diva.canvas.event

Class EventLayer

java.lang.Object

diva.canvas.CanvasLayer

diva.canvas.event.EventLayer

All Implemented Interfaces:

CanvasComponent, EventAcceptor

public class EventLayer
extends CanvasLayer
implements EventAcceptor

An event layer is a canvas layer that accepts mouse events. It is designed to be layered over or under other layers, such as FigureLayer, and accepts a number of options that control whether it consumes events and so on. Event layers can have event listeners attached to them, which will be notified when events occur.

Sample uses of the event layer

• On top of a figure layer, events consumed: trap all events before they get to the figure layer.
• On top of a figure layer, events not consumed: monitor all events but still allow the figure layer to respond.
• Behind of a figure layer: catch events on the "background" of the pane, which didn't hit a figure in the figure layer.

Version:

$Id: EventLayer.java 70398 2014-10-22 23:44:32Z cxh $

Author:

John Reekie

Constructor Summary

Constructors

Constructor and Description
EventLayer()

Method Summary

Modifier and Type	Method and Description
void	addInteractor(Interactor i) Add an interactor to this interactor.
void	addLayerListener(LayerListener l) Add the given layer listener to this dispatcher.
void	addLayerMotionListener(LayerMotionListener l) Add the given layer motion listener to this dispatcher.
void	dispatchEvent(java.awt.AWTEvent event) Dispatch an AWT event on this layer.
java.util.Iterator	interactors() Return an interactor over the attached interactors.
boolean	isConsuming() Test the consuming flag of this layer.
boolean	isEnabled() Test the enabled flag of this layer.
protected void	processLayerEvent(LayerEvent event) Process a layer event.
void	removeInteractor(Interactor i) Remove the given interactor from this interactor.
void	removeLayerListener(LayerListener l) Remove the given layer listener from this dispatcher.
void	removeLayerMotionListener(LayerMotionListener l) Remove the given layer motion listener from this dispatcher.
void	setConsuming(boolean flag) Set the consuming flag of this layer.
void	setEnabled(boolean flag) Set the enabled flag of this layer.

Methods inherited from class diva.canvas.CanvasLayer

getCanvasPane, getLayerBounds, getParent, getToolTipText, getTransformContext, repaint, repaint, setParent

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface diva.canvas.CanvasComponent

getParent, getTransformContext, repaint, repaint

Constructor Detail

EventLayer

public EventLayer()

Method Detail

addInteractor

public void addInteractor(Interactor i)

Add an interactor to this interactor. The added interactor will have events forwarded to it if it accepts the event.

addLayerListener

public void addLayerListener(LayerListener l)

Add the given layer listener to this dispatcher.

addLayerMotionListener

public void addLayerMotionListener(LayerMotionListener l)

Add the given layer motion listener to this dispatcher.

dispatchEvent

public void dispatchEvent(java.awt.AWTEvent event)

Dispatch an AWT event on this layer. Currently only layer events are handled.

Specified by:

dispatchEvent in interface EventAcceptor

interactors

public java.util.Iterator interactors()

Return an interactor over the attached interactors.

isConsuming

public boolean isConsuming()

Test the consuming flag of this layer. If this flag is set, the layer consumes all input events.

isEnabled

public boolean isEnabled()

Test the enabled flag of this layer. Note that this flag does not indicate whether the layer is actually enabled, as its pane or one if its ancestors may not be enabled.

Specified by:

isEnabled in interface EventAcceptor

processLayerEvent

protected void processLayerEvent(LayerEvent event)

Process a layer event. This method dispatches the event to any registered layer listeners or layer motion listeners, and then to any interactors. If the "consuming" flag is set, it consumes the event before returning.

removeInteractor

public void removeInteractor(Interactor i)

Remove the given interactor from this interactor.

removeLayerListener

public void removeLayerListener(LayerListener l)

Remove the given layer listener from this dispatcher.

removeLayerMotionListener

public void removeLayerMotionListener(LayerMotionListener l)

Remove the given layer motion listener from this dispatcher.

setConsuming

public void setConsuming(boolean flag)

Set the consuming flag of this layer. If this flag is set, the layer consumes all input events.

setEnabled

public void setEnabled(boolean flag)

Set the enabled flag of this layer. If the flag is false, then the layer will not respond to user input events.

Specified by:

setEnabled in interface EventAcceptor