Bug 610829 Should associate default IMC at committing or canceling composition r=emk

widget/src/windows/nsIMM32Handler.cpp

@@ -293,11 +293,21 @@ nsIMM32Handler::CommitComposition(nsWindow* aWindow, PRBool aForce)
   if (!aForce && !IsComposingWindow(aWindow)) {
     return;
   }
+
+  PRBool associated = aWindow->AssociateDefaultIMC(PR_TRUE);
+  PR_LOG(gIMM32Log, PR_LOG_ALWAYS,
+    ("IMM32: CommitComposition, associated=%s\n",
+     associated ? "YES" : "NO"));
+
   nsIMEContext IMEContext(aWindow->GetWindowHandle());
   if (IMEContext.IsValid()) {
     ::ImmNotifyIME(IMEContext.get(), NI_COMPOSITIONSTR, CPS_COMPLETE, 0);
     ::ImmNotifyIME(IMEContext.get(), NI_COMPOSITIONSTR, CPS_CANCEL, 0);
   }
+
+  if (associated) {
+    aWindow->AssociateDefaultIMC(PR_FALSE);
+  }
 }
 
 /* static */ void
@@ -314,10 +324,20 @@ nsIMM32Handler::CancelComposition(nsWindow* aWindow, PRBool aForce)
   if (!aForce && !IsComposingWindow(aWindow)) {
     return;
   }
+
+  PRBool associated = aWindow->AssociateDefaultIMC(PR_TRUE);
+  PR_LOG(gIMM32Log, PR_LOG_ALWAYS,
+    ("IMM32: CancelComposition, associated=%s\n",
+     associated ? "YES" : "NO"));
+
   nsIMEContext IMEContext(aWindow->GetWindowHandle());
   if (IMEContext.IsValid()) {
     ::ImmNotifyIME(IMEContext.get(), NI_COMPOSITIONSTR, CPS_CANCEL, 0);
   }
+
+  if (associated) {
+    aWindow->AssociateDefaultIMC(PR_FALSE);
+  }
 }
 
 /* static */ PRBool

widget/src/windows/nsIMM32Handler.h

@@ -131,6 +131,14 @@ public:
 
   static PRBool CanOptimizeKeyAndIMEMessages(MSG *aNextKeyOrIMEMessage);
 
+#ifdef DEBUG
+  /**
+   * IsIMEAvailable() returns TRUE when current keyboard layout has IME.
+   * Otherwise, FALSE.
+   */
+  static PRBool IsIMEAvailable() { return sIsIME; }
+#endif
+
   // If aForce is TRUE, these methods doesn't check whether we have composition
   // or not.  If you don't set it to TRUE, these method doesn't commit/cancel
   // the composition on uexpected window.

widget/src/windows/nsWindow.cpp

@@ -370,7 +370,6 @@ nsWindow::nsWindow() : nsBaseWidget()
   mWnd                  = nsnull;
   mPaintDC              = nsnull;
   mPrevWndProc          = nsnull;
-  mOldIMC               = nsnull;
   mNativeDragTarget     = nsnull;
   mInDtor               = PR_FALSE;
   mIsVisible            = PR_FALSE;
@@ -6669,7 +6668,7 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
   static PRBool sRedirectedKeyDownEventPreventedDefault = PR_FALSE;
   PRBool noDefault;
   if (aFakeCharMessage || !IsRedirectedKeyDownMessage(aMsg)) {
-    HIMC oldIMC = mOldIMC;
+    nsIMEContext IMEContext(mWnd);
     noDefault =
       DispatchKeyEvent(NS_KEY_DOWN, 0, nsnull, DOMKeyCode, &aMsg, aModKeyState);
     if (aEventDispatched) {
@@ -6685,8 +6684,9 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
     // application, we shouldn't redirect the message to it because the keydown
     // message is processed by us, so, nobody shouldn't process it.
     HWND focusedWnd = ::GetFocus();
-    if (!noDefault && !aFakeCharMessage && oldIMC && !mOldIMC && focusedWnd &&
-        !PluginHasFocus()) {
+    nsIMEContext newIMEContext(mWnd);
+    if (!noDefault && !aFakeCharMessage && focusedWnd && !PluginHasFocus() &&
+        !IMEContext.get() && newIMEContext.get()) {
       RemoveNextCharMessage(focusedWnd);
 
       INPUT keyinput;
@@ -7315,11 +7315,8 @@ void nsWindow::OnDestroy()
     CaptureRollupEvents(nsnull, nsnull, PR_FALSE, PR_TRUE);
   }
 
-  // If IME is disabled, restore it.
-  if (mOldIMC) {
-    mOldIMC = ::ImmAssociateContext(mWnd, mOldIMC);
-    NS_ASSERTION(!mOldIMC, "Another IMC was associated");
-  }
+  // Restore the IM context.
+  AssociateDefaultIMC(PR_TRUE);
 
   // Turn off mouse trails if enabled.
   MouseTrailer* mtrailer = nsToolkit::gMouseTrailer;
@@ -7958,11 +7955,7 @@ NS_IMETHODIMP nsWindow::SetInputMode(const IMEContext& aContext)
   PRBool enable = (status == nsIWidget::IME_STATUS_ENABLED ||
                    status == nsIWidget::IME_STATUS_PLUGIN);
 
-  if (!enable != !mOldIMC)
-    return NS_OK;
-  mOldIMC = ::ImmAssociateContext(mWnd, enable ? mOldIMC : NULL);
-  NS_ASSERTION(!enable || !mOldIMC, "Another IMC was associated");
-
+  AssociateDefaultIMC(enable);
   return NS_OK;
 }
 
@@ -8025,6 +8018,42 @@ nsWindow::OnIMESelectionChange(void)
 }
 #endif //NS_ENABLE_TSF
 
+PRBool nsWindow::AssociateDefaultIMC(PRBool aAssociate)
+{
+  nsIMEContext IMEContext(mWnd);
+
+  if (aAssociate) {
+    BOOL ret = ::ImmAssociateContextEx(mWnd, NULL, IACE_DEFAULT);
+#ifdef DEBUG
+    // Note that if IME isn't available with current keyboard layout,
+    // IMM might not be installed on the system such as English Windows.
+    // On such system, IMM APIs always fail.
+    NS_ASSERTION(ret || !nsIMM32Handler::IsIMEAvailable(),
+                 "ImmAssociateContextEx failed to restore default IMC");
+    if (ret) {
+      nsIMEContext newIMEContext(mWnd);
+      NS_ASSERTION(!IMEContext.get() || newIMEContext.get() == IMEContext.get(),
+                   "Unknown IMC had been associated");
+    }
+#endif
+    return ret && !IMEContext.get();
+  }
+
+  if (mOnDestroyCalled) {
+    // If OnDestroy() has been called, we shouldn't disassociate the default
+    // IMC at destroying the window.
+    return PR_FALSE;
+  }
+
+  if (!IMEContext.get()) {
+    return PR_FALSE; // already disassociated
+  }
+
+  BOOL ret = ::ImmAssociateContextEx(mWnd, NULL, 0);
+  NS_ASSERTION(ret, "ImmAssociateContextEx failed to disassociate the IMC");
+  return ret != FALSE;
+}
+
 #ifdef ACCESSIBILITY
 
 #ifdef DEBUG_WMGETOBJECT

widget/src/windows/nsWindow.h

@@ -262,6 +262,21 @@ public:
    */
   static void             StartAllowingD3D9(bool aReinitialize);
 
+  /**
+   * AssociateDefaultIMC() associates or disassociates the default IMC for
+   * the window.
+   *
+   * @param aAssociate    TRUE, associates the default IMC with the window.
+   *                      Otherwise, disassociates the default IMC from the
+   *                      window.
+   * @return              TRUE if this method associated the default IMC with
+   *                      disassociated window or disassociated the default IMC
+   *                      from associated window.
+   *                      Otherwise, i.e., if this method did nothing actually,
+   *                      FALSE.
+   */
+  PRBool                  AssociateDefaultIMC(PRBool aAssociate);
+
 #if MOZ_WINSDK_TARGETVER >= MOZ_NTDDI_WIN7
   PRBool HasTaskbarIconBeenCreated() { return mHasTaskbarIconBeenCreated; }
   // Called when either the nsWindow or an nsITaskbarTabPreview receives the noticiation that this window
@@ -504,7 +519,6 @@ protected:
   PRUint32              mBlurSuppressLevel;
   DWORD_PTR             mOldStyle;
   DWORD_PTR             mOldExStyle;
-  HIMC                  mOldIMC;
   IMEContext            mIMEContext;
   nsNativeDragTarget*   mNativeDragTarget;
   HKL                   mLastKeyboardLayout;