true, it will look up all parents, page, desktop, session and application until found. If any of them is a space owner, the fellows will be searched.
  - addScopeListener
```
public boolean addScopeListener(ScopeListener listener)
```
    Description copied from interface: Scope
    
    Adds a listener to listen whether this scope is changed. The listener is called when a custom attribute is added, removed, or the parent is changed.
    
    Specified by:
    
    addScopeListener in interface Scope
    
    Returns:
    
    weather the listener is added successfully. Note: if the resolver was added before, it won't be added again and this method returns false.
  - removeScopeListener
```
public boolean removeScopeListener(ScopeListener listener)
```
    Description copied from interface: Scope
    
    Removes a change listener from this scope.
    
    Specified by:
    
    removeScopeListener in interface Scope
    
    Returns:
    
    false if listener is not added before.
  - getAutag
```
public java.lang.String getAutag()
```
    Description copied from interface: Component
    
    Returns the AU tag for this widget. The AU tag tag is used to tag the AU requests sent by the peer widget. For instance, if the AU tag is xxx,yyy and the desktop's request path (Desktop.getRequestPath()) is /foo.zul, then the URL of the AU request will contain /_/foo.zul/xxx,yyy,.
    Default: null (no AU tag for this widget).
    
    Specified by:
    
    getAutag in interface Component
    
    See Also:
    
    Component.setAutag(java.lang.String)
  - setAutag
```
public void setAutag(java.lang.String tag)
```
    Description copied from interface: Component
    
    Sets the AU tag for this widget. The AU tag tag is used to tag the AU requests sent by the peer widget.
    
    Specified by:
    
    setAutag in interface Component
    
    Parameters:
    
    tag - the AU tag. Both an empty string and null are considered as null, i.e., no AU tag for this widget.
    
    See Also:
    
    Component.getAutag()
  - getParent
```
public Component getParent()
```
    Description copied from interface: Component
    
    Returns the parent component, or null if this is the root component.
    
    Specified by:
    
    getParent in interface Component
  - setParent
```
public void setParent(Component parent)
```
    Description copied from interface: Component
    
    Sets the parent component.
    Note: Component.setParent(org.zkoss.zk.ui.Component) always calls back Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and/or Component.removeChild(org.zkoss.zk.ui.Component), while Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.removeChild(org.zkoss.zk.ui.Component) always calls back Component.setParent(org.zkoss.zk.ui.Component), if the parent is changed. Thus, you don't need to override both Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.setParent(org.zkoss.zk.ui.Component), if you want to customize the behavior.
    
    Specified by:
    
    setParent in interface Component
  - insertBefore
```
public boolean insertBefore(Component newChild,
                            Component refChild)
```
    Description copied from interface: Component
    
    Inserts a child before the reference child.
    You could use Component.setParent(org.zkoss.zk.ui.Component) or Component.appendChild(org.zkoss.zk.ui.Component) instead of this method, unless you want to control where to put the child.
    Note: Component.setParent(org.zkoss.zk.ui.Component) always calls back Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and/or Component.removeChild(org.zkoss.zk.ui.Component), while Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.removeChild(org.zkoss.zk.ui.Component) always calls back Component.setParent(org.zkoss.zk.ui.Component), if the parent is changed. Thus, you don't need to override both Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.setParent(org.zkoss.zk.ui.Component), if you want to customize the behavior.
    If you would like to monitor if a component is attached or detached from a page, you could register a desktop listener implementing UiLifeCycle.
    
    Specified by:
    
    insertBefore in interface Component
    
    Parameters:
    
    newChild - the new child to be inserted.
    
    refChild - the child before which you want the new child being inserted. If null, the new child is append to the end.
    
    Returns:
    
    true if newChild is added successfully or moved; false if it already has the specified child and the order doesn't change.
  - replace
```
protected void replace(Component comp,
                       boolean bFellow,
                       boolean bListener,
                       boolean bChildren)
```
    Replace the specified component with this component in the component tree. In other words, the parent of the given component will become the parent of this components, so are siblings and children. Furthermore, comp will be detached at the end.
    Notice that the replacement won't change anything at the client. It is the caller'job to maintain the consistency between the server and the client.
    This method is rarely used.
    
    Parameters:
    
    comp - the component. In this implementation it supports only derived classes of AbstractComponent.
    
    bFellow - whether to add this component to the map of fellows if it is assigned with an ID. If false, the component (comp) cannot be retrieved back even with an ID (note: ID is always preserved).
    
    bListener - whether to retain the event listeners and handlers. If true, the event listeners and handlers, if any, will be registered to this stub component. In other words, the event will be processed. However, it is a stub component, rather than the original one. I means the event is the most generic format: an instance of Event (rather than MouseEvent or others).
    
    bChildren - whether to have the children of the given component.
    If false, this component won't have any children, and all UUID of children reference back to this component.
    If true, the given component's children will belong to this component.
    
    Throws:
    
    java.lang.IllegalStateException - if this component has a parent, sibling or child.
    
    Since:
    
    6.0.0
  - appendChild
```
public boolean appendChild(Component child)
```
    Appends a child to the end of all children. It calls insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) with refChild to be null. Derives cannot override this method, and they shall override insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) instead.
    
    Specified by:
    
    appendChild in interface Component
    
    See Also:
    
    Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component)
  - removeChild
```
public boolean removeChild(Component child)
```
    Description copied from interface: Component
    
    Removes a child. The child is not actually removed. Rather, it is detached (see Component.detach()) and it will be removed if it is no longer used.
    You could use Component.setParent(org.zkoss.zk.ui.Component) with null instead of this method.
    Note: Component.setParent(org.zkoss.zk.ui.Component) always calls back Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and/or Component.removeChild(org.zkoss.zk.ui.Component), while Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.removeChild(org.zkoss.zk.ui.Component) always calls back Component.setParent(org.zkoss.zk.ui.Component), if the parent is changed. Thus, you don't need to override both Component.insertBefore(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) and Component.setParent(org.zkoss.zk.ui.Component), if you want to customize the behavior.
    If you would like to monitor if a component is attached or detached from a page, you could register a desktop listener implementing UiLifeCycle.
    
    Specified by:
    
    removeChild in interface Component
    
    Returns:
    
    true if child is removed successfully; false if it doesn't have the specified child
  - isChildable
```
protected boolean isChildable()
```
    Returns whether this component can have a child.
    Default: return true (means it can have children).
  - getChildren
```
public <T extends Component> java.util.List<T> getChildren()
```
    Returns a live list of children. By live we mean the developer could add or remove a child by manipulating the returned list directly.
    Default: instantiates and returns an instance of AbstractComponent.Children.
    
    Specified by:
    
    getChildren in interface Component
  - getRoot
```
public Component getRoot()
```
    Returns the root of the specified component.
    
    Specified by:
    
    getRoot in interface Component
  - isVisible
```
public boolean isVisible()
```
    Description copied from interface: Component
    
    Returns whether this component is visible.
    
    Specified by:
    
    isVisible in interface Component
    
    See Also:
    
    Components.isRealVisible(org.zkoss.zk.ui.Component), Component.setVisible(boolean)
  - setVisible
```
public boolean setVisible(boolean visible)
```
    Description copied from interface: Component
    
    Sets whether this component is visible. A component is visible by default. Both visible and invisible components are rendered in a browser's DOM. But an invisible component's DOM elements with CSS display:none. Since a DOM element will inherit its parent's CSS rules, a component is visible only if all of its parents are also visible.
    To remove a component's DOM elements, use Component.detach().
    
    Specified by:
    
    setVisible in interface Component
    
    Returns:
    
    the previous visibility
  - setVisibleDirectly
```
protected void setVisibleDirectly(boolean visible)
```
    Changes the visibility directly without sending any update to the client. It is the caller's responsibility to maintain the consistency. It is rarely called. In most cases, you shall use setVisible(boolean) instead.
    
    Since:
    
    5.0.4
  - getStubonly
```
public java.lang.String getStubonly()
```
    Description copied from interface: Component
    
    Returns whether this component is stub-only. By stub-only, we mean we don't need to maintain the states of the component at the server side.
    There are three possible values: "true", "false", and "inherit", and "ignore-native".
    Notice that the native components will be stub-ized, no matter this property is set. Though rarely required, you could control whether to stub-ize the native components with a component attribute called Attributes.STUB_NATIVE.
    
    Specified by:
    
    getStubonly in interface Component
  - setStubonly
```
public void setStubonly(java.lang.String stubonly)
```
    Description copied from interface: Component
    
    Sets whether this component is stub-only. By stub-only, we mean we don't need to maintain the states of the component at the server side.
    Default: "inherit" (i.e., the same as the parent's stub-only, and "false" is assumed if none of parents is specified with stub-only).
    If a component is set to stub-only, the application running at the server shall not access it anymore after rendered to the client. The ZK loader will try to minimize the memory footprint by merging stub-only components and replacing with light-weight components.
    However, the event listeners and handlers are preserved, so they will be invoked if the corresponding event is received. Since the original component is gone, the event is the more generic format: an instance of Event (rather than MouseEvent or others).
    If a component is stub-only, the application usually access it only at the client since all widgets are preserved at the client (so are events).
    This method is available only for ZK EE.
    
    Specified by:
    
    setStubonly in interface Component
    
    Parameters:
    
    stubonly - whether it is stub-only. The allowed values include "true", "false" and "inherit".
  - setStubonly
```
public void setStubonly(boolean stubonly)
```
    Description copied from interface: Component
    
    Sets whether this component is stub-only. It is the same as setStubonly(stubonly ? "true": "false").
    
    Specified by:
    
    setStubonly in interface Component
  - isInvalidated
```
public boolean isInvalidated()
```
    Description copied from interface: Component
    Returns if this component needs to be redrawn at the client.
    Application developers rarely need to call this method.
    Note:
    1. It always returns true if it doesn't belong to any page (since redraw is required if it is attached to a page later).
    2. It always returns true if the current execution is not an asynchronous update (so redrawn is always required).
    3. If its parent is invalidated, this component will be redrawn too, but this method returns false if Component.invalidate() was not called against this component.
    Specified by:
    
    isInvalidated in interface Component
  - invalidate
```
public void invalidate()
```
    Description copied from interface: Component
    
    Invalidates this component by setting the dirty flag such that it will be redraw the whole content of this component and its dependencies later. And, the widget associated with this component and all its descendant at the client will be deleted and recreated, too.
    If the application is totally controlled by the server side (i.e., you don't write client codes), you rarely need to access this method.
    It can be called only in the request-processing and event-processing phases. However, it is NOT allowed in the rendering phase.
    
    Specified by:
    
    invalidate in interface Component
  - invalidatePartial
```
public void invalidatePartial()
```
    Description copied from interface: ComponentCtrl
    
    Invalidates this component by setting the dirty flag such that it will be redraw the partial content of this component and its dependencies later. And, the widget associated with this component and all its descendant at the client will be deleted and recreated, too.
    If the application is totally controlled by the server side (i.e., you don't write client codes), you rarely need to access this method.
    It can be called only in the request-processing and event-processing phases. However, it is NOT allowed in the rendering phase.
    
    Specified by:
    
    invalidatePartial in interface ComponentCtrl
  - response
```
protected void response(AuResponse response)
```
    Causes a response to be sent to the client. It is the same as response(response.getOverrideKey(), response)
    If AuResponse.getDepends() is not null, the response depends on the existence of the component returned by AuResponse.getDepends(). In other words, the response is removed if the component is removed. If it is null, the response is component-independent and it is always sent to the client.
    Unlike smartUpdate(java.lang.String, java.lang.Object), responses are sent even if Component.invalidate() was called. Typical examples include setting the focus, selecting the text and so on.
    It can be called only in the request-processing and event-processing phases; excluding the redrawing phase.
    
    Since:
    
    5.0.2
    
    See Also:
    
    response(String, AuResponse)
  - response
```
protected void response(java.lang.String key,
                        AuResponse response)
```
    Causes a response to be sent to the client by overriding the key returned by AuResponse.getOverrideKey()).
    If AuResponse.getDepends() is not null, the response depends on the existence of the component returned by AuResponse.getDepends(). In other words, the response is removed if the component is removed. If it is null, the response is component-independent and it is always sent to the client.
    Unlike smartUpdate(java.lang.String, java.lang.Object), responses are sent even if Component.invalidate() was called. Typical examples include setting the focus, selecting the text and so on.
    It can be called only in the request-processing and event-processing phases; excluding the redrawing phase.
    
    Parameters:
    
    key - could be anything. The second invocation of this method in the same execution with the same key and the same depends (AuResponse.getDepends()) will override the previous one. However, if key is null, it won't override any other. All responses with key == null will be sent.
    Notice that if AuResponse.getDepends() is null, then be careful of the key you used since it is shared in the same execution (rather than a particular component).
    
    Since:
    
    5.0.0 (become protected)
  - response
```
protected void response(java.lang.String key,
                        AuResponse response,
                        int priority)
```
    Causes a response to be sent to the client by overriding the key returned by AuResponse.getOverrideKey()).
    If AuResponse.getDepends() is not null, the response depends on the existence of the component returned by AuResponse.getDepends(). In other words, the response is removed if the component is removed. If it is null, the response is component-independent and it is always sent to the client.
    Unlike smartUpdate(java.lang.String, java.lang.Object), responses are sent even if Component.invalidate() was called. Typical examples include setting the focus, selecting the text and so on.
    It can be called only in the request-processing and event-processing phases; excluding the redrawing phase.
    
    Parameters:
    
    key - could be anything. The second invocation of this method in the same execution with the same key and the same depends (AuResponse.getDepends()) will override the previous one. However, if key is null, it won't override any other. All responses with key == null will be sent.
    Notice that if AuResponse.getDepends() is null, then be careful of the key you used since it is shared in the same execution (rather than a particular component).
    
    priority - The higher priority, the earlier the update is executed. The priority of response(AuResponse) and response(String, AuResponse) is assumed to be 0.
    If the priority is the same, the update is executed in the order of first-in-first out.
    
    Since:
    
    6.0.1
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           java.lang.Object value)
```
    Smart-updates a property of the peer widget associated with the component, running at the client, with the given value.
    The second invocation with the same property will replace the previous call. In other words, the same property will be set only once in each execution. If you prefer to send both updates to the client, use smartUpdate(String, Object, boolean) instead.
    This method has no effect if invalidate() is ever invoked (in the same execution), since invalidate() assumes the whole content shall be redrawn and all smart updates to this components can be ignored,
    Once invalidate() is called, all invocations to smartUpdate(String, Object) will then be ignored, and redraw(java.io.Writer) will be invoked later.
    It can be called only in the request-processing and event-processing phases; excluding the redrawing phase.
    There are two ways to draw a component, one is to invoke Component.invalidate(), and the other is smartUpdate(String, Object). While Component.invalidate() causes the whole content to redraw, smartUpdate(String, Object) let component developer control which part to redraw.
    
    Parameters:
    
    value - the new value. If it is DeferredValue, the value will be retrieved (by calling DeferredValue.getValue()) in the rendering phase. It is useful if the value can not be determined now.
    For some old application servers (example, Websphere 5.1), Execution.encodeURL(java.lang.String) cannot be called in the event processing thread. So, the developers have to use DeferredValue or disable the use of the event processing thread (by use of disable-event-thread in zk.xml).
    If you want to generate the JavaScript code directly (i.e., the value is a valid JavaScript snippet), you can use JavaScriptValue. Notice that the JavaScript code will be evaluated before assigning it to the widget.
    If the value is a Date object, a special pattern will be generated (a.k.a., marshaling) to ensure it can be unmarshalled back correctly at the client. Notice that it is marshalled to a string based on TimeZones.getCurrent(), and then unmarshalled back at the client. In other words, if the client is in different time-zone, the value returned by getTime() might be different. However, the value will remain the same if the client marshalled the Date object back. In other words, it assumes the browser's time zone from enduser's perspective (not really browser's setting) shall be the same as TimeZones.getCurrent().
    If the value is a component, a special pattern will be generated to ensure it can be unmarshalled back correctly at the client.
    In addition, the value can be any kind of objects that the client accepts (marshaled by JSON) (see also JSONAware).
    
    Since:
    
    5.0.0 (become protected)
    
    See Also:
    
    updateByClient(java.lang.String, java.lang.Object), smartUpdate(String, Object, boolean)
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           java.lang.Object value,
                           boolean append)
```
    Smart-updates a property of the peer widget with the given value that allows caller to decide whether to append or overwrite. In other words, smartUpdate(String, Object) is a shortcut of smartUpdate(attr, value, false).
    For example, if you invoke smartUpdate("attr", "value1") and smartUpdate("attr", "value2"), then only value2 will be sent to the client.
    However, if you invoke smartUpdate("attr", "value1", true) and smartUpdate("attr", "value2", true), then both value1 and value2 will be sent to the client. In other words, wgt.setAttr("value1") and wgt.setAttr("value2") will be invoked at the client accordingly.
    
    Parameters:
    
    append - whether to append the updates of properties with the same name. If false, only the last value of the same property will be sent to the client.
    
    Since:
    
    5.0.0
    
    See Also:
    
    smartUpdate(String, Object)
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           int value)
```
    A special smart update to update a value in int.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           long value)
```
    A special smart update to update a value in long.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           byte value)
```
    A special smart update to update a value in byte.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           char value)
```
    A special smart update to update a value in character.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           boolean value)
```
    A special smart update to update a value in boolean.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           float value)
```
    A special smart update to update a value in float.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdate
```
protected void smartUpdate(java.lang.String attr,
                           double value)
```
    A special smart update to update a value in double.
    It is the same as smartUpdate(String, Object).
    
    Since:
    
    5.0.0
  - smartUpdateWidgetListener
```
protected void smartUpdateWidgetListener(java.lang.String evtnm,
                                         java.lang.String script)
```
    A special smart update to update an event listener for the peer widget. By default, it assumes the peer widget has a method called setListener and it will be invoked as follows. wgt.setListener([evtnm, script]); Devices that supports it in another way have to override this method. Devices that don't support it have to override this method to throw UnsupportedOperationException.
    Parameters: evtnm - the event name, such as onClick script - the script. If null, it means to remove the event listener from the peer widget Since: 5.0.0
  smartUpdateWidgetOverride protected void smartUpdateWidgetOverride(java.lang.String name, java.lang.String script) A special smart update to update a method or a field of the peer widget. By default, it invokes the client widget's setOverride as follows. wgt.setOverride([name: script]); Devices that supports it in another way have to override this method. Devices that don't support it have to override this method to throw UnsupportedOperationException. Parameters: name - the method name, such as setValue script - the content of the method or field to override. Notice that it must be a valid JavaScript snippet. If null, the previous method/field override will be removed. And, the method/field defined in original widget will be restored. Since: 5.0.0 detach public void detach() Description copied from interface: Component Detaches this component such that it won't belong to any page. If you don't call Component.setParent(org.zkoss.zk.ui.Component) or Component.setPage(org.zkoss.zk.ui.Page) to attach it to any page, it will be removed automatically (from the client) after the current event is processed. Specified by: detach in interface Component beforeChildAdded public void beforeChildAdded(Component child, Component insertBefore) Default: does nothing. Specified by: beforeChildAdded in interface ComponentCtrl Parameters: child - the child to be added (never null). insertBefore - another child component that the new child will be inserted before it. If null, the new child will be the last child. Since: 3.6.2 See Also: ComponentCtrl.beforeChildAdded(org.zkoss.zk.ui.Component, org.zkoss.zk.ui.Component) beforeChildRemoved public void beforeChildRemoved(Component child) Default: does nothing. Specified by: beforeChildRemoved in interface ComponentCtrl Parameters: child - the child to be removed (never null) Since: 3.6.2 See Also: ComponentCtrl.beforeChildRemoved(org.zkoss.zk.ui.Component) beforeParentChanged public void beforeParentChanged(Component parent) Default: If parent is null, execute the @Destroy method if any. Specified by: beforeParentChanged in interface ComponentCtrl Parameters: parent - the new parent. If null, it means detachment. Since: 3.6.2 See Also: ComponentCtrl.beforeParentChanged(org.zkoss.zk.ui.Component) onChildAdded public void onChildAdded(Component child) Default: handles special event listeners. Specified by: onChildAdded in interface ComponentCtrl See Also: ComponentCtrl.onChildAdded(org.zkoss.zk.ui.Component) onChildRemoved public void onChildRemoved(Component child) Default: handles special event listeners. Specified by: onChildRemoved in interface ComponentCtrl See Also: ComponentCtrl.onChildRemoved(org.zkoss.zk.ui.Component) onPageAttached public void onPageAttached(Page newpage, Page oldpage) Default: handles special event listeners. Specified by: onPageAttached in interface ComponentCtrl Parameters: newpage - the new page (never null). oldpage - the previous page, if any, or null if it didn't belong to any page. Since: 3.0.0 See Also: ComponentCtrl.onPageAttached(org.zkoss.zk.ui.Page, org.zkoss.zk.ui.Page) onPageDetached public void onPageDetached(Page page) Default: handles special event listeners. Specified by: onPageDetached in interface ComponentCtrl Parameters: page - the previous page (never null) Since: 3.0.0 See Also: ComponentCtrl.onPageDetached(org.zkoss.zk.ui.Page) getWidgetClass public java.lang.String getWidgetClass() Returns the widget class (a.k.a., widget type), or null if not defined. Default: return the widget class based on the current mold (by use of ComponentDefinition.getWidgetClass(org.zkoss.zk.ui.Component, java.lang.String)), or null if not found. To override in Java, you could invoke setWidgetClass(java.lang.String). To override in ZUML, you could use the client namespace as follows. <window xmlns:w="http://www.zkoss.org/2005/zk/client" w:use="foo.MyWindow"> </window> Specified by: getWidgetClass in interface Component Since: 5.0.0 See Also: Component.setWidgetClass(java.lang.String) setWidgetClass public void setWidgetClass(java.lang.String wgtcls) Description copied from interface: Component Sets the widget class (a.k.a., the widget type). The widget class is a JavaScript class, including the package name. For example, "zul.wnd.Window". Specified by: setWidgetClass in interface Component Parameters: wgtcls - the widget's class name at the client side. If null (or empty), the default one is used (see Component.getWidgetClass()). getMold public java.lang.String getMold() Description copied from interface: Component Returns the mold used to render this component. Default: "default" Since 5.0, the default can be overridden by specify a library property. For example, if the component's class name is org.zkoss.zul.Button, then you can override the default mold by specifying the property called "org.zkoss.zul.Button.mold" with the mold you want in zk.xml. For example, <library-property> <name>org.zkoss.zul.Button.mold</name> <value>trendy</value> </library-property> Notice that it doesn't affect the deriving classes. If you want to change the deriving class's default mold, you have to specify them explicitly, too. Specified by: getMold in interface Component See Also: ComponentDefinition setMold public void setMold(java.lang.String mold) Description copied from interface: Component Sets the mold to render this component. Specified by: setMold in interface Component Parameters: mold - the mold. If null or empty, "default" is assumed. See Also: ComponentDefinition getSpecialRendererOutput protected java.lang.String getSpecialRendererOutput(Component comp) throws java.io.IOException Throws: java.io.IOException disableClientUpdate public boolean disableClientUpdate(boolean disable) Description copied from interface: ComponentCtrl Sets whether to disable the update of the client widgets of this component and its descendants. By default, if a component is attached to a page, modifications that change the visual representation will be sent to the client to ensure the consistency. Though rarely needed, you can disable the synchronization of the visual representation, if you prefer to update the client in a batch or the modification is caused by the client. Notice: Once disabled, it not only affects the synchronization of this component but also all its descendants. The disable remains until the end of this execution (or the invocation of this method with false). In other words, it is enabled automatically in the next execution. The updates, if any, before calling this method will still be sent to the client. It does nothing, if there is no current execution. Also notice that, with Component.invalidate(), it is easy to synchronize the content of a component (and its descendants) to the client. Specified by: disableClientUpdate in interface ComponentCtrl Returns: whether it has been disabled before this invocation, i.e., the previous disable status addRedrawCallback public boolean addRedrawCallback(Callback<ContentRenderer> callback) Description copied from interface: ComponentCtrl Adds a callback at component redraw phase. Specified by: addRedrawCallback in interface ComponentCtrl removeRedrawCallback public boolean removeRedrawCallback(Callback<ContentRenderer> callback) Description copied from interface: ComponentCtrl Removes a callback for component redraw phase. Specified by: removeRedrawCallback in interface ComponentCtrl getRedrawCallback public java.util.Collection<Callback<ContentRenderer>> getRedrawCallback() Description copied from interface: ComponentCtrl Returns all of callbacks for component redraw phase Specified by: getRedrawCallback in interface ComponentCtrl addCallback public boolean addCallback(java.lang.String name, Callback callback) Description copied from interface: ComponentCtrl Adds a callback at component in specific name Specified by: addCallback in interface ComponentCtrl removeCallback public boolean removeCallback(java.lang.String name, Callback callback) Description copied from interface: ComponentCtrl Removes a callback for component by specific name. Specified by: removeCallback in interface ComponentCtrl getCallback public java.util.Collection<Callback> getCallback(java.lang.String name) Description copied from interface: ComponentCtrl Returns all of callbacks by specific name Specified by: getCallback in interface ComponentCtrl redraw public void redraw(java.io.Writer out) throws java.io.IOException Redraws this component and all its descendants. Default: It uses JsContentRenderer to render all information in JavaScript codes. For devices that don't support JavaScript, it must override this method. To generate all information, it first invokes renderProperties(org.zkoss.zk.ui.sys.ContentRenderer) to render component's properties, and then redrawChildren(java.io.Writer) to redraw children (and descendants) (by calling their redraw(java.io.Writer)). If a derived class wants to render more properties, it can override renderProperties(org.zkoss.zk.ui.sys.ContentRenderer). If a derived class renders only a subset of its children (such as paging/cropping), it could override redrawChildren(java.io.Writer). If a deriving class wants to do something before renderProperties(org.zkoss.zk.ui.sys.ContentRenderer), it has to override redraw(java.io.Writer). If a deriving class doesn't want to render in JavaScript codes, it has to override redraw(java.io.Writer) with the proper implementation of ContentRenderer. Specified by: redraw in interface ComponentCtrl Throws: java.io.IOException redrawChildren protected void redrawChildren(java.io.Writer out) throws java.io.IOException Redraws children (and then recursively descendants). Default: it invokes redraw(java.io.Writer) for all its children. If a derived class renders only a subset of its children (such as paging/cropping), it could override redrawChildren(java.io.Writer). Throws: java.io.IOException Since: 5.0.0 See Also: redraw(java.io.Writer) renderProperties protected void renderProperties(ContentRenderer renderer) throws java.io.IOException Called by (ComponentCtrl.redraw(java.io.Writer)) to render the properties, excluding the enclosing tag and children. Default: it renders getId() if it was assigned, and event names if listened (and listed in getClientEvents()). Note: it doesn't render getWidgetClass(), getUuid() and getMold(), which are caller's job. Throws: java.io.IOException Since: 5.0.0 render protected void render(ContentRenderer renderer, java.lang.String name, java.lang.String value) throws java.io.IOException An utility to be called by renderProperties(org.zkoss.zk.ui.sys.ContentRenderer) to render a string-value property. It ignores if value is null or empty. If you want to render it even if null/empty, invoke ContentRenderer.render(String, String) directly. Throws: java.io.IOException Since: 5.0.0 render protected void render(ContentRenderer renderer, java.lang.String name, java.lang.Object value) throws java.io.IOException An utility to be called by renderProperties(org.zkoss.zk.ui.sys.ContentRenderer) to render a string-value property. It ignores if value is null. If you want to render it even if null, invoke ContentRenderer.render(String, Object) directly. Throws: java.io.IOException Since: 5.0.0 render protected void render(ContentRenderer renderer, java.lang.String name, boolean value) throws java.io.IOException An utility to be called by renderProperties(org.zkoss.zk.ui.sys.ContentRenderer) to render a boolean-value property if it is true. If you want to render it no matter true or false, use ContentRenderer.render(String, boolean) directly. Throws: java.io.IOException Since: 5.0.0 getClientEvents public java.util.Map<java.lang.String,java.lang.Integer> getClientEvents() Returns a map of event information that the client might send to this component. The key of the returned map is a String instance representing the event name, and the value an integer representing the flags (a combination of ComponentCtrl.CE_IMPORTANT, ComponentCtrl.CE_NON_DEFERRABLE, ComponentCtrl.CE_BUSY_IGNORE, ComponentCtrl.CE_DUPLICATE_IGNORE and ComponentCtrl.CE_REPEAT_IGNORE). Default: return the collection of events added by getClientEvents(). Rather than overriding this method, it is suggested to invoke addClientEvent(java.lang.Class<? extends org.zkoss.zk.ui.Component>, java.lang.String, int) in the static statement. For example, public MyComponent extend HtmlBasedComponent { static { addClientEvent(MyComponent.class, "onOpen", 0); } Specified by: getClientEvents in interface ComponentCtrl Since: 5.0.0 addClientEvent protected static void addClientEvent(java.lang.Class<? extends Component> cls, java.lang.String evtnm, int flags) Adds an event that the client might send to the server. addClientEvent(java.lang.Class<? extends org.zkoss.zk.ui.Component>, java.lang.String, int) is usually called in the static clause when the class is loaded. For example, public class MyWidget extends HtmlBasedComponent { static { addClientEvent(MyWidget.class, "onFly", 0); } ... For a programming language not easy to have the static clause (such as Scala), addClientEvent(java.lang.Class<? extends org.zkoss.zk.ui.Component>, java.lang.String, int) can be called in the constructors. Notice that it is better not to add the client event later than the constructor, since the derived classes will copy the client events defined in the base class, when the first time addClientEvent(java.lang.Class<? extends org.zkoss.zk.ui.Component>, java.lang.String, int) is called with the class. Version History Since 5.0.4, it can be called in constructors (in additions to the static clause). On other hand, it can only be called in the static clause (executed when the class is loaded) in the prior version. Parameters: cls - the component's class (implementation class). flags - a combination of ComponentCtrl.CE_IMPORTANT, ComponentCtrl.CE_NON_DEFERRABLE ComponentCtrl.CE_BUSY_IGNORE, ComponentCtrl.CE_DUPLICATE_IGNORE and ComponentCtrl.CE_REPEAT_IGNORE. Since: 5.0.0 addEventListener public boolean addEventListener(java.lang.String evtnm, EventListener<? extends Event> listener) Description copied from interface: Component Adds an event listener to specified event name for this component. The second registration is ignored and false is returned. The priority is assumed to 0. You could register listener to all components in the same page by use of Page.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>). Version Difference ZK 5.0 and earlier, the second registration is ignored if an event listener has been registered twice. However, since 6.0.0 and later, it won't be ignored. If a listener has been registered multiple times, it will be invoked multiple times. If you prefer to ignore the second registration, you could specify a library property called "org.zkoss.zk.ui.EventListener.duplicateIgnored" to true. Specified by: addEventListener in interface Component Parameters: evtnm - what event to listen (never null) Returns: whether the listener is added successfully See Also: Page.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>) addEventListener public boolean addEventListener(int priority, java.lang.String evtnm, EventListener<? extends Event> listener) Description copied from interface: Component Adds an event listener to specified event name for this component with the given priority. You could register listener to all components in the same page by use of Page.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>). Version Difference ZK 5.0 and earlier, the second registration is ignored if an event listener has been registered twice. However, since 6.0.0 and later, it won't be ignored. If a listener has been registered multiple times, it will be invoked multiple times. If you prefer to ignore the second registration, you could specify a library property called "org.zkoss.zk.ui.EventListener.duplicateIgnored" to true. Specified by: addEventListener in interface Component Parameters: priority - the priority of the event. The higher the priority is, the earlier it is invoked. Notice: If the priority equals or is greater than 1000, the event listener will be invoked before the event handlers registered in a ZUML page (i.e., the onXxx attribute declared in ZUML). On the other hand, if the priority is lower than 1000, it is invoked after the ZUML's event handler. The priority registered by Component.addEventListener(String, EventListener) is 0. Applications shall not use the priority higher than 10,000 and lower than -10,000 since they are reserved for component development. evtnm - what event to listen (never null) Returns: whether the listener is added successfully See Also: Page.addEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>) removeEventListener public boolean removeEventListener(java.lang.String evtnm, EventListener<? extends Event> listener) Description copied from interface: Component Removes an event listener. Specified by: removeEventListener in interface Component Returns: whether the listener is removed; false if it was never added. addForward public boolean addForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent) Description copied from interface: Component Adds a forward condition to forward the event received by this component to another component. Default: no forward condition at all. Once the condition is added, a event called targetEvent is posted to the target component, when this component receives the orginalEvent event. Specified by: addForward in interface Component Parameters: orgEvent - the original event that was received by this component. If null, "onClick" is assumed. target - the target component to receive the event. If null, the space owner Component.getSpaceOwner() is assumed. If null and the space owner is the page, the root component is assumed. targetEvent - the target event that the target component will receive. If null, it is the same as the original event. Returns: whether it is added successfully. It returns false if the condition was always added before. See Also: Component.removeForward(String, Component, String), Component.addForward(String, Component, String, Object) addForward public boolean addForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent) Description copied from interface: Component Adds a forward condition to forward the event received by this component to another component, specified with a path. Note: the target component is retrieved from the path, each time the event is received. Thus, you can reference to a component that is created later. Specified by: addForward in interface Component Parameters: orgEvent - the original event that was received by this component. If null, "onClick" is assumed. targetPath - the target component's path related to this component. If ".", this component is assumed. If null, the space owner is assumed. If null and the space owner is the page, the root component is assumed. targetEvent - the target event that the target component will receive. If null, it is the same as the original event. Returns: whether it is added successfully. It returns false if the condition was always added before. See Also: Component.addForward(String, Component, String), Component.removeForward(String, String, String) addForward public boolean addForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent, java.lang.Object eventData) Description copied from interface: Component Adds a forward condition to forward the event received by this component to another component with extra event data. Specified by: addForward in interface Component eventData - the extra data that can be retrieve by Event.getData(). See Also: Component.addForward(String, Component, String) addForward public boolean addForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent, java.lang.Object eventData) Description copied from interface: Component Adds a forward condition to forward the event received by this component to another component of the specified path with extra event data. Specified by: addForward in interface Component eventData - the extra data that can be retrieve by Event.getData(). See Also: Component.addForward(String, String, String) removeForward public boolean removeForward(java.lang.String orgEvent, Component target, java.lang.String targetEvent) Description copied from interface: Component Removes a forward condition that was added by Component.addForward(String, Component, String). If no such forward condition exists, nothing happens but return false. Specified by: removeForward in interface Component Parameters: orgEvent - the original event that was received by this component. It must be the same as the one passed to Component.addForward(String, Component, String). target - the target component to receive the event. It must be the same as the one passed to Component.addForward(String, Component, String). targetEvent - the target event that the target component will receive. It must be the same as the one passed to Component.addForward(String, Component, String). Returns: whether the forward is removed successfully. It returns false if the forward condition is not found See Also: Component.addForward(String, Component, String) removeForward public boolean removeForward(java.lang.String orgEvent, java.lang.String targetPath, java.lang.String targetEvent) Description copied from interface: Component Removes a forward condition that was added by Component.addForward(String, String, String). If no such forward condition exists, nothing happens but return false. Specified by: removeForward in interface Component Parameters: orgEvent - the original event that was received by this component. It must be the same as the one passed to Component.addForward(String, Component, String). targetPath - the target component's path related to this component. If ".", this component is assumed. If null, the space owner is assumed. If null and the space owner is the page, the root component is assumed. targetEvent - the target event that the target component will receive. It must be the same as the one passed to Component.addForward(String, Component, String). Returns: whether the forward is removed successfully. It returns false if the forward condition is not found See Also: Component.addForward(String, String, String) isListenerAvailable public boolean isListenerAvailable(java.lang.String evtnm, boolean asap) Description copied from interface: Component Returns whether the event listener is available. Unlike Events.isListened(org.zkoss.zk.ui.Component, java.lang.String, boolean), this method checks only the event listener registered by Component.addEventListener(int, java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>). Specified by: isListenerAvailable in interface Component asap - whether to check only non-deferrable listener, i.e., not implementing Deferrable, or Deferrable.isDeferrable() is false. See Also: Deferrable, Events.isListened(org.zkoss.zk.ui.Component, java.lang.String, boolean), Component.addEventListener(int, java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>) getListenerIterator public java.util.Iterator<EventListener<? extends Event>> getListenerIterator(java.lang.String evtnm) Deprecated. As of release 6.0, replaced with getEventListeners(java.lang.String). Specified by: getListenerIterator in interface Component getEventListeners public java.lang.Iterable<EventListener<? extends Event>> getEventListeners(java.lang.String evtnm) Description copied from interface: Component Returns an iterable collection of the event listeners for the given event. Note: it is OK to invoke Component.addEventListener(int, java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>) or Component.removeEventListener(java.lang.String, org.zkoss.zk.ui.event.EventListener<? extends org.zkoss.zk.ui.event.Event>) when iterating through the event listeners with the returned collection. To remove an event listener from the returned iterable collection, you could invoke Iterable.iterator()'s Iterator.remove(). Specified by: getEventListeners in interface Component applyProperties public void applyProperties() Description copied from interface: Component Initializes the properties (a.k.a. members) based on what are defined in the component definition. This method is invoked automatically if a component is created by evaluating a ZUML page, i.e., if it is specified as an element of a ZUML page. On the other hand, if it is created manually (by program), developer might choose to invoke this method or not, depending whether he wants to initializes the component with the properties defined in the ZUML page (PageDefinition) and the language definition (LanguageDefinition). Notice that, since 5.0.7, custom-attributes are applied automatically in the constructor of AbstractComponent, so they are always available no matter this method is called or not. Specified by: applyProperties in interface Component getDefinition public ComponentDefinition getDefinition() Description copied from interface: Component Returns the component definition of this component (never null). Specified by: getDefinition in interface Component setDefinition public void setDefinition(ComponentDefinition compdef) Description copied from interface: ComponentCtrl Sets the component definition. The component definition affects how a component behaves. Developers rarely need to call this method. If a wrong definition is assigned, the result is unpredictable (and hard to debug). It is mainly designed for developing tools. Specified by: setDefinition in interface ComponentCtrl setDefinition public void setDefinition(java.lang.String name) Description copied from interface: ComponentCtrl Sets the component definition by specifying the name. Specified by: setDefinition in interface ComponentCtrl Parameters: name - the name of the component definition getEventHandler public ZScript getEventHandler(java.lang.String evtnm) Description copied from interface: ComponentCtrl Returns the event listener of the specified name, or null if not found. Specified by: getEventHandler in interface ComponentCtrl See Also: Component.getWidgetListener(java.lang.String) addSharedEventHandlerMap public void addSharedEventHandlerMap(EventHandlerMap evthds) Description copied from interface: ComponentCtrl Adds a map of event handlers which is shared by other components. In other words, this component shall have all event handlers defined in the specified map, evthds. Meanwhile, this component shall not modify evthds, since it is shared. The caller shall not change annots after the invocation, too Specified by: addSharedEventHandlerMap in interface ComponentCtrl Parameters: evthds - a map of event handler See Also: Component.setWidgetListener(java.lang.String, java.lang.String) getEventHandlerNames public java.util.Set<java.lang.String> getEventHandlerNames() Description copied from interface: ComponentCtrl Returns a readonly collection of event names (String), or an empty collection if no event name is registered. Specified by: getEventHandlerNames in interface ComponentCtrl See Also: Component.getWidgetListenerNames() addEventHandler public void addEventHandler(java.lang.String name, EventHandler evthd) Description copied from interface: ComponentCtrl Adds an event handler. Note: it is OK to add multiple event handlers to the same event. They are evaluated one-by-one. On the other hand, Component.setWidgetListener(java.lang.String, java.lang.String) will overwrite the previous listener if the event name is the same. Specified by: addEventHandler in interface ComponentCtrl See Also: Component.setWidgetListener(java.lang.String, java.lang.String) getAnnotation public Annotation getAnnotation(java.lang.String annotName) Deprecated. As of release 6.0.0, replaced with getAnnotation(String, String). Specified by: getAnnotation in interface ComponentCtrl getAnnotation public Annotation getAnnotation(java.lang.String propName, java.lang.String annotName) Description copied from interface: ComponentCtrl Returns the annotation associated with the definition of the specified property, or null if not available. If there are multiple annotation with the given name, this method will merge them before return. If you prefer to get all of them without merging, please use ComponentCtrl.getAnnotations(String, String) instead. For example, <textbox value="@bind(abc, param1=foo1) @bind(xyz, param2=foo2)"> This method will return a single annotation with three attributes: value=xyz, param1=foo1 and param2=foo2. On the other hand, ComponentCtrl.getAnnotations(String, String) will return a two-element collections. Notice that the property is not limited the 'real' property. For example, the following statement is correct though button doesn't have setFoo method. And, you can retrieve it by use of this method (getAnnotation("foo", "bind")) <button foo="@bind(whatever=123)"/> Furthermore, you can declare it as custom-attribute. For example, the following is equivalent to the above. <button> <custom-attribute foo="@bind(whatever=123}"> </button> Specified by: getAnnotation in interface ComponentCtrl Parameters: propName - the property name, e.g., "value". If null, this method returns the annotation(s) associated with this component (rather than a particular property). annotName - the annotation name See Also: ComponentCtrl.getAnnotations(String, String) getAnnotations public java.util.Collection<Annotation> getAnnotations(java.lang.String propName, java.lang.String annotName) Description copied from interface: ComponentCtrl Returns the annotations associated with the definition of the specified property. It never returns null. Notice that the property is not limited the 'real' property. For example, the following statement is correct though button doesn't have setFoo method. And, you can retrieve it by use of this method (getAnnotation("foo", "bind")) <button foo="@bind(whatever=123)"/> Furthermore, you can declare it as custom-attribute. For example, the following is equivalent to the above. <button> <custom-attribute foo="@bind(whatever=123}"> </button> Specified by: getAnnotations in interface ComponentCtrl Parameters: propName - the property name, e.g., "value". If null, this method returns the annotation(s) associated with this component (rather than a particular property). annotName - the annotation name See Also: ComponentCtrl.getAnnotation(String, String) getAnnotations public java.util.Collection<Annotation> getAnnotations() Deprecated. As of release 6.0.0, replaced with getAnnotations(String). Specified by: getAnnotations in interface ComponentCtrl getAnnotations public java.util.Collection<Annotation> getAnnotations(java.lang.String propName) Description copied from interface: ComponentCtrl Returns a read-only collection of all annotations (Annotation) associated with the specified property. It never returns null. Specified by: getAnnotations in interface ComponentCtrl Parameters: propName - the property name, e.g., "value". If null, this method returns the annotation(s) associated with this component (rather than a particular property). getAnnotatedPropertiesBy public java.util.List<java.lang.String> getAnnotatedPropertiesBy(java.lang.String annotName) Description copied from interface: ComponentCtrl Returns a read-only list of the names of the properties that are associated with the specified annotation (never null). Specified by: getAnnotatedPropertiesBy in interface ComponentCtrl getAnnotatedProperties public java.util.List<java.lang.String> getAnnotatedProperties() Description copied from interface: ComponentCtrl Returns a read-only list of the name of properties that are associated at least one annotation (never null). Specified by: getAnnotatedProperties in interface ComponentCtrl addAnnotation public void addAnnotation(java.lang.String annotName, java.util.Map<java.lang.String,java.lang.String[]> annotAttrs) Deprecated. As of release 6.0.0, replaced with addAnnotation(String, String, Map) Specified by: addAnnotation in interface ComponentCtrl addAnnotation public void addAnnotation(java.lang.String propName, java.lang.String annotName, java.util.Map<java.lang.String,java.lang.String[]> annotAttrs) Description copied from interface: ComponentCtrl Adds an annotation to the specified property of this component. If the given property is null, the annotation is associated to this component, rather than a particular property. Unlike Java, you can add annotations dynamically, and each component has its own annotations. Specified by: addAnnotation in interface ComponentCtrl Parameters: propName - the property name. If null, the annotation is associated with the component (rather than a particular property). annotName - the annotation name (never null, nor empty). annotAttrs - a map of attributes, or null if no attribute at all. This method will make a copy of annotAttrs, so the caller can use it after the invocation. sessionWillPassivate public void sessionWillPassivate(Page page) Description copied from interface: ComponentCtrl Notification that the session, which owns this component, is about to be passivated (a.k.a., serialized). Note: only root components are notified by this method. Specified by: sessionWillPassivate in interface ComponentCtrl sessionDidActivate public void sessionDidActivate(Page page) Description copied from interface: ComponentCtrl Notification that the session, which owns this component, has just been activated (a.k.a., deserialized). Note: only root components are notified by this method. Specified by: sessionDidActivate in interface ComponentCtrl willPassivate protected void willPassivate(java.util.Collection<?> c) Utility to invoke ComponentActivationListener.willPassivate(org.zkoss.zk.ui.Component) for each object in the collection. Parameters: c - a collection of objects. Ignored if null. Since: 3.6.4 willPassivate protected void willPassivate(java.lang.Object o) Utility to invoke ComponentActivationListener.willPassivate(org.zkoss.zk.ui.Component) for the specified object. Parameters: o - the object to invoke. Ignore if ComponentActivationListener not implemented or null. Since: 3.6.4 didActivate protected void didActivate(java.util.Collection<?> c) Utility to invoke ComponentActivationListener.didActivate(org.zkoss.zk.ui.Component) for each object in the collection. Parameters: c - a collection of objects. Ignored if null. Since: 3.6.4 didActivate protected void didActivate(java.lang.Object o) Utility to invoke ComponentActivationListener.didActivate(org.zkoss.zk.ui.Component) for the specified object. Parameters: o - the object to invoke. Ignore if ComponentActivationListener not implemented or null. Since: 3.6.4 getExtraCtrl public java.lang.Object getExtraCtrl() Returns the extra controls that tell ZK how to handle this component specially. It is used only by component developers. Default: null. Specified by: getExtraCtrl in interface ComponentCtrl Returns: null if no special handling required. If the component requires some special controls, it could return an object that implements one or several interfaces in the org.zkoss.zk.ui.ext.render package. For example, Cropper. See Also: ComponentCtrl.getExtraCtrl() getPropertyAccess public PropertyAccess getPropertyAccess(java.lang.String prop) Description copied from interface: ComponentCtrl Returns the corresponding property access object from the given property name, if any. Specified by: getPropertyAccess in interface ComponentCtrl Parameters: prop - the name of the property Returns: null it means not to support for the property name. onWrongValue public WrongValueException onWrongValue(WrongValueException ex) Notifies that an WrongValueException instance is thrown, and WrongValueException.getComponent() is this component. It is a callback and the component can store the error message, show up the custom information, or even 'eat' the exception. Default: does nothing but returns ex. Specified by: onWrongValue in interface ComponentCtrl Parameters: ex - the exception being thrown (never null) Returns: the exception to throw, or null to ignore the exception In most cases, just return ex Since: 2.4.0 getAuService public AuService getAuService() Description copied from interface: Component Returns an AU service to process the AU request before the component's default handling. Default: null Specified by: getAuService in interface Component setAuService public void setAuService(AuService ausvc) Description copied from interface: Component Sets an AU service to process the AU request before the component's default handling. This method is used if you want to send some custom request from client (by your application). Default: null. If you want to provide an AU service for the AU requests targeting the desktop. Use Desktop.addListener(java.lang.Object). See also How to process AU requests with JSON. Specified by: setAuService in interface Component service public void service(AuRequest request, boolean everError) Handles an AU request. It is invoked internally. Default: it handles echo and setAttr, and it converts other request to an event (by Event.getEvent(org.zkoss.zk.au.AuRequest)) and then posts the event (by Events.postEvent(org.zkoss.zk.ui.event.Event)). Application developer can plug the custom service to handle the AU request by setAuService(org.zkoss.zk.au.AuService). Specified by: service in interface ComponentCtrl everError - whether any error ever occurred before processing this request. Since: 5.0.0 See Also: setAuService(org.zkoss.zk.au.AuService) service public void service(Event event, Scope scope) throws java.lang.Exception Description copied from interface: ComponentCtrl Handles an event. This method will invoke the event handlers registered in a ZUML page, the event listeners registered in Java, and the event handlers declared as part of the component. Specified by: service in interface ComponentCtrl Parameters: event - the event to handle scope - the scope to evaluate the zscript, if any. (see also Page.interpret(java.lang.String, java.lang.String, org.zkoss.zk.ui.ext.Scope). Throws: java.lang.Exception getEventListenerMap public EventListenerMap getEventListenerMap() Description copied from interface: ComponentCtrl Returns the map of event handlers and listeners defined in this component. This method is rarely used, but it is useful if you'd like to retrieve the behavior of the event handling of this component (and if you don't have the reference to the component) Specified by: getEventListenerMap in interface ComponentCtrl updateByClient protected void updateByClient(java.lang.String name, java.lang.Object value) Called when the widget running at the client asks the server to update a value. The update is caused by an AU request named setAttr (by invoking zk.Widget's smartUpdate at client). By default, it does nothing but log a warning message, since it is not safe to allow the client to update a field arbitrary. However, if you'd like to allow the update for a particular component you could do one of the following For component developers: override this method to update the field directly. For example, protected void updateByClient(String name, Object value) { if ("disabled".equals(name)) setDisabled(name, ((Boolean)value).booleanValue()); else super.updateByClient(name, value); For application developers: set an attribute called org.zkoss.zk.ui.updateByClient to be true. Then, this method will use reflection to find out the setter to update the value. Nothing happens if the method is not found. Notice: this method will invoke disableClientUpdate(boolean) to disable any update to the client, when calling the setter. If you want to enable the client update for all instances of a given component (though not recommended for the security reason), you could refer to here. See also zk.Widget.smartUpdate(). Since: 5.0.0 toString public java.lang.String toString() Overrides: toString in class java.lang.Object clone public java.lang.Object clone() Description copied from interface: Component Clones the component. All of its children and descendants are cloned. Also, ID are preserved. Specified by: clone in interface Component Overrides: clone in class java.lang.Object Returns: the new component. Notice that it doesn't belong to any page, nor desktop. It doesn't have a parent, either. willSerialize protected void willSerialize(java.util.Collection c) Utility to invoke ComponentSerializationListener.willSerialize(org.zkoss.zk.ui.Component) for each object in the collection. Parameters: c - a collection of objects. Ignored if null. Since: 3.6.4 willSerialize protected void willSerialize(java.lang.Object o) Utility to invoke ComponentSerializationListener.willSerialize(org.zkoss.zk.ui.Component) for the specified object. Parameters: o - the object to invoke. Ignore if ComponentSerializationListener not implemented or null. Since: 3.6.4 didDeserialize protected void didDeserialize(java.util.Collection c) Utility to invoke ComponentSerializationListener.didDeserialize(org.zkoss.zk.ui.Component) for each object in the collection. Parameters: c - a collection of objects. Ignored if null. Since: 3.6.4 didDeserialize protected void didDeserialize(java.lang.Object o) Utility to invoke ComponentSerializationListener.didDeserialize(org.zkoss.zk.ui.Component) for the specified object. Parameters: o - the object to invoke. Ignore if ComponentSerializationListener not implemented or null. Since: 3.6.4 getDefaultMold protected java.lang.String getDefaultMold(java.lang.Class<? extends Component> klass) Returns the default mold for the given class. Default: check the library property called xxx.mold, where xxx is the name of the give class. If not found or empty, "default" is assumed. Subclass might override this method to use the default mold of the base class, such as protected String getDefaultMold(Class klass) { return super.getDefaultMold(Button.class); } Since: 5.0.3 getTemplate public Template getTemplate(java.lang.String name) Description copied from interface: Component Returns the template of the given name, or null if not available. Specified by: getTemplate in interface Component See Also: Component.setTemplate(java.lang.String, org.zkoss.zk.ui.util.Template) setTemplate public Template setTemplate(java.lang.String name, Template template) Description copied from interface: Component Sets a UI template which could be retrieved later with Component.getTemplate(java.lang.String). Specified by: setTemplate in interface Component Parameters: name - the template's name. It cannot be empty or null. template - the template to assign. If it is null, the previous template, if any, will be removed Returns: the previous template, if any getTemplateNames public java.util.Set<java.lang.String> getTemplateNames() Description copied from interface: Component Returns a readonly set of the names of all templates. Specified by: getTemplateNames in interface Component query public Component query(java.lang.String selector) Description copied from interface: Component Find the first component that matches the given CSS3 selector. Specified by: query in interface Component Parameters: selector - the CSS3 selector. For example, comp.query("#id div"). Returns: the first matched component, or null if not found See Also: Component.queryAll(java.lang.String) queryAll public java.lang.Iterable<Component> queryAll(java.lang.String selector) Description copied from interface: Component Returns an iterable object for components that match the given CSS3 selector. Notice: this method traverses the whole component tree, only if you iterate through the whole iterable object. In other words, the performance is good, and you can iterate it find the object that matches your criteria. Specified by: queryAll in interface Component Parameters: selector - the CSS3 selector. For example, comp.queryAll("#id div"). Returns: a list of all matched component, or an empty list if none is found. See Also: Component.query(java.lang.String) getShadowRoots public <T extends ShadowElement> java.util.List<T> getShadowRoots() Description copied from interface: ComponentCtrl Returns a set of shadow elements, if any. Specified by: getShadowRoots in interface ComponentCtrl removeShadowRoot public boolean removeShadowRoot(ShadowElement shadow) Description copied from interface: ComponentCtrl Removes the given shadow root from this host. (Shadow developer use only) Specified by: removeShadowRoot in interface ComponentCtrl Parameters: shadow - a shadow element Returns: true if child is removed successfully; false if it doesn't have the specified child addShadowRoot public boolean addShadowRoot(ShadowElement shadow) Description copied from interface: ComponentCtrl Adds the given shadow root from this host. (Shadow developer use only) Specified by: addShadowRoot in interface ComponentCtrl Parameters: shadow - a shadow element Returns: true if child is added successfully addShadowRootBefore public boolean addShadowRootBefore(ShadowElement shadow, ShadowElement insertBefore) Description copied from interface: ComponentCtrl Adds the given shadow root from this host. (Shadow developer use only) Specified by: addShadowRootBefore in interface ComponentCtrl Parameters: shadow - a shadow element insertBefore - the shadow before which you want the new child Returns: true if child is added successfully hasBindingAnnotation public boolean hasBindingAnnotation() Description copied from interface: ComponentCtrl Returns whether the component itself has binding annotation or not. (Internal or component developer use only.) Specified by: hasBindingAnnotation in interface ComponentCtrl Returns: true if the component itself has binding annotation hasSubBindingAnnotation public boolean hasSubBindingAnnotation() Description copied from interface: ComponentCtrl Returns whether the component and its children have binding annotation or not. (Internal or component developer use only.) Specified by: hasSubBindingAnnotation in interface ComponentCtrl Returns: true if the component and its children have binding annotation getSubBindingAnnotationCount public int getSubBindingAnnotationCount() Description copied from interface: ComponentCtrl Returns the count of the component's subtree binding annotation. (Internal or component developer use only.) Specified by: getSubBindingAnnotationCount in interface ComponentCtrl Returns: 0 if the component and its children have no binding annotation , more than 0 if they have binding annotation updateSubBindingAnnotationCount protected void updateSubBindingAnnotationCount(int diff) setSubBindingAnnotationCount protected void setSubBindingAnnotationCount(int diff, AbstractComponent node) enableBindingAnnotation public void enableBindingAnnotation() Description copied from interface: ComponentCtrl Set to enable the component with binding annotation. (Internal or component developer use only.) Specified by: enableBindingAnnotation in interface ComponentCtrl disableBindingAnnotation public void disableBindingAnnotation() Description copied from interface: ComponentCtrl Set to disable the component with binding annotation. (Internal or component developer use only.) Specified by: disableBindingAnnotation in interface ComponentCtrl getShadowFellowIfAny public ShadowElement getShadowFellowIfAny(java.lang.String id) Description copied from interface: ComponentCtrl Returns the shadow element under this shadow host. Specified by: getShadowFellowIfAny in interface ComponentCtrl Returns: ShadowElement or null isInitialized public boolean isInitialized() Returns if it's finished layout phase (initializing). Returns: true if it's initialized. Since: 9.5.1

Class AbstractComponent

Nested Class Summary

Field Summary

Fields inherited from interface org.zkoss.zk.ui.Component

Fields inherited from interface org.zkoss.zk.ui.sys.ComponentCtrl

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.zkoss.zk.ui.sys.ComponentCtrl

Constructor Detail

AbstractComponent

AbstractComponent

Method Detail

getPage

getDesktop

setPage

setPageBefore

addMoved

getId

setId

getUuid

getSpaceOwner

hasFellow

hasFellow

getFellow

getFellow

getFellowIfAny

getFellowIfAny

getFellows

getNextSibling

getPreviousSibling

getFirstChild

getLastChild

setWidgetListener

getWidgetListener

getWidgetListenerNames

setWidgetOverride

getWidgetOverride

getWidgetOverrideNames

setWidgetAttribute

setClientAttribute

getWidgetAttribute

getClientAttribute

getWidgetAttributeNames

setClientDataAttribute

getClientDataAttribute

getAttributes

getAttributes

getAttribute

getAttribute

getAttribute

hasAttribute

hasAttribute

hasAttribute

setAttribute

setAttribute

setAttribute

removeAttribute

removeAttribute

removeAttribute

getAttributeOrFellow

getShadowVariable

getShadowVariable

getShadowVariable0

hasAttributeOrFellow

addScopeListener

removeScopeListener

getAutag

setAutag

getParent

setParent

insertBefore

replace

appendChild

removeChild

isChildable

getChildren

getRoot

isVisible

setVisible