X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/30deac1fa50bd132e57aa386f3c844d275dc95ea..1bd568fa44a864a4110b13e8e0d08f923e5fb4ff:/samples/except/except.cpp?ds=sidebyside diff --git a/samples/except/except.cpp b/samples/except/except.cpp index e0747a4b4c..f401d6ce18 100644 --- a/samples/except/except.cpp +++ b/samples/except/except.cpp @@ -1,11 +1,11 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: except.cpp -// Purpose: Except wxWidgets sample -// Author: Julian Smart +// Name: samples/except/except.cpp +// Purpose: shows how C++ exceptions can be used in wxWidgets +// Author: Vadim Zeitlin // Modified by: -// Created: 04/01/98 +// Created: 2003-09-17 // RCS-ID: $Id$ -// Copyright: (c) Julian Smart +// Copyright: (c) 2003-2005 Vadim Zeitlin // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// @@ -24,6 +24,10 @@ #pragma hdrstop #endif +#if !wxUSE_EXCEPTIONS + #error "This sample only works with wxUSE_EXCEPTIONS == 1" +#endif // !wxUSE_EXCEPTIONS + // 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 @@ -39,6 +43,7 @@ #include "wx/utils.h" #include "wx/msgdlg.h" + #include "wx/icon.h" #endif // ---------------------------------------------------------------------------- @@ -50,6 +55,16 @@ #include "../sample.xpm" #endif +// ---------------------------------------------------------------------------- +// private functions +// ---------------------------------------------------------------------------- + +static void DoCrash() +{ + char *p = 0; + strcpy(p, "Let's crash"); +} + // ---------------------------------------------------------------------------- // private classes // ---------------------------------------------------------------------------- @@ -64,15 +79,26 @@ public: // program startup virtual bool OnInit(); - // 2nd-level exception handling: we get all the exceptions occuring in any + // 2nd-level exception handling: we get all the exceptions occurring in any // event handler here - virtual void HandleEvent(wxEvtHandler *handler, - wxEventFunction func, - wxEvent& event) const; + virtual bool OnExceptionInMainLoop(); // 3rd, and final, level exception handling: whenever an unhandled // exception is caught, this function is called virtual void OnUnhandledException(); + + // and now for something different: this function is called in case of a + // crash (e.g. dereferencing null pointer, division by 0, ...) + virtual void OnFatalException(); + +#ifdef __WXDEBUG__ + // in debug mode, you can override this function to do something different + // (e.g. log the assert to file) whenever an assertion fails + virtual void OnAssert(const wxChar *file, + int line, + const wxChar *cond, + const wxChar *msg); +#endif // __WXDEBUG__ }; // Define a new frame type: this is going to be our main frame @@ -80,19 +106,32 @@ class MyFrame : public wxFrame { public: // ctor(s) - MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size, - long style = wxDEFAULT_FRAME_STYLE); + MyFrame(); // event handlers (these functions should _not_ be virtual) void OnQuit(wxCommandEvent& event); void OnAbout(wxCommandEvent& event); void OnDialog(wxCommandEvent& event); + + void OnThrowInt(wxCommandEvent& event); void OnThrowString(wxCommandEvent& event); + void OnThrowObject(wxCommandEvent& event); + void OnThrowUnhandled(wxCommandEvent& event); + + void OnCrash(wxCommandEvent& event); +#if wxUSE_ON_FATAL_EXCEPTION + void OnHandleCrash(wxCommandEvent& event); +#endif // 1st-level exception handling: we overload ProcessEvent() to be able to // catch exceptions which occur in MyFrame methods here virtual bool ProcessEvent(wxEvent& event); +#ifdef __WXDEBUG__ + // show how an assert failure message box looks like + void OnShowAssert(wxCommandEvent& event); +#endif // __WXDEBUG__ + private: // any class wishing to process wxWidgets events must use this macro DECLARE_EVENT_TABLE() @@ -107,6 +146,7 @@ public: // event handlers void OnThrowInt(wxCommandEvent& event); void OnThrowObject(wxCommandEvent& event); + void OnCrash(wxCommandEvent& event); private: DECLARE_EVENT_TABLE() @@ -124,6 +164,11 @@ private: wxString m_msg; }; +// Another exception class which just has to be different from anything else +class UnhandledException +{ +}; + // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- @@ -131,12 +176,18 @@ private: // IDs for the controls and the menu commands enum { - // control ids - Except_ThrowInt = 100, + // control ids and menu items + Except_ThrowInt = wxID_HIGHEST, + Except_ThrowString, Except_ThrowObject, - - // menu items - Except_ThrowString = 200, + Except_ThrowUnhandled, + Except_Crash, +#if wxUSE_ON_FATAL_EXCEPTION + Except_HandleCrash, +#endif // wxUSE_ON_FATAL_EXCEPTION +#ifdef __WXDEBUG__ + Except_ShowAssert, +#endif // __WXDEBUG__ Except_Dialog, Except_Quit = wxID_EXIT, @@ -154,12 +205,23 @@ 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_ThrowInt, MyFrame::OnThrowInt) EVT_MENU(Except_ThrowString, MyFrame::OnThrowString) + EVT_MENU(Except_ThrowObject, MyFrame::OnThrowObject) + EVT_MENU(Except_ThrowUnhandled, MyFrame::OnThrowUnhandled) + EVT_MENU(Except_Crash, MyFrame::OnCrash) +#if wxUSE_ON_FATAL_EXCEPTION + EVT_MENU(Except_HandleCrash, MyFrame::OnHandleCrash) +#endif // wxUSE_ON_FATAL_EXCEPTION +#ifdef __WXDEBUG__ + EVT_MENU(Except_ShowAssert, MyFrame::OnShowAssert) +#endif // __WXDEBUG__ END_EVENT_TABLE() BEGIN_EVENT_TABLE(MyDialog, wxDialog) EVT_BUTTON(Except_ThrowInt, MyDialog::OnThrowInt) EVT_BUTTON(Except_ThrowObject, MyDialog::OnThrowObject) + EVT_BUTTON(Except_Crash, MyDialog::OnCrash) END_EVENT_TABLE() // Create a new application object: this macro will allow wxWidgets to create @@ -176,9 +238,11 @@ IMPLEMENT_APP(MyApp) // 'Main program' equivalent: the program execution "starts" here bool MyApp::OnInit() { + if ( !wxApp::OnInit() ) + return false; + // create the main application window - MyFrame *frame = new MyFrame(_T("Except wxWidgets App"), - wxPoint(50, 50), wxSize(450, 340)); + MyFrame *frame = new MyFrame(); // and show it (the frames, unlike simple controls, are not shown when // created initially) @@ -190,44 +254,97 @@ bool MyApp::OnInit() return true; } -void -MyApp::HandleEvent(wxEvtHandler *handler, - wxEventFunction func, - wxEvent& event) const +bool MyApp::OnExceptionInMainLoop() { try { - wxApp::HandleEvent(handler, func, event); + throw; } catch ( int i ) { - wxLogError(_T("Caught an int %d in MyApp."), i); + wxLogWarning(_T("Caught an int %d in MyApp."), i); + } + catch ( MyException& e ) + { + wxLogWarning(_T("Caught MyException(%s) in MyApp."), e.what()); + } + catch ( ... ) + { + throw; } + + return true; } void MyApp::OnUnhandledException() { - wxMessageBox(_T("Unhandled exception caught, program will terminate."), + // this shows how we may let some exception propagate uncaught + try + { + throw; + } + catch ( UnhandledException& ) + { + throw; + } + catch ( ... ) + { + wxMessageBox(_T("Unhandled exception caught, program will terminate."), + _T("wxExcept Sample"), wxOK | wxICON_ERROR); + } +} + +void MyApp::OnFatalException() +{ + wxMessageBox(_T("Program has crashed and will terminate."), _T("wxExcept Sample"), wxOK | wxICON_ERROR); } +#ifdef __WXDEBUG__ + +void MyApp::OnAssert(const wxChar *file, + int line, + const wxChar *cond, + const wxChar *msg) +{ + // we don't have anything special to do here + wxApp::OnAssert(file, line, cond, msg); +} + +#endif // __WXDEBUG__ + // ============================================================================ // 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) +MyFrame::MyFrame() + : wxFrame(NULL, wxID_ANY, _T("Except wxWidgets App"), + wxPoint(50, 50), wxSize(450, 340)) { // set the frame icon - SetIcon(wxICON(mondrian)); + SetIcon(wxICON(sample)); #if wxUSE_MENUS // create a menu bar wxMenu *menuFile = new wxMenu; menuFile->Append(Except_Dialog, _T("Show &dialog\tCtrl-D")); + menuFile->AppendSeparator(); + menuFile->Append(Except_ThrowInt, _T("Throw an &int\tCtrl-I")); menuFile->Append(Except_ThrowString, _T("Throw a &string\tCtrl-S")); + menuFile->Append(Except_ThrowObject, _T("Throw an &object\tCtrl-O")); + menuFile->Append(Except_ThrowUnhandled, + _T("Throw &unhandled exception\tCtrl-U")); + menuFile->Append(Except_Crash, _T("&Crash\tCtrl-C")); + menuFile->AppendSeparator(); +#if wxUSE_ON_FATAL_EXCEPTION + menuFile->AppendCheckItem(Except_HandleCrash, _T("&Handle crashes\tCtrl-H")); menuFile->AppendSeparator(); +#endif // wxUSE_ON_FATAL_EXCEPTION +#ifdef __WXDEBUG__ + menuFile->Append(Except_ShowAssert, _T("Provoke &assert failure\tCtrl-A")); + menuFile->AppendSeparator(); +#endif // __WXDEBUG__ menuFile->Append(Except_Quit, _T("E&xit\tCtrl-Q"), _T("Quit this program")); wxMenu *helpMenu = new wxMenu; @@ -279,16 +396,58 @@ void MyFrame::OnDialog(wxCommandEvent& WXUNUSED(event)) } catch ( ... ) { + wxLogWarning(_T("An exception in MyDialog")); + Destroy(); throw; } } +void MyFrame::OnThrowInt(wxCommandEvent& WXUNUSED(event)) +{ + throw -17; +} + void MyFrame::OnThrowString(wxCommandEvent& WXUNUSED(event)) { - throw _T("some string"); + throw _T("string thrown from MyFrame"); +} + +void MyFrame::OnThrowObject(wxCommandEvent& WXUNUSED(event)) +{ + throw MyException(_T("Exception thrown from MyFrame")); +} + +void MyFrame::OnThrowUnhandled(wxCommandEvent& WXUNUSED(event)) +{ + throw UnhandledException(); +} + +void MyFrame::OnCrash(wxCommandEvent& WXUNUSED(event)) +{ + DoCrash(); } +#if wxUSE_ON_FATAL_EXCEPTION + +void MyFrame::OnHandleCrash(wxCommandEvent& event) +{ + wxHandleFatalExceptions(event.IsChecked()); +} + +#endif // wxUSE_ON_FATAL_EXCEPTION + +#ifdef __WXDEBUG__ + +void MyFrame::OnShowAssert(wxCommandEvent& WXUNUSED(event)) +{ + // provoke an assert from wxArrayString + wxArrayString arr; + arr[0]; +} + +#endif // __WXDEBUG__ + void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event)) { wxString msg; @@ -311,6 +470,8 @@ MyDialog::MyDialog(wxFrame *parent) 0, wxCENTRE | wxALL, 5); sizerTop->Add(new wxButton(this, Except_ThrowObject, _T("Throw &object")), 0, wxCENTRE | wxALL, 5); + sizerTop->Add(new wxButton(this, Except_Crash, _T("&Crash")), + 0, wxCENTRE | wxALL, 5); sizerTop->Add(new wxButton(this, wxID_CANCEL, _T("&Cancel")), 0, wxCENTRE | wxALL, 5); @@ -325,6 +486,11 @@ void MyDialog::OnThrowInt(wxCommandEvent& WXUNUSED(event)) void MyDialog::OnThrowObject(wxCommandEvent& WXUNUSED(event)) { - throw MyException(_T("Exception thrown from the dialog")); + throw MyException(_T("Exception thrown from MyDialog")); +} + +void MyDialog::OnCrash(wxCommandEvent& WXUNUSED(event)) +{ + DoCrash(); }