fixed bug which resulted in generation of spurious EVT_RADIOBOX events when a radiobox button was focused but not selected (patch 1739140) [backport of rev 47124 from trunk]

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@47125 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/radiobox.cpp

@@ -270,9 +270,14 @@ bool wxRadioBox::MSWCommand(WXUINT cmd, WXWORD id)
         const unsigned int count = GetCount();
         for ( unsigned int i = 0; i < count; i++ )
         {
-            if ( id == wxGetWindowId((*m_radioButtons)[i]) )
+            const HWND hwndBtn = (*m_radioButtons)[i];
+            if ( id == wxGetWindowId(hwndBtn) )
             {
-                selectedButton = i;
+                // we can get BN_CLICKED for a button which just became focused
+                // but it may not be checked, in which case we shouldn't
+                // generate a radiobox selection changed event for it
+                if ( ::SendMessage(hwndBtn, BM_GETCHECK, 0, 0) == BST_CHECKED )
+                    selectedButton = i;
 
                 break;
             }