Class DragSourceAdapter

public abstract class DragSourceAdapter
extends Object
implements DragSourceListener, DragSourceMotionListener

An abstract adapter class for receiving drag source events. The methods in this class are empty. This class exists only as a convenience for creating listener objects.

Extend this class to create a DragSourceEvent listener and override the methods for the events of interest. (If you implement the DragSourceListener interface, you have to define all of the methods in it. This abstract class defines null methods for them all, so you only have to define methods for events you care about.)

Create a listener object using the extended class and then register it with a DragSource. When the drag enters, moves over, or exits a drop site, when the drop action changes, and when the drag ends, the relevant method in the listener object is invoked, and the DragSourceEvent is passed to it.

The drop site is associated with the previous dragEnter() invocation if the latest invocation of dragEnter() on this adapter corresponds to that drop site and is not followed by a dragExit() invocation on this adapter.

Constructors

DragSourceAdapter

public DragSourceAdapter()

Methods

dragEnter

public void dragEnter(DragSourceDragEvent dsde)

Called as the cursor's hotspot enters a platform-dependent drop site. This method is invoked when all the following conditions are true:

• The cursor's hotspot enters the operable part of a platform-dependent drop site.
• The drop site is active.
• The drop site accepts the drag.

Specified by:

dragEnter in interface DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dragOver

public void dragOver(DragSourceDragEvent dsde)

Called as the cursor's hotspot moves over a platform-dependent drop site. This method is invoked when all the following conditions are true:

• The cursor's hotspot has moved, but still intersects the operable part of the drop site associated with the previous dragEnter() invocation.
• The drop site is still active.
• The drop site accepts the drag.

Specified by:

dragOver in interface DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dragMouseMoved

public void dragMouseMoved(DragSourceDragEvent dsde)

Called whenever the mouse is moved during a drag operation.

Specified by:

dragMouseMoved in interface DragSourceMotionListener

Parameters:

dsde - the DragSourceDragEvent

dropActionChanged

public void dropActionChanged(DragSourceDragEvent dsde)

Called when the user has modified the drop gesture. This method is invoked when the state of the input device(s) that the user is interacting with changes. Such devices are typically the mouse buttons or keyboard modifiers that the user is interacting with.

Specified by:

dropActionChanged in interface DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dragExit

public void dragExit(DragSourceEvent dse)

Called as the cursor's hotspot exits a platform-dependent drop site. This method is invoked when any of the following conditions are true:

• The cursor's hotspot no longer intersects the operable part of the drop site associated with the previous dragEnter() invocation.

OR

• The drop site associated with the previous dragEnter() invocation is no longer active.

OR

• The drop site associated with the previous dragEnter() invocation has rejected the drag.

Specified by:

dragExit in interface DragSourceListener

Parameters:

dse - the DragSourceEvent

dragDropEnd

public void dragDropEnd(DragSourceDropEvent dsde)

This method is invoked to signify that the Drag and Drop operation is complete. The getDropSuccess() method of the DragSourceDropEvent can be used to determine the termination state. The getDropAction() method returns the operation that the drop site selected to apply to the Drop operation. Once this method is complete, the current DragSourceContext and associated resources become invalid.

Specified by:

dragDropEnd in interface DragSourceListener

Parameters:

dsde - the DragSourceDropEvent