Prevent window caption flashing in the magic frames by handling undocumented windows messages that get sent to caption'ed windows.

B=1031854

Review URL: http://codereview.chromium.org/1965

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@2105 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 45 insertions, 0 deletions

diff --git a/chrome/views/custom_frame_window.cc b/chrome/views/custom_frame_window.cc
index 2f00a88..12d0a5b 100644
--- a/chrome/views/custom_frame_window.cc
+++ b/chrome/views/custom_frame_window.cc
@@ -1105,6 +1105,24 @@ void CustomFrameWindow::OnNCLButtonDown(UINT ht_component,
   }
 }
 
+LRESULT CustomFrameWindow::OnNCUAHDrawCaption(UINT msg, WPARAM w_param,
+                                              LPARAM l_param) {
+  // See comment in hwnd_view_container.h at the definition of
+  // WM_NCUAHDRAWCAPTION for an explanation about why we need to handle this
+  // message.
+  SetMsgHandled(TRUE);
+  return 0;
+}
+
+LRESULT CustomFrameWindow::OnNCUAHDrawFrame(UINT msg, WPARAM w_param,
+                                            LPARAM l_param) {
+  // See comment in hwnd_view_container.h at the definition of
+  // WM_NCUAHDRAWCAPTION for an explanation about why we need to handle this
+  // message.
+  SetMsgHandled(TRUE);
+  return 0;
+}
+
 LRESULT CustomFrameWindow::OnSetCursor(HWND window, UINT hittest_code,
                                        UINT message) {
   int index = RC_NORMAL;
diff --git a/chrome/views/custom_frame_window.h b/chrome/views/custom_frame_window.h
index d014c91..c8015f1 100644
--- a/chrome/views/custom_frame_window.h
+++ b/chrome/views/custom_frame_window.h
@@ -56,6 +56,8 @@ class CustomFrameWindow : public Window {
   virtual LRESULT OnNCMouseMove(UINT flags, const CPoint& point);
   virtual void OnNCPaint(HRGN rgn);
   virtual void OnNCLButtonDown(UINT ht_component, const CPoint& point);
+  virtual LRESULT OnNCUAHDrawCaption(UINT msg, WPARAM w_param, LPARAM l_param);
+  virtual LRESULT OnNCUAHDrawFrame(UINT msg, WPARAM w_param, LPARAM l_param);
   virtual LRESULT OnSetCursor(HWND window, UINT hittest_code, UINT message);
   virtual void OnSize(UINT param, const CSize& size);
 
diff --git a/chrome/views/hwnd_view_container.h b/chrome/views/hwnd_view_container.h
index 0249183..7cfb000 100644
--- a/chrome/views/hwnd_view_container.h
+++ b/chrome/views/hwnd_view_container.h
@@ -35,6 +35,17 @@ RootView* GetRootViewForHWND(HWND hwnd);
 // lParam - Pointer to MSG struct containing the original message.
 static const int kReflectedMessage = WM_APP + 3;
 
+// These two messages aren't defined in winuser.h, but they are sent to windows
+// with captions. They appear to paint the window caption and frame.
+// Unfortunately if you override the standard non-client rendering as we do
+// with CustomFrameWindow, sometimes Windows (not deterministically
+// reproducibly but definitely frequently) will send these messages to the
+// window and paint the standard caption/title over the top of the custom one.
+// So we need to handle these messages in CustomFrameWindow to prevent this
+// from happening.
+static const int WM_NCUAHDRAWCAPTION = 0xAE;
+static const int WM_NCUAHDRAWFRAME = 0xAF;
+
 ///////////////////////////////////////////////////////////////////////////////
 //
 // FillLayout
@@ -159,6 +170,10 @@ class HWNDViewContainer : public ViewContainer,
 
     // Reflected message handler
     MESSAGE_HANDLER_EX(kReflectedMessage, OnReflectedMessage)
+
+    // CustomFrameWindow hacks
+    MESSAGE_HANDLER_EX(WM_NCUAHDRAWCAPTION, OnNCUAHDrawCaption)
+    MESSAGE_HANDLER_EX(WM_NCUAHDRAWFRAME, OnNCUAHDrawFrame)
     
     // Non-atlcrack.h handlers
     MESSAGE_HANDLER_EX(WM_GETOBJECT, OnGetObject)
@@ -377,6 +392,16 @@ class HWNDViewContainer : public ViewContainer,
   virtual void OnNCRButtonDblClk(UINT flags, const CPoint& point);
   virtual void OnNCRButtonDown(UINT flags, const CPoint& point);
   virtual void OnNCRButtonUp(UINT flags, const CPoint& point);
+  virtual LRESULT OnNCUAHDrawCaption(UINT msg,
+                                     WPARAM w_param,
+                                     LPARAM l_param) {
+    SetMsgHandled(FALSE);
+    return 0;
+  }
+  virtual LRESULT OnNCUAHDrawFrame(UINT msg, WPARAM w_param, LPARAM l_param) {
+    SetMsgHandled(FALSE);
+    return 0;
+  }
   virtual LRESULT OnNotify(int w_param, NMHDR* l_param);
   virtual void OnPaint(HDC dc);
   virtual LRESULT OnPowerBroadcast(DWORD power_event, DWORD data) {