Package ca.cgjennings.ui.dnd

Class AbstractDragAndDropHandler<T>

java.lang.Object

ca.cgjennings.ui.dnd.AbstractDragAndDropHandler<T>

All Implemented Interfaces:

DragHandler<T>, DropHandler<T>

public abstract class AbstractDragAndDropHandler<T>
extends java.lang.Object
implements DragHandler<T>, DropHandler<T>

An abstract base class that combines a DragHandler and a DropHandler in a single object. This can be a useful basis for building interactions with reasonably simple drag logic, such as dragging and dropping between two containers. For convenience, the method acceptDrop returns true; the methods dragFinished, dragEnter, dragExit, and dragMove have empty implementations.

Since:

3.0

Author:

Chris Jennings

Constructor Summary

Constructors

Constructor	Description
AbstractDragAndDropHandler()

Method Summary

Modifier and Type	Method	Description
boolean	acceptDrop(DragManager<T> manager, javax.swing.JComponent dragSource, DragToken<T> token, javax.swing.JComponent dropTarget, java.awt.Point location)	Called to determine if a drop target is willing to accept a particular drop.
void	dragEnter(DragManager<T> manager, javax.swing.JComponent dragSource, DragToken<T> token, javax.swing.JComponent dropTarget, java.awt.Point location)	Called when the cursor enters a viable drop target.
void	dragExit(DragManager<T> manager, javax.swing.JComponent dragSource, DragToken<T> token, javax.swing.JComponent dropTarget)	Called when the cursor leaves a drop target (or moves over part of the target that will not accept the drop).
void	dragFinished(DragManager<T> manager, javax.swing.JComponent dragSource, DragToken<T> token, javax.swing.JComponent dropTarget)	Called when a drag gesture finishes, whether the drag token was successfully dropped or not.
void	dragMove(DragManager<T> manager, javax.swing.JComponent dragSource, DragToken<T> token, javax.swing.JComponent dropTarget, java.awt.Point location)	Called when the cursor is moved over a viable drop target.

Methods inherited from class java.lang.Object

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

Methods inherited from interface ca.cgjennings.ui.dnd.DragHandler

createDragToken

Methods inherited from interface ca.cgjennings.ui.dnd.DropHandler

handleDrop

Constructor Detail

AbstractDragAndDropHandler

public AbstractDragAndDropHandler()

Method Detail

acceptDrop

public boolean acceptDrop(DragManager<T> manager,
                          javax.swing.JComponent dragSource,
                          DragToken<T> token,
                          javax.swing.JComponent dropTarget,
                          java.awt.Point location)

Description copied from interface: DropHandler

Called to determine if a drop target is willing to accept a particular drop.

Specified by:

acceptDrop in interface DropHandler<T>

Parameters:

manager - the manager that is managing the drag

dragSource - the component being dragged from

token - the token that was dragged

dropTarget - the target that the token would be dropped on

location - the location of the potential drop

Returns:

true if the handler would allow the drop, false otherwise

dragFinished

public void dragFinished(DragManager<T> manager,
                         javax.swing.JComponent dragSource,
                         DragToken<T> token,
                         javax.swing.JComponent dropTarget)

Description copied from interface: DragHandler

Called when a drag gesture finishes, whether the drag token was successfully dropped or not. This method is called after

Specified by:

dragFinished in interface DragHandler<T>

Parameters:

manager - the manager that is managing the drag

dragSource - the component being dragged from

token - the token that was dragged

dropTarget - the target that the token was dropped on, or null if the drag was cancelled

dragEnter

public void dragEnter(DragManager<T> manager,
                      javax.swing.JComponent dragSource,
                      DragToken<T> token,
                      javax.swing.JComponent dropTarget,
                      java.awt.Point location)

Description copied from interface: DropHandler

Called when the cursor enters a viable drop target. This can be used to update the visual representation of the target.

Specified by:

dragEnter in interface DropHandler<T>

Parameters:

manager - the manager that is managing the drag

dragSource - the component being dragged from

token - the token that was dragged

dropTarget - the target that the token is being dropped on

location - the location of the cursor

dragExit

public void dragExit(DragManager<T> manager,
                     javax.swing.JComponent dragSource,
                     DragToken<T> token,
                     javax.swing.JComponent dropTarget)

Description copied from interface: DropHandler

Called when the cursor leaves a drop target (or moves over part of the target that will not accept the drop). This can be used to update the visual representation of the target.

Specified by:

dragExit in interface DropHandler<T>

Parameters:

manager - the manager that is managing the drag

dragSource - the component being dragged from

token - the token that was dragged

dropTarget - the target that the token is being dropped on

dragMove

public void dragMove(DragManager<T> manager,
                     javax.swing.JComponent dragSource,
                     DragToken<T> token,
                     javax.swing.JComponent dropTarget,
                     java.awt.Point location)

Description copied from interface: DropHandler

Called when the cursor is moved over a viable drop target. This can be used to update the visual representation of the target.

Specified by:

dragMove in interface DropHandler<T>

Parameters:

manager - the manager that is managing the drag

dragSource - the component being dragged from

token - the token that was dragged

dropTarget - the target that the token is being dropped on

location - the location of the cursor