Further fixes to widget masking

If mask was set to a widget before the widget was shown,
the mask was not applied.

Also, if toplevel widgets were set a mask in Windows, the mask was
applied to frame coordinates instead of client coordinates.

Ported relevant code from Qt4 to fix these issues.

Change-Id: Id6187cf4952b81b5b60c167e2fd284b7dc83ed9c
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowswindow.cpp b/src/plugins/platforms/windows/qwindowswindow.cpp
index a7140a3d6d..2b86113387 100644
--- a/src/plugins/platforms/windows/qwindowswindow.cpp
+++ b/src/plugins/platforms/windows/qwindowswindow.cpp
@@ -1392,6 +1392,13 @@ void QWindowsWindow::setMask(const QRegion &region)
          return;
     }
     const HRGN winRegion = qRegionToWinRegion(region);
+
+    // Mask is in client area coordinates, so offset it in case we have a frame
+    if (window()->isTopLevel()) {
+        const QMargins margins = frameMargins();
+        OffsetRgn(winRegion, margins.left(), margins.top());
+    }
+
     // SetWindowRgn takes ownership.
     if (!SetWindowRgn(m_data.hwnd, winRegion, true))
         DeleteObject(winRegion);