only erase background if we do have a non-default background set

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@61127 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/src/osx/window_osx.cpp b/src/osx/window_osx.cpp
index cb59ce7889d7fd00e189fe231dc6ab3e63effe14..5ba3fcaf50a1e7a8bb056f1e41126709a6859c07 100644 (file)
--- a/src/osx/window_osx.cpp
+++ b/src/osx/window_osx.cpp
@@ -1778,7 +1778,7 @@ bool wxWindowMac::MacDoRedraw( long time )
                         break;
                 }
 
-                if ( MacGetTopLevelWindow() )
+                if ( UseBgCol() && MacGetTopLevelWindow() )
                 {
                     dc.SetBackground(GetBackgroundColour());
                     dc.Clear();