Changeset 239

Timestamp:

Jan 11, 2011, 11:20:51 PM (15 years ago)

Author:

dmik

Message:

jdk: Fixed wrong message order during Drag & Drop that could lead to a stuck drag operation (the user could not start a new drag session because the previous one would never finish despite the processed drop action).

Location:

trunk/openjdk/jdk/src/windows/native/sun/windows

Files:

• awt_Toolkit.cpp (modified) (2 diffs)
• awt_Toolkit.h (modified) (1 diff)

trunk/openjdk/jdk/src/windows/native/sun/windows/awt_Toolkit.cpp

@@ -1166 +1166 @@
 }
 
+BOOL
+AwtToolkit::SecondaryPeekMessageFunc(MSG& msg) {
+    /*
+     * During DnD, it is possible that while running a secondary message loop
+     * waiting for a quit message from the Java event handler thread (that is
+     * processing the IDropSource::GiveFeedback() callback), another
+     * WM_MOUSEMOVE message comes to the AWT thread's message queue before the
+     * quit message from the Java event handler thread (sent as a result of the
+     * WToolkit::quitSecondaryEventLoop call). This will create another nested
+     * secondary message loop that will eat this outer quit message (together
+     * with its own quit message) which will a) break the message flow and b)
+     * leave the outer loop running forever (so that no new DnD session will be
+     * possible). A solution is similar to the one from
+     * AwtDataTransferer::SecondaryMessageLoop(). Given that
+     * WToolkit::startSecondaryEventLoop() isn't actually used for anything else
+     * but DnD, this solution should work fine.
+     */
+    return ::PeekMessage(&msg, NULL, WM_QUIT, WM_QUIT, PM_REMOVE) ||
+           ::PeekMessage(&msg, NULL, WM_AWT_INVOKE_METHOD, WM_AWT_INVOKE_VOID_METHOD, PM_REMOVE) ||
+           ::PeekMessage(&msg, NULL, WM_PAINT, WM_PAINT, PM_REMOVE);
+}
+
 /*
  * Perform pre-processing on a message before it is translated &
@@ -1735 +1757 @@
 
     AwtToolkit::GetInstance().MessageLoop(AwtToolkit::SecondaryIdleFunc,
-                                          AwtToolkit::CommonPeekMessageFunc);
+                                          AwtToolkit::SecondaryPeekMessageFunc);
 
     CATCH_BAD_ALLOC;

trunk/openjdk/jdk/src/windows/native/sun/windows/awt_Toolkit.h

@@ -374 +374 @@
     static VOID CALLBACK SecondaryIdleFunc();
     static BOOL CALLBACK CommonPeekMessageFunc(MSG& msg);
+    static BOOL CALLBACK SecondaryPeekMessageFunc(MSG& msg);
     static BOOL activateKeyboardLayout(HKL hkl);