--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwt/dnd/DropTargetListener.d	Sat Aug 09 17:00:02 2008 +0200
@@ -0,0 +1,250 @@
+/*******************************************************************************
+ * 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
+ *******************************************************************************/
+module dwt.dnd;
+
+import dwt.internal.DWTEventListener;
+
+/**
+ * The <code>DropTargetListener</code> class provides event notification to the application 
+ * for DropTarget events.
+ *
+ * <p>As the user moves the cursor into, over and out of a Control that has been designated 
+ * as a DropTarget, events indicate what operation can be performed and what data can be 
+ * transferred if a drop where to occur at that point.
+ * The application can respond to these events and change the type of data that will 
+ * be dropped by modifying event.currentDataType, or change the operation that will be performed 
+ * by modifying the event.detail field or stop any drop from happening on the current target
+ * by setting the event.detail field to DND_DROP_NONE.</p>
+ *
+ * <p>When the user causes a drop to happen by releasing the mouse over a valid drop target, 
+ * the application has one last chance to change the data type of the drop through the 
+ * DropAccept event.  If the drop is still allowed, the DropAccept event is immediately 
+ * followed by the Drop event.  In the Drop event, the application can still change the
+ * operation that is performed but the data type is fixed.</p>
+ * 
+ * @see DropTargetEvent
+ *
+ */
+public interface DropTargetListener : DWTEventListener {
+    
+/**
+ * The cursor has entered the drop target boundaries.
+ *
+ * <p>The following fields in the DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x
+ * <li>(in)y
+ * <li>(in)dataTypes
+ * <li>(in,out)currentDataType
+ * <li>(in)operations
+ * <li>(in,out)detail
+ * <li>(in,out)feedback
+ * </ul></p>
+ *
+ * <p>The <code>operation</code> value is determined by the modifier keys pressed by the user.  
+ * If no keys are pressed the <code>event.detail</code> field is set to DND.DROP_DEFAULT.  
+ * If the application does not set the <code>event.detail</code> to something other 
+ * than <code>DND.DROP_DEFAULT</code> the operation will be set to the platform defined standard 
+ * default.</p>
+ * 
+ * <p>The <code>currentDataType</code> is determined by the first transfer agent specified in 
+ * setTransfer() that matches a data type provided by the drag source.</p>
+ * 
+ * <p>It is possible to get a DragEnter event when the drag source does not provide any matching data.
+ * In this case, the default operation is DND.DROP_NONE and the currentDataType is null.</p>
+ * 
+ * <p>The application can change the operation that will be performed by modifying the 
+ * <code>detail</code> field but the choice must be one of the values in the <code>operations</code> 
+ * field or DND.DROP_NONE.</p>
+ * 
+ * <p>The application can also change the type of data being requested by 
+ * modifying the <code>currentDataTypes</code> field  but the value must be one of the values 
+ * in the <code>dataTypes</code> list.</p>
+ *
+ * @param event  the information associated with the drag enter event
+ * 
+ * @see DropTargetEvent
+ */
+public void dragEnter(DropTargetEvent event);
+
+/**
+ * The cursor has left the drop target boundaries OR the drop has been cancelled OR the data 
+ * is about to be dropped.
+ *
+ * <p>The following fields in the DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x
+ * <li>(in)y
+ * <li>(in)dataTypes
+ * <li>(in)currentDataType
+ * <li>(in)operations
+ * <li>(in)detail
+ * </ul></p>
+ *
+ * @param event  the information associated with the drag leave event
+ *
+ * @see DropTargetEvent
+ */
+public void dragLeave(DropTargetEvent event);
+
+/**
+ * The operation being performed has changed (usually due to the user changing the selected modifier key(s)
+ * while dragging).
+ *
+ * <p>The following fields in the DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x
+ * <li>(in)y
+ * <li>(in)dataTypes
+ * <li>(in,out)currentDataType
+ * <li>(in)operations
+ * <li>(in,out)detail
+ * <li>(in,out)feedback
+ * </ul></p>
+ *
+ * <p>The <code>operation</code> value is determined by the modifier keys pressed by the user.  
+ * If no keys are pressed the <code>event.detail</code> field is set to DND.DROP_DEFAULT.  
+ * If the application does not set the <code>event.detail</code> to something other than 
+ * <code>DND.DROP_DEFAULT</code> the operation will be set to the platform defined standard default.</p>
+ * 
+ * <p>The <code>currentDataType</code> value is determined by the value assigned to 
+ * <code>currentDataType</code> in previous dragEnter and dragOver calls.</p>
+ * 
+ * <p>The application can change the operation that will be performed by modifying the 
+ * <code>detail</code> field but the choice must be one of the values in the <code>operations</code> 
+ * field.</p>
+ * 
+ * <p>The application can also change the type of data being requested by modifying 
+ * the <code>currentDataTypes</code> field  but the value must be one of the values in the 
+ * <code>dataTypes</code> list.</p>
+ *
+ * @param event  the information associated with the drag operation changed event
+ * 
+ * @see DropTargetEvent
+ */
+public void dragOperationChanged(DropTargetEvent event);
+
+/**
+ * The cursor is moving over the drop target.
+ *
+ * <p>The following fields in the DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x
+ * <li>(in)y
+ * <li>(in)dataTypes
+ * <li>(in,out)currentDataType
+ * <li>(in)operations
+ * <li>(in,out)detail
+ * <li>(in,out)feedback
+ * </ul></p>
+ *
+ * <p>The <code>operation</code> value is determined by the value assigned to 
+ * <code>currentDataType</code> in previous dragEnter and dragOver calls.</p>
+ * 
+ * <p>The <code>currentDataType</code> value is determined by the value assigned to 
+ * <code>currentDataType</code> in previous dragEnter and dragOver calls.</p>
+ * 
+ * <p>The application can change the operation that will be performed by modifying the 
+ * <code>detail</code> field but the choice must be one of the values in the <code>operations</code> 
+ * field.</p>
+ * 
+ * <p>The application can also change the type of data being requested by modifying the 
+ * <code>currentDataTypes</code> field  but the value must be one of the values in the 
+ * <code>dataTypes</code> list.</p>
+ * 
+ * <p>NOTE: At this point the <code>data</code> field is null.  On some platforms, it is possible 
+ * to obtain the data being transferred before the transfer occurs but in most platforms this is 
+ * not possible.  On those platforms where the data is available, the application can access the 
+ * data as follows:</p>
+ * 
+ * <pre><code>
+ * public void dragOver(DropTargetEvent event) {
+ *       TextTransfer textTransfer = TextTransfer.getInstance();
+ *       String data = (String)textTransfer.nativeToJava(event.currentDataType);
+ *       if (data !is null) {
+ *           System.out.println("Data to be dropped is (Text)"+data);
+ *       }
+ * };
+ * </code></pre>
+ *
+ * @param event  the information associated with the drag over event
+ * 
+ * @see DropTargetEvent
+ */
+public void dragOver(DropTargetEvent event);
+
+/**
+ * The data is being dropped.  The data field contains java format of the data being dropped.  
+ * To determine the type of the data object, refer to the documentation for the Transfer subclass 
+ * specified in event.currentDataType.
+ *
+ * <p>The following fields in DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x 
+ * <li>(in)y
+ * <li>(in,out)detail
+ * <li>(in)currentDataType
+ * <li>(in)data
+ * </ul></p>
+ *
+ * <p>The application can refuse to perform the drop operation by setting the detail 
+ * field to DND.DROP_NONE.</p>
+ *
+ * @param event the information associated with the drop event
+ * 
+ * @see DropTargetEvent
+ */
+public void drop(DropTargetEvent event);
+
+/**
+ * The drop is about to be performed.  
+ * The drop target is given a last chance to change the nature of the drop.
+ * 
+ * <p>The following fields in the DropTargetEvent apply:
+ * <ul>
+ * <li>(in)widget
+ * <li>(in)time
+ * <li>(in)x
+ * <li>(in)y
+ * <li>(in)dataTypes
+ * <li>(in,out)currentDataType
+ * <li>(in)operations
+ * <li>(in,out)detail
+ * </ul></p>
+ *
+ * <p>The application can veto the drop by setting the <code>event.detail</code> field to 
+ * <code>DND.DROP_NONE</code>.</p>
+ *
+ * <p>The application can change the operation that will be performed by modifying the 
+ * <code>detail</code> field but the choice must be one of the values in the 
+ * <code>operations</code> field.</p>
+ * 
+ * <p>The application can also change the type of data being requested by modifying the 
+ * <code>currentDataTypes</code> field  but the value must be one of the values in the <
+ * code>dataTypes</code> list.</p>
+ *
+ * @param event  the information associated with the drop accept event
+ * 
+ * @see DropTargetEvent
+ */
+public void dropAccept(DropTargetEvent event);
+
+}