/*******************************************************************************
* Copyright (c) 2000, 2003 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.dnd;
import org.eclipse.swt.internal.SWTEventListener;
/**
* The <code>DragSourceListener</code> class provides event notification to the application for DragSource events.
*
* <p>When the user drops data on a <code>DropTarget</code>, the application which defines the <code>DragSource</code>
* must provide the dropped data by implementing <code>dragSetData</code>. In the dragSetData, the application
* must support all the data types that were specified in the DragSource#setTransfer method.</p>
*
* <p>After the drop has completed successfully or has been aborted, the application which defines the
* <code>DragSource</code> is required to take the appropriate cleanup action. In the case of a successful
* <b>move</b> operation, the application must remove the data that was transferred.</p>
* @since 1.3
*/
public interface DragSourceListener extends SWTEventListener {
/**
* The user has begun the actions required to drag the widget. This event gives the application
* the chance to decide if a drag should be started.
*
* <p>The following fields in the DragSourceEvent apply:
* <ul>
* <li>(in)widget
* <li>(in)time
* <li>(in,out)doit
* </ul></p>
*
* @param event the information associated with the drag start event
*
* @see DragSourceEvent
*/
public void dragStart(DragSourceEvent event);
/**
* The data is required from the drag source.
*
* <p>The following fields in the DragSourceEvent apply:
* <ul>
* <li>(in)widget
* <li>(in)time
* <li>(in)dataType - the type of data requested.
* <li>(out)data - the application inserts the actual data here (must match the dataType)
* <li>(out)doit - set this to cancel the drag
* </ul></p>
*
* @param event the information associated with the drag set data event
*
* @see DragSourceEvent
*/
public void dragSetData(DragSourceEvent event);
/**
* The drop has successfully completed(mouse up over a valid target) or has been terminated (such as hitting
* the ESC key). Perform cleanup such as removing data from the source side on a successful move operation.
*
* <p>The following fields in the DragSourceEvent apply:
* <ul>
* <li>(in)widget
* <li>(in)time
* <li>(in)doit
* <li>(in)detail
* </ul></p>
*
* @param event the information associated with the drag finished event
*
* @see DragSourceEvent
*/
public void dragFinished(DragSourceEvent event);
}