Package org.eclipse.gef
Class KeyHandler
java.lang.Object
org.eclipse.gef.KeyHandler
- Direct Known Subclasses:
- GraphicalViewerKeyHandler
The KeyHandler should handle all normal keystrokes on an
 
EditPartViewer. Normal is simply defined as keystrokes
 which are not associated with an Accelerator on the Menu. The KeyHandler will
 be forwarded KeyEvents by the active Tool, which is usually the
 SelectionTool. The Tool may be in a state where keystrokes should not be
 processed, in which case it will not forward the keystrokes. For this reason,
 it is important to always handle KeyEvents by using a KeyHandler.
 
 KeyHandlers can be chained by calling setParent(KeyHandler). If this
 KeyHandler does not handle the keystroke, it will pass the keystroke to its
 parent KeyHandler.
 
 KeyHandlers can be implemented using two stragegies. One is to map
 KeyStrokes to Actions using the put(KeyStroke, IAction) and
 remove(KeyStroke) API. The other is to subclass KeyHandler, and
 override various methods. A combination of the two is also useful.
- Since:
- 2.0
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Constructor SummaryConstructors
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Method SummaryModifier and TypeMethodDescriptionbooleankeyPressed(KeyEvent event) Processes a key pressed event.booleankeyReleased(KeyEvent event) Processes a key released event.voidMaps a specifiedKeyStroketo anIAction.voidRemoved a mappedIActionfor the specifiedKeyStroke.setParent(KeyHandler parent) Sets a parentKeyHandlerto which this KeyHandler will forward un-consumed KeyEvents.
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Constructor Details- 
KeyHandlerpublic KeyHandler()
 
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Method Details- 
keyPressedProcesses a key pressed event. This method is called by the Tool whenever a key is pressed, and the Tool is in the proper state.- Parameters:
- event- the KeyEvent
- Returns:
- trueif KeyEvent was handled in some way
 
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keyReleasedProcesses a key released event. This method is called by the Tool whenever a key is released, and the Tool is in the proper state.- Parameters:
- event- the KeyEvent
- Returns:
- trueif KeyEvent was handled in some way
 
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putMaps a specifiedKeyStroketo anIAction. When a KeyEvent occurs matching the given KeyStroke, the Action will berun()iff it is enabled.- Parameters:
- keystroke- the KeyStroke
- action- the Action to run
 
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removeRemoved a mappedIActionfor the specifiedKeyStroke.- Parameters:
- keystroke- the KeyStroke to be unmapped
 
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setParentSets a parentKeyHandlerto which this KeyHandler will forward un-consumed KeyEvents. This KeyHandler will first attempt to handle KeyEvents. If it does not recognize a given KeyEvent, that event is passed to its parent- Parameters:
- parent- the parent KeyHandler
- Returns:
- thisfor convenience
 
 
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