public class

DelegatingKeyboardListenerCollection

extends KeyboardListenerCollection
implements KeyboardListener
java.lang.Object
   ↳ java.util.AbstractCollection<E>
     ↳ java.util.AbstractList<E>
       ↳ java.util.ArrayList<E>
         ↳ com.google.gwt.user.client.ui.KeyboardListenerCollection
           ↳ com.google.gwt.user.client.ui.DelegatingKeyboardListenerCollection

This class is deprecated.
Use delegateEvent(Widget, GwtEvent) instead

Class Overview

KeyboardListenerCollection used to correctly hook up event listeners to the composite's wrapped widget.

For example, Composite widgets often need to listen to events generated on their wrapped widget. Upon the firing of a wrapped widget's event, the composite widget must fire its own listeners with itself as the source of the event. To use a DelegatingKeyboardListenerCollection, simply use the DelegatingKeyboardListenerCollection instead of a KeyboardListenerCollection. For example, in SuggestBox, the following code is used to listen to keyboard events on the SuggestBox underlying widget.

  public void addKeyboardListener(KeyboardListener listener) {
    if (keyboardListeners == null) {
      keyboardListeners = new DelegatingKeyboardListenerCollection(this, box);
    }
    keyboardListeners.add(listener);
  }

Summary

[Expand]
Inherited Constants
From interface com.google.gwt.user.client.ui.KeyboardListener
[Expand]
Inherited Fields
From class java.util.AbstractList
Public Constructors
DelegatingKeyboardListenerCollection(Widget owner, SourcesKeyboardEvents delegatedTo)
Public Methods
void onKeyDown(Widget sender, char keyCode, int modifiers)
Fired when the user depresses a physical key.
void onKeyPress(Widget sender, char keyCode, int modifiers)
Fired when a keyboard action generates a character.
void onKeyUp(Widget sender, char keyCode, int modifiers)
Fired when the user releases a physical key.
[Expand]
Inherited Methods
From class com.google.gwt.user.client.ui.KeyboardListenerCollection
From class java.util.ArrayList
From class java.util.AbstractList
From class java.util.AbstractCollection
From class java.lang.Object
From interface com.google.gwt.user.client.ui.KeyboardListener
From interface java.lang.Iterable
From interface java.util.Collection
From interface java.util.List

Public Constructors

public DelegatingKeyboardListenerCollection (Widget owner, SourcesKeyboardEvents delegatedTo)

Parameters
owner owner of listeners
delegatedTo source of events

Public Methods

public void onKeyDown (Widget sender, char keyCode, int modifiers)

Fired when the user depresses a physical key.

Parameters
sender the widget that was focused when the event occurred.
keyCode the physical key that was depressed. Constants for this value are defined in this interface with the KEY prefix.
modifiers the modifier keys pressed at when the event occurred. This value is a combination of the bits defined by MODIFIER_SHIFT, MODIFIER_CTRL, and MODIFIER_ALT

public void onKeyPress (Widget sender, char keyCode, int modifiers)

Fired when a keyboard action generates a character. This occurs after onKeyDown and onKeyUp are fired for the physical key that was pressed.

It should be noted that many browsers do not generate keypress events for non-printing keyCode values, such as KEY_ENTER or arrow keys. These keyCodes can be reliably captured either with onKeyDown(Widget, char, int) or onKeyUp(Widget, char, int).

Parameters
sender the widget that was focused when the event occurred.
keyCode the Unicode character that was generated by the keyboard action.
modifiers the modifier keys pressed at when the event occurred. This value is a combination of the bits defined by MODIFIER_SHIFT, MODIFIER_CTRL, and MODIFIER_ALT

public void onKeyUp (Widget sender, char keyCode, int modifiers)

Fired when the user releases a physical key.

Parameters
sender the widget that was focused when the event occurred.
keyCode the physical key that was released. Constants for this value are defined in this interface with the KEY prefix.
modifiers the modifier keys pressed at when the event occurred. This value is a combination of the bits defined by MODIFIER_SHIFT, MODIFIER_CTRL, and MODIFIER_ALT