diff --git a/include/wx/cocoa/radiobox.h b/include/wx/cocoa/radiobox.h
index 363ffd3a35..959f672e19 100644
--- a/include/wx/cocoa/radiobox.h
+++ b/include/wx/cocoa/radiobox.h
@@ -94,6 +94,8 @@ public:
     // layout parameters
     virtual int GetColumnCount() const;
     virtual int GetRowCount() const;
+protected:
+    virtual wxSize DoGetBestSize() const;
 };
 
 #endif // __WX_COCOA_RADIOBOX_H__
diff --git a/src/cocoa/radiobox.mm b/src/cocoa/radiobox.mm
index 216038e63d..93d5043e47 100644
--- a/src/cocoa/radiobox.mm
+++ b/src/cocoa/radiobox.mm
@@ -107,3 +107,8 @@ int wxRadioBox::GetRowCount() const
     return 0;
 }
 
+wxSize wxRadioBox::DoGetBestSize() const
+{
+    return wxSize(50,50);
+}
+