wxGUI: set background color for LayerTree and CTreeView to white (wxPython 3)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@64141 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/gui_core/treeview.py

@@ -138,6 +138,7 @@ class CTreeView(AbstractTreeViewMixin, CT.CustomTreeCtrl):
             kw[style] = CT.TR_HIDE_ROOT | CT.TR_FULL_ROW_HIGHLIGHT |\
                 CT.TR_HAS_BUTTONS | CT.TR_LINES_AT_ROOT | CT.TR_SINGLE
         super(CTreeView, self).__init__(parent=parent, model=model, **kw)
+        self.SetBackgroundColour("white")
         self.RefreshItems()
         
 class TreeListView(AbstractTreeViewMixin, ExpansionState, gizmos.TreeListCtrl):

gui/wxpython/lmgr/layertree.py

@@ -159,6 +159,7 @@ class LayerTree(treemixin.DragAndDrop, CT.CustomTreeCtrl):
         else:
             super(LayerTree, self).__init__(parent, id, style = ctstyle, **kwargs)
         self.SetName("LayerTree")
+        self.SetBackgroundColour("white")
         
         ### SetAutoLayout() causes that no vertical scrollbar is displayed
         ### when some layers are not visible in layer tree