Fixed bug [ 413614 ] native wxDragImage w/o mask is broken

by adding ILC_MASK even when there's no mask.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@17339 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/latex/wx/dragimag.tex

@@ -28,6 +28,14 @@ override \helpref{wxDragImage::DoDrawImage}{wxdragimagedodrawimage} and
 
 Please see {\tt samples/dragimag} for an example.
 
+%\wxheading{Notes}
+%
+%Using the native Windows implementation, you must supply an image with a mask, or
+%the image will not show when dragged. It is not clear if this is a bug
+%in Windows or in the wxDragImage implementation. You can add a mask
+%with a call to wxImage::SetMaskColour, passing RGB values not likely
+%to be in the image. [CURED by creating the ImageList with ILC_MASK]
+
 \wxheading{Derived from}
 
 \helpref{wxObject}{wxobject}

src/msw/dragimag.cpp

@@ -129,7 +129,11 @@ bool wxDragImage::Create(const wxBitmap& image, const wxCursor& cursor)
         flags = ILC_COLOR32;
 
     bool mask = (image.GetMask() != 0);
-    if ( mask )
+
+    // Curiously, even if the image doesn't have a mask,
+    // we still have to use ILC_MASK or the image won't show
+    // up when dragged.
+//    if ( mask )
     flags |= ILC_MASK;
 
     m_hImageList = (WXHIMAGELIST) ImageList_Create(image.GetWidth(), image.GetHeight(), flags, 1, 1);