src/macosx/classes/sun/lwawt/macosx/CDropTargetContextPeer.java

*** 24,33 ****
--- 24,34 ----
   */
  
  package sun.lwawt.macosx;
  
  import java.awt.*;
+ import java.awt.dnd.DropTarget;
  
  import sun.awt.dnd.SunDropTargetContextPeer;
  import sun.awt.dnd.SunDropTargetEvent;
  
  import javax.swing.*;
*** 36,46 ****
  final class CDropTargetContextPeer extends SunDropTargetContextPeer {
  
      private long    fNativeDropTransfer = 0;
      private long    fNativeDataAvailable = 0;
      private Object  fNativeData    = null;
!     private boolean insideTarget = true;
  
      Object awtLockAccess = new Object();
  
      static CDropTargetContextPeer getDropTargetContextPeer() {
          return new CDropTargetContextPeer();
--- 37,47 ----
  final class CDropTargetContextPeer extends SunDropTargetContextPeer {
  
      private long    fNativeDropTransfer = 0;
      private long    fNativeDataAvailable = 0;
      private Object  fNativeData    = null;
!     private DropTarget insideTarget = null;
  
      Object awtLockAccess = new Object();
  
      static CDropTargetContextPeer getDropTargetContextPeer() {
          return new CDropTargetContextPeer();
*** 86,133 ****
          }
  
          return fNativeData;
      }
  
!     // We need to take care of dragExit message because for some reason it is not being
!     // generated for lightweight components
      @Override
      protected void processMotionMessage(SunDropTargetEvent event, boolean operationChanged) {
!         Component eventSource = (Component)event.getComponent();
!         Point screenPoint = event.getPoint();
!         SwingUtilities.convertPointToScreen(screenPoint, eventSource);
!         Rectangle screenBounds = new Rectangle(eventSource.getLocationOnScreen().x,
!                 eventSource.getLocationOnScreen().y,
!                 eventSource.getWidth(), eventSource.getHeight());
!         if(insideTarget) {
!             if(!screenBounds.contains(screenPoint)) {
                  processExitMessage(event);
-                 insideTarget = false;
                  return;
              }
          } else {
!             if(screenBounds.contains(screenPoint)) {
                  processEnterMessage(event);
-                 insideTarget = true;
              } else {
                  return;
              }
          }
          super.processMotionMessage(event, operationChanged);
      }
  
      @Override
      protected void processDropMessage(SunDropTargetEvent event) {
!         Component eventSource = (Component)event.getComponent();
          Point screenPoint = event.getPoint();
          SwingUtilities.convertPointToScreen(screenPoint, eventSource);
          Rectangle screenBounds = new Rectangle(eventSource.getLocationOnScreen().x,
                  eventSource.getLocationOnScreen().y,
                  eventSource.getWidth(), eventSource.getHeight());
!         if(screenBounds.contains(screenPoint)) {
!             super.processDropMessage(event);
!         }
      }
  
      @Override
      protected int postDropTargetEvent(Component component, int x, int y, int dropAction,
                                        int actions, long[] formats, long nativeCtxt, int eventID,
--- 87,160 ----
          }
  
          return fNativeData;
      }
  
!     // We need to take care of dragEnter and dragExit messages because
!     // native system generates them only for heavyweights
      @Override
      protected void processMotionMessage(SunDropTargetEvent event, boolean operationChanged) {
!         boolean eventInsideTarget = isEventInsideTarget(event);
!         if(event.getComponent().getDropTarget() == insideTarget) {
!             if(!eventInsideTarget) {
                  processExitMessage(event);
                  return;
              }
          } else {
!             if(eventInsideTarget) {
                  processEnterMessage(event);
              } else {
                  return;
              }
          }
          super.processMotionMessage(event, operationChanged);
      }
  
+     /**
+      * Could be called when DnD enters a heavyweight or synthesized in processMotionMessage
+      */
+     @Override
+     protected void processEnterMessage(SunDropTargetEvent event) {
+         Component c = event.getComponent();
+         DropTarget dt = event.getComponent().getDropTarget();
+         if (isEventInsideTarget(event)
+                 && dt != insideTarget
+                 && c.isShowing()
+                 && dt != null
+                 && dt.isActive()) {
+             insideTarget = dt;
+             super.processEnterMessage(event);
+         }
+     }
+ 
+     /**
+      * Could be called when DnD exits a heavyweight or synthesized in processMotionMessage
+      */
+     @Override
+     protected void processExitMessage(SunDropTargetEvent event) {
+         if(event.getComponent().getDropTarget() == insideTarget) {
+             insideTarget = null;
+             super.processExitMessage(event);
+         }
+     }
+ 
      @Override
      protected void processDropMessage(SunDropTargetEvent event) {
!         if(isEventInsideTarget(event)) {
!             super.processDropMessage(event);
!             insideTarget = null;
!         }
!     }
! 
!     private boolean isEventInsideTarget(SunDropTargetEvent event) {
!         Component eventSource = event.getComponent();
          Point screenPoint = event.getPoint();
          SwingUtilities.convertPointToScreen(screenPoint, eventSource);
          Rectangle screenBounds = new Rectangle(eventSource.getLocationOnScreen().x,
                  eventSource.getLocationOnScreen().y,
                  eventSource.getWidth(), eventSource.getHeight());
!         return screenBounds.contains(screenPoint);
      }
  
      @Override
      protected int postDropTargetEvent(Component component, int x, int y, int dropAction,
                                        int actions, long[] formats, long nativeCtxt, int eventID,