Ensure the wxVListBox gets the focus when it is clicked upon

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31738 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/vlbox.cpp

@@ -574,6 +574,8 @@ void wxVListBox::OnKeyDown(wxKeyEvent& event)
 
 void wxVListBox::OnLeftDown(wxMouseEvent& event)
 {
+    SetFocus();
+    
     int item = HitTest(event.GetPosition());
 
     if ( item != wxNOT_FOUND )