Added callback in DragSource so that the source can reject the target

before the target even gets a chance to ask if the drop is ok with it.


git-svn-id: https://samskivert.googlecode.com/svn/trunk@1134 6335cc39-0255-0410-8fd6-9bcaacd3b74c

projects/samskivert/src/java/com/samskivert/swing/dnd/DnDManager.java

@@ -1,5 +1,5 @@
 //
-// $Id: DnDManager.java,v 1.18 2003/05/15 22:02:11 mdb Exp $
+// $Id: DnDManager.java,v 1.19 2003/05/20 17:35:51 ray Exp $
 
 package com.samskivert.swing.dnd;
 
@@ -228,6 +228,7 @@ public class DnDManager
             target = (comp == _sourceComp) ? null
                                            : (DropTarget) _droppers.get(comp);
             if ((target != null) && comp.isEnabled() &&
+                _source.checkDrop(target) &&
                 target.checkDrop(_source, _data[0])) {
                 return target;
             }

projects/samskivert/src/java/com/samskivert/swing/dnd/DragSource.java

@@ -1,5 +1,5 @@
 //
-// $Id: DragSource.java,v 1.1 2002/08/20 02:49:19 ray Exp $
+// $Id: DragSource.java,v 1.2 2003/05/20 17:35:51 ray Exp $
 
 package com.samskivert.swing.dnd;
 
@@ -24,6 +24,12 @@ public interface DragSource
      */
     public boolean startDrag (Cursor[] cursors, Object[] data);
 
+    /**
+     * Is the drop target an acceptable one?
+     * @param a potential DropTarget
+     */
+    public boolean checkDrop (DropTarget target);
+
     /**
      * A callback to let the source know that the drop completed successfully.
      */