Question

Similar problem to last time. I run the code, exit it. The GUI disappears and it appears to have been fully exited but I check my process list and the code is there still holding memory.

I’ve narrowed it down to a call to wxFileDialog. I don’t understand what I’m doing wrong because I’m calling much in a similar way as I’m calling a wxDialog. The wxDialog call doesn’t result in this problem but the wxFileDialog does cause it.

Works fine:

// Help Dialog
void MyFrame::OnHelp(wxCommandEvent& WXUNUSED(event))
{
    wxBoxSizer *topsizer;
    wxHtmlWindow *html;
    wxDialog dlg(this, wxID_ANY, wxString(_("Help")));

    topsizer = new wxBoxSizer(wxVERTICAL);

    html = new wxHtmlWindow(&dlg, wxID_ANY, wxDefaultPosition,
    wxSize(380, 160), wxHW_SCROLLBAR_NEVER);
    html->SetBorders(0);
    html->LoadPage(wxT("data/help.html"));

    // Fit the HTML window to the size of its contents
    html->SetSize(html->GetInternalRepresentation()->GetWidth(),
                html->GetInternalRepresentation()->GetHeight());

    topsizer->Add(html, 1, wxALL, 10);

    wxButton *but = new wxButton(&dlg, wxID_OK, _("OK"));
    but->SetDefault();

    topsizer->Add(but, 0, wxALL | wxALIGN_RIGHT, 15);

    dlg.SetSizer(topsizer);
    topsizer->Fit(&dlg);

    dlg.CentreOnParent();
    dlg.ShowModal();
}

Causes problem:

void MyFrame::OnVidFile(wxCommandEvent& WXUNUSED(event))
{
    wxString caption = wxT("Choose a file");
    wxString wildcard = wxT("AVI files (*.avi)|*.avi");
    wxString defaultDir = wxGetHomeDir();
    wxString defaultFilename = wxEmptyString;

    wxFileDialog dialog(this, caption, defaultDir, defaultFilename, wildcard, wxOPEN | wxFILE_MUST_EXIST );
    dialog.CentreOnParent();

    if(dialog.ShowModal() == wxID_OK)       // problem
        pathVid = dialog.GetPath().c_str();
}

This results in the program not terminating correctly even if I throw in a dialog.Destroy(); or dialog.Close(); at the end. They look like similar calls to the dialog class to me?

Am I missing something here?

Answer 1

Problem is a conflict with OpenCV (specifically HighGUI).

To avoid this problem and the OLE error problem, override the WxWidgets initialize base class virtual as follows:

bool MywxApp::Initialize( int& argc, wxChar **argv ) 
{ 
  ::CoUninitialize(); 
  return wxApp::Initialize( argc, argv ); 
}