jpicedt.graphic.toolkit

Class AbstractMouseTransform

java.lang.Object

jpicedt.graphic.toolkit.AbstractMouseTransform

All Implemented Interfaces:

MouseTransform

Direct Known Subclasses:

EditElementMouseTransformFactory._MoveControlPointTransform, EditElementMouseTransformFactory._MoveElementTransform

public abstract class AbstractMouseTransform
extends java.lang.Object
implements MouseTransform

This implementation allows subclassers to modify a clone of the target Element, then to update the original Element when the operation is completed. The aim is to reduce the burden of repainting a (possibly) complex Element while transforming it, by painting the Element using very lightweight View. This is done as follow :

• first clone the given Element, and add it to a transient RootElement defined as an inner class ;
• then create a "lightweight" View for this Element using a dedicated ViewFactory defined as an inner class ;
• apply the transformation to the clone while the mouse is being dragged/moved/pressed ... Note that the implementation of MouseTransform.paint() arranges for properly painting the clone by asking its lightweight View.
• when the transformation has completed, update the original Element and delete the clone.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractMouseTransform(Element target)

Method Summary

Modifier and Type	Method and Description
protected Element	getClone() Return the clone of the target element, which was init'd by startTransform
protected Element	getTarget() Return the element this transform acts upon
boolean	next(PEMouseEvent e) Called by mouseReleased. This implementation set the clone's parent and view to null so as to make it elligible for gc.
void	paint(java.awt.Graphics2D g, java.awt.geom.Rectangle2D allocation, double scale) Paints the clone.
void	start(PEMouseEvent e) Called by mousePressed. Creates a clone of the target (e.g.

Methods inherited from class java.lang.Object

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

Methods inherited from interface jpicedt.graphic.toolkit.MouseTransform

getCursor, getHelpMessage, process

Constructor Detail

AbstractMouseTransform

protected AbstractMouseTransform(Element target)

Parameters:

target - The target-element upon which this transform will act.

Method Detail

start

public void start(PEMouseEvent e)

Called by mousePressed.
Creates a clone of the target (e.g. a clicked Element) given as a parameter to the constructor, and sets its View using a dedicated ViewFactory (defined as an inner class) so that only the stroke of the element will be painted (using a default basic stroke to reduce the burden of repainting).

Specified by:

start in interface MouseTransform

next

public boolean next(PEMouseEvent e)

Called by mouseReleased.
This implementation set the clone's parent and view to null so as to make it elligible for gc. This should be called by subclassers at the end of the implementation of their "next" method.

Specified by:

next in interface MouseTransform

Returns:

true if there's another task in the sequence, false if mouse-transform has completed with this mouse-event.

paint

public void paint(java.awt.Graphics2D g,
                  java.awt.geom.Rectangle2D allocation,
                  double scale)

Paints the clone. This is normally called by EditorKit upon request by the installed PECanvas.

Specified by:

paint in interface MouseTransform

getTarget

protected Element getTarget()

Return the element this transform acts upon

getClone

protected Element getClone()

Return the clone of the target element, which was init'd by startTransform