void MyFrame::OnUpdateUI(wxUpdateUIEvent& event) { if(event.GetId() == ID_BUTTON && !m_textfield->IsEmpty()) { event.Enable(true); } else { event.Enable(false); } }
void MyFrame::OnUpdateUI(wxUpdateUIEvent& event) { if(event.GetId() == ID_MENU_ITEM) { if(wxFileExists(wxT("myfile.txt"))) { event.SetText(wxT("Open myfile.txt")); } else { event.SetText(wxT("Create myfile.txt")); } } }The package library for wxUpdateUIEvent is the wxWidgets library.