#include <wx/wx.h>

class myApp : public wxApp {
 public:
   bool OnInit(void);
   int OnExit(void);
};

IMPLEMENT_APP(myApp)

bool myApp :: OnInit(){

   wxFrame* frame = new wxFrame(NULL, wxID_ANY, wxT("blah blah"));
   wxBoxSizer* sizer = new wxBoxSizer( wxHORIZONTAL );

   wxPanel* panel = new wxPanel(frame, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxTAB_TRAVERSAL);
   
   wxBoxSizer* panelSizer = new wxBoxSizer(wxVERTICAL);
   
   wxComboBox* combo;

   combo = new wxComboBox(panel, wxID_ANY);
   combo->Append(wxT("1.1"));
   combo->Append(wxT("1.2"));
   combo->Append(wxT("1.3"));
   panelSizer->Add(combo, 0, wxEXPAND | wxALL, 2);

   combo = new wxComboBox(panel, wxID_ANY);
   combo->Append(wxT("2.1"));
   combo->Append(wxT("2.2"));
   combo->Append(wxT("2.3"));
   combo->Append(wxT("2.4"));
   combo->Append(wxT("2.5"));
   panelSizer->Add(combo, 0, wxEXPAND | wxALL, 2);

   combo = new wxComboBox(panel, wxID_ANY);
   combo->Append(wxT("3.1"));
   combo->Append(wxT("3.2"));
   combo->Append(wxT("3.3"));
   combo->Append(wxT("3.4"));
   panelSizer->Add(combo, 0, wxEXPAND | wxALL, 2);

   combo = new wxComboBox(panel, wxID_ANY);
   combo->Append(wxT("4.1"));
   combo->Append(wxT("4.2"));
   panelSizer->Add(combo, 0, wxEXPAND | wxALL, 2);

   panelSizer->Add(new wxButton(panel, wxID_ANY, wxT("label")), 0, wxEXPAND | wxALL, 2);

   panel->SetSizer(panelSizer);
   panel->SetFocus();
   
   sizer->Add(panel, 1, wxEXPAND | wxALL);
   frame->SetSizer(sizer);
   frame->Show();
   this->SetTopWindow(frame);

   return true;
}

int myApp :: OnExit(){
  
   return 0;
}