Package org.zkoss.zk.ui.event

## Interface Deferrable

-     public interface Deferrable

  Used to decorate `EventListener` to denote whether the event for the listener can be deferred.

  By default (without implementing `Deferrable`), the event is sent to the server immediately when it is triggered at the client.

  To make a listener deferrable, you have to implement `Deferrable` and return true for `isDeferrable()`. Then, the event won't be sent until another non-deferrable event is about to send to the server.

  The deferrable events are used to improve the performance by minimizing the traffic between the clients and the server. It is usually used for event listeners that maintains the application states, rather than generating visual responses.

  Author:
    tomyeh
  See Also:
    `EventListener`

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `boolean` | `isDeferrable()` | Returns whether the event can be deferred for this listener.

- - ### Method Detail

    - #### isDeferrable

          boolean isDeferrable()

      Returns whether the event can be deferred for this listener. If false is returned, it is the same as not implementing this interface at all.