diff --git a/src/generic/infobar.cpp b/src/generic/infobar.cpp
index 9d270e9735..7da357176e 100644
--- a/src/generic/infobar.cpp
+++ b/src/generic/infobar.cpp
@@ -275,6 +275,8 @@ void wxInfoBarGeneric::AddButton(wxWindowID btnid, const wxString& label)
 #endif // __WXMAC__
 
     sizer->Add(button, wxSizerFlags().Centre().DoubleBorder());
+    if ( IsShown() )
+        sizer->Layout();
 }
 
 size_t wxInfoBarGeneric::GetButtonCount() const