topsizer->Add(gridsizer, 1, wxGROW | wxALL, 10);
+#if wxUSE_STATLINE
// 3) middle: create wxStaticLine with minimum size (3x3)
topsizer->Add(
new wxStaticLine( this, wxID_ANY, wxDefaultPosition, wxSize(3,3), wxHORIZONTAL),
wxEXPAND | // make horizontally stretchable
wxALL, // and make border all around
5 ); // set border width to 5
+#endif // wxUSE_STATLINE
// 4) bottom: create two centred wxButtons