Chapter 5: Handling User Input"
From Documentation
Line 193: | Line 193: | ||
= MVVM Approach = | = MVVM Approach = | ||
+ | <!-- | ||
+ | * brief intro MVVM pattern | ||
+ | * what data binding does | ||
+ | * create a ViewModel | ||
+ | * create a zul | ||
+ | * apply a ViewModel | ||
+ | * add a property binding | ||
+ | * command and notify change | ||
+ | --> | ||
== Introduction == | == Introduction == |
Revision as of 03:17, 17 January 2013
Target Application
This chapter we will demonstrate a common scenario: collecting user input in form-based page. The target application looks as follows:
There is a personal profile form with 5 different fields. Click the "Save" button saves users input and click the "Reload" button loads previous saved data back to the form. We will show how to implement these functions in both MVC and MVVM approach.
MVC Approach
View
<?link rel="stylesheet" type="text/css" href="/style.css"?>
<window apply="org.zkoss.tutorial.chapter5.mvc.ProfileViewController"
border="normal" hflex="1" vflex="1" contentStyle="overflow:auto">
<caption src="/imgs/profile.png" sclass="fn-caption" label="Profile (MVC)"/>
<vlayout>
<grid width="500px">
<columns>
<column align="right" hflex="min"/>
<column/>
</columns>
<rows>
<row>
<cell sclass="row-title">Account :</cell>
<cell><label id="account"/></cell>
</row>
<row>
<cell sclass="row-title">Full Name :</cell>
<cell><textbox id="fullName" constraint="no empty: Plean enter your full name" width="200px"/></cell>
</row>
<row>
<cell sclass="row-title">Email :</cell>
<cell><textbox id="email" constraint="/.+@.+\.[a-z]+/: Please enter an e-mail address" width="200px"/></cell>
</row>
<row>
<cell sclass="row-title">Birthday :</cell>
<cell><datebox id="birthday" constraint="no future" width="200px"/></cell>
</row>
<row>
<cell sclass="row-title">Country :</cell>
<cell>
<listbox id="country" mold="select" width="200px">
<template name="model">
<listitem label="${each}" />
</template>
</listbox>
</cell>
</row>
<row>
<cell sclass="row-title">Bio :</cell>
<cell><textbox id="bio" multiline="true" hflex="1" height="200px" /></cell>
</row>
</rows>
</grid>
<hlayout>
<button id="saveProfile" label="Save"/>
<button id="reloadProfile" label="Reload"/>
</hlayout>
</vlayout>
</window>
Display a Collection of Data
public class ProfileViewController extends SelectorComposer<Component>{
...
@Wire
Listbox country;
@Override
public void doAfterCompose(Component comp) throws Exception{
super.doAfterCompose(comp);
ListModelList<String> countryModel = new ListModelList<String>(CommonInfoService.getCountryList());
country.setModel(countryModel);
refreshProfileView();
}
...
}
Handle Events in a Composer
public class ProfileViewController extends SelectorComposer<Component>{
//wire components
@Wire
Label account;
@Wire
Textbox fullName;
@Wire
Textbox email;
@Wire
Datebox birthday;
@Wire
Listbox country;
@Wire
Textbox bio;
@Listen("onClick=#saveProfile")
public void doSaveProfile(){
UserCredential cre = authService.getUserCredential();
User user = userInfoService.findUser(cre.getAccount());
if(user==null){
//TODO handle un-authenticated access
return;
}
//apply component value to bean
user.setFullName(fullName.getValue());
user.setEmail(email.getValue());
user.setBirthday(birthday.getValue());
user.setBio(bio.getValue());
Set<String> selection = ((Selectable)country.getModel()).getSelection();
if(!selection.isEmpty()){
user.setCountry(selection.iterator().next());
}else{
user.setCountry(null);
}
userInfoService.updateUser(user);
Clients.showNotification("Your profile is updated");
}
...
}
public class ProfileViewController extends SelectorComposer<Component>{
//wire components
@Wire
Label account;
@Wire
Textbox fullName;
@Wire
Textbox email;
@Wire
Datebox birthday;
@Wire
Listbox country;
@Wire
Textbox bio;
...
@Listen("onClick=#reloadProfile")
public void doReloadProfile(){
refreshProfileView();
}
private void refreshProfileView() {
UserCredential cre = authService.getUserCredential();
User user = userInfoService.findUser(cre.getAccount());
if(user==null){
//TODO handle un-authenticated access
return;
}
//apply bean value to UI components
account.setValue(user.getAccount());
fullName.setValue(user.getFullName());
email.setValue(user.getEmail());
birthday.setValue(user.getBirthday());
bio.setValue(user.getBio());
((Selectable)country.getModel()).addToSelection(user.getCountry());
}
}