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package java.awt.dnd;

import java.util.EventListener;


The DragSourceListener defines the
event interface for originators of
Drag and Drop operations to track the state of the user's gesture, and to
provide appropriate "drag over"
feedback to the user throughout the
Drag and Drop operation.


The drop site is associated with the previous dragEnter()
invocation if the latest invocation of dragEnter() on this
listener:

    

  • corresponds to that drop site and

  •  is not followed by a dragExit() invocation on this listener.



Since:1.2
/**
 * The <code>DragSourceListener</code> defines the
 * event interface for originators of
 * Drag and Drop operations to track the state of the user's gesture, and to
 * provide appropriate &quot;drag over&quot;
 * feedback to the user throughout the
 * Drag and Drop operation.
 * <p>
 * The drop site is <i>associated with the previous <code>dragEnter()</code>
 * invocation</i> if the latest invocation of <code>dragEnter()</code> on this
 * listener:
 * <ul>
 * <li>corresponds to that drop site and
 * <li> is not followed by a <code>dragExit()</code> invocation on this listener.
 * </ul>
 *
 * @since 1.2
 */

public interface DragSourceListener extends EventListener {

    
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.



Params:
  • dsde – the DragSourceDragEvent
/**
     * Called as the cursor's hotspot enters a platform-dependent drop site.
     * This method is invoked when all the following conditions are true:
     * <UL>
     * <LI>The cursor's hotspot enters the operable part of a platform-
     * dependent drop site.
     * <LI>The drop site is active.
     * <LI>The drop site accepts the drag.
     * </UL>
     *
     * @param dsde the <code>DragSourceDragEvent</code>
     */
    void dragEnter(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.



Params:
  • dsde – the DragSourceDragEvent
/**
     * Called as the cursor's hotspot moves over a platform-dependent drop site.
     * This method is invoked when all the following conditions are true:
     * <UL>
     * <LI>The cursor's hotspot has moved, but still intersects the
     * operable part of the drop site associated with the previous
     * dragEnter() invocation.
     * <LI>The drop site is still active.
     * <LI>The drop site accepts the drag.
     * </UL>
     *
     * @param dsde the <code>DragSourceDragEvent</code>
     */
    void dragOver(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.

Params:
  • dsde – the DragSourceDragEvent
/**
     * 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.
     *
     * @param dsde the <code>DragSourceDragEvent</code>
     */
    void dropActionChanged(DragSourceDragEvent dsde);

    
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.



Params:
  • dse – the DragSourceEvent
/**
     * Called as the cursor's hotspot exits a platform-dependent drop site.
     * This method is invoked when any of the following conditions are true:
     * <UL>
     * <LI>The cursor's hotspot no longer intersects the operable part
     * of the drop site associated with the previous dragEnter() invocation.
     * </UL>
     * OR
     * <UL>
     * <LI>The drop site associated with the previous dragEnter() invocation
     * is no longer active.
     * </UL>
     * OR
     * <UL>
     * <LI> The drop site associated with the previous dragEnter() invocation
     * has rejected the drag.
     * </UL>
     *
     * @param dse the <code>DragSourceEvent</code>
     */
    void dragExit(DragSourceEvent dse);

    
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.

Params:
  • dsde – the DragSourceDropEvent
/**
     * This method is invoked to signify that the Drag and Drop
     * operation is complete. The getDropSuccess() method of
     * the <code>DragSourceDropEvent</code> 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 <code>DragSourceContext</code> and
     * associated resources become invalid.
     *
     * @param dsde the <code>DragSourceDropEvent</code>
     */
    void dragDropEnd(DragSourceDropEvent dsde);
}