implement images support for wxButton under XP and later

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@61054 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/button.h

@@ -19,7 +19,7 @@
 class WXDLLIMPEXP_CORE wxButton : public wxButtonBase
 {
 public:
-    wxButton() { }
+    wxButton() { m_imageData = NULL; }
     wxButton(wxWindow *parent,
              wxWindowID id,
              const wxString& label = wxEmptyString,
@@ -29,6 +29,8 @@ public:
              const wxValidator& validator = wxDefaultValidator,
              const wxString& name = wxButtonNameStr)
     {
+        m_imageData = NULL;
+
         Create(parent, id, label, pos, size, style, validator, name);
     }
 
@@ -78,6 +80,13 @@ protected:
     // usually overridden base class virtuals
     virtual wxSize DoGetBestSize() const;
 
+    virtual wxBitmap DoGetBitmap(State which) const;
+    virtual void DoSetBitmap(const wxBitmap& bitmap, State which);
+    virtual void DoSetBitmapMargins(wxCoord x, wxCoord y);
+    virtual void DoSetBitmapPosition(wxDirection dir);
+
+    class wxButtonImageData *m_imageData;
+
 private:
     DECLARE_DYNAMIC_CLASS_NO_COPY(wxButton)
 };