///////////////////////////////////////////////////////////////////////////// // Name: except.cpp // Purpose: Except wxWidgets sample // Author: Julian Smart // Modified by: // Created: 04/01/98 // RCS-ID: $Id$ // Copyright: (c) Julian Smart // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// // ============================================================================ // declarations // ============================================================================ // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- // For compilers that support precompilation, includes "wx/wx.h". #include "wx/wxprec.h" #ifdef __BORLANDC__ #pragma hdrstop #endif // for all others, include the necessary headers (this file is usually all you // need because it includes almost all "standard" wxWidgets headers) #ifndef WX_PRECOMP #include "wx/log.h" #include "wx/app.h" #include "wx/frame.h" #include "wx/dialog.h" #include "wx/menu.h" #include "wx/button.h" #include "wx/sizer.h" #include "wx/utils.h" #include "wx/msgdlg.h" #endif // ---------------------------------------------------------------------------- // resources // ---------------------------------------------------------------------------- // the application icon (under Windows and OS/2 it is in resources) #if defined(__WXGTK__) || defined(__WXMOTIF__) || defined(__WXMAC__) || defined(__WXMGL__) || defined(__WXX11__) #include "../sample.xpm" #endif // ---------------------------------------------------------------------------- // private classes // ---------------------------------------------------------------------------- // Define a new application type, each program should derive a class from wxApp class MyApp : public wxApp { public: // override base class virtuals // ---------------------------- // program startup virtual bool OnInit(); // 2nd-level exception handling: we get all the exceptions occuring in any // event handler here virtual void HandleEvent(wxEvtHandler *handler, wxEventFunction func, wxEvent& event) const; // 3rd, and final, level exception handling: whenever an unhandled // exception is caught, this function is called virtual void OnUnhandledException(); }; // Define a new frame type: this is going to be our main frame class MyFrame : public wxFrame { public: // ctor(s) MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size, long style = wxDEFAULT_FRAME_STYLE); // event handlers (these functions should _not_ be virtual) void OnQuit(wxCommandEvent& event); void OnAbout(wxCommandEvent& event); void OnDialog(wxCommandEvent& event); void OnThrowString(wxCommandEvent& event); // 1st-level exception handling: we overload ProcessEvent() to be able to // catch exceptions which occur in MyFrame methods here virtual bool ProcessEvent(wxEvent& event); private: // any class wishing to process wxWidgets events must use this macro DECLARE_EVENT_TABLE() }; // A simple dialog which has only some buttons to throw exceptions class MyDialog : public wxDialog { public: MyDialog(wxFrame *parent); // event handlers void OnThrowInt(wxCommandEvent& event); void OnThrowObject(wxCommandEvent& event); private: DECLARE_EVENT_TABLE() }; // A trivial exception class class MyException { public: MyException(const wxString& msg) : m_msg(msg) { } const wxChar *what() const { return m_msg.c_str(); } private: wxString m_msg; }; // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- // IDs for the controls and the menu commands enum { // control ids Except_ThrowInt = 100, Except_ThrowObject, // menu items Except_ThrowString = 200, Except_Dialog, Except_Quit = wxID_EXIT, Except_About = wxID_ABOUT }; // ---------------------------------------------------------------------------- // event tables and other macros for wxWidgets // ---------------------------------------------------------------------------- // the event tables connect the wxWidgets events with the functions (event // handlers) which process them. It can be also done at run-time, but for the // simple menu events like this the static method is much simpler. BEGIN_EVENT_TABLE(MyFrame, wxFrame) EVT_MENU(Except_Quit, MyFrame::OnQuit) EVT_MENU(Except_About, MyFrame::OnAbout) EVT_MENU(Except_Dialog, MyFrame::OnDialog) EVT_MENU(Except_ThrowString, MyFrame::OnThrowString) END_EVENT_TABLE() BEGIN_EVENT_TABLE(MyDialog, wxDialog) EVT_BUTTON(Except_ThrowInt, MyDialog::OnThrowInt) EVT_BUTTON(Except_ThrowObject, MyDialog::OnThrowObject) END_EVENT_TABLE() // Create a new application object: this macro will allow wxWidgets to create // the application object during program execution (it's better than using a // static object for many reasons) and also implements the accessor function // wxGetApp() which will return the reference of the right type (i.e. MyApp and // not wxApp) IMPLEMENT_APP(MyApp) // ============================================================================ // MyApp implementation // ============================================================================ // 'Main program' equivalent: the program execution "starts" here bool MyApp::OnInit() { // create the main application window MyFrame *frame = new MyFrame(_T("Except wxWidgets App"), wxPoint(50, 50), wxSize(450, 340)); // and show it (the frames, unlike simple controls, are not shown when // created initially) frame->Show(true); // success: wxApp::OnRun() will be called which will enter the main message // loop and the application will run. If we returned false here, the // application would exit immediately. return true; } void MyApp::HandleEvent(wxEvtHandler *handler, wxEventFunction func, wxEvent& event) const { try { wxApp::HandleEvent(handler, func, event); } catch ( int i ) { wxLogError(_T("Caught an int %d in MyApp."), i); } } void MyApp::OnUnhandledException() { wxMessageBox(_T("Unhandled exception caught, program will terminate."), _T("wxExcept Sample"), wxOK | wxICON_ERROR); } // ============================================================================ // MyFrame implementation // ============================================================================ // frame constructor MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size, long style) : wxFrame(NULL, wxID_ANY, title, pos, size, style) { // set the frame icon SetIcon(wxICON(sample)); #if wxUSE_MENUS // create a menu bar wxMenu *menuFile = new wxMenu; menuFile->Append(Except_Dialog, _T("Show &dialog\tCtrl-D")); menuFile->Append(Except_ThrowString, _T("Throw a &string\tCtrl-S")); menuFile->AppendSeparator(); menuFile->Append(Except_Quit, _T("E&xit\tCtrl-Q"), _T("Quit this program")); wxMenu *helpMenu = new wxMenu; helpMenu->Append(Except_About, _T("&About...\tF1"), _T("Show about dialog")); // now append the freshly created menu to the menu bar... wxMenuBar *menuBar = new wxMenuBar(); menuBar->Append(menuFile, _T("&File")); menuBar->Append(helpMenu, _T("&Help")); // ... and attach this menu bar to the frame SetMenuBar(menuBar); #endif // wxUSE_MENUS #if wxUSE_STATUSBAR && !defined(__WXWINCE__) // create a status bar just for fun (by default with 1 pane only) CreateStatusBar(2); SetStatusText(_T("Welcome to wxWidgets!")); #endif // wxUSE_STATUSBAR } bool MyFrame::ProcessEvent(wxEvent& event) { try { return wxFrame::ProcessEvent(event); } catch ( const wxChar *msg ) { wxLogMessage(_T("Caught a string \"%s\" in MyFrame"), msg); return true; } } void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event)) { // true is to force the frame to close Close(true); } void MyFrame::OnDialog(wxCommandEvent& WXUNUSED(event)) { try { MyDialog dlg(this); dlg.ShowModal(); } catch ( ... ) { Destroy(); throw; } } void MyFrame::OnThrowString(wxCommandEvent& WXUNUSED(event)) { throw _T("some string"); } void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event)) { wxString msg; msg.Printf( _T("This is the About dialog of the except sample.\n") _T("Welcome to %s"), wxVERSION_STRING); wxMessageBox(msg, _T("About Except"), wxOK | wxICON_INFORMATION, this); } // ============================================================================ // MyDialog implementation // ============================================================================ MyDialog::MyDialog(wxFrame *parent) : wxDialog(parent, wxID_ANY, wxString(_T("Throw exception dialog"))) { wxSizer *sizerTop = new wxBoxSizer(wxVERTICAL); sizerTop->Add(new wxButton(this, Except_ThrowInt, _T("Throw &int")), 0, wxCENTRE | wxALL, 5); sizerTop->Add(new wxButton(this, Except_ThrowObject, _T("Throw &object")), 0, wxCENTRE | wxALL, 5); sizerTop->Add(new wxButton(this, wxID_CANCEL, _T("&Cancel")), 0, wxCENTRE | wxALL, 5); SetSizer(sizerTop); sizerTop->Fit(this); } void MyDialog::OnThrowInt(wxCommandEvent& WXUNUSED(event)) { throw 17; } void MyDialog::OnThrowObject(wxCommandEvent& WXUNUSED(event)) { throw MyException(_T("Exception thrown from the dialog")); }