use wxDC::GetMultiLineTextExtent() instead of duplicating its code in wxButton::DoGet...

[wxWidgets.git] / samples / except / except.cpp

diff --git a/samples/except/except.cpp b/samples/except/except.cpp
index a7f2d7ad94c15bca0b739cfa5d66696d59bf0e39..7d1c9991eb8f511af40d24194840243f28a0d6a4 100644 (file)
--- a/samples/except/except.cpp
+++ b/samples/except/except.cpp
@@ -1,11 +1,11 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        except.cpp
-// Purpose:     Except wxWindows sample
-// Author:      Julian Smart
+// Name:        samples/except/except.cpp
+// Purpose:     shows how C++ exceptions can be used in wxWidgets
+// Author:      Vadim Zeitlin

 // Modified by:
 // Modified by:

-// Created:     04/01/98
+// Created:     2003-09-17

 // RCS-ID:      $Id$
 // RCS-ID:      $Id$

-// Copyright:   (c) Julian Smart
+// Copyright:   (c) 2003-2005 Vadim Zeitlin

 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 


@@ -24,8 +24,12 @@
     #pragma hdrstop
 #endif
 
     #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
 // for all others, include the necessary headers (this file is usually all you

-// need because it includes almost all "standard" wxWindows headers)
+// need because it includes almost all "standard" wxWidgets headers)

 #ifndef WX_PRECOMP
     #include "wx/log.h"
 
 #ifndef WX_PRECOMP
     #include "wx/log.h"
 


@@ -37,7 +41,9 @@
     #include "wx/button.h"
     #include "wx/sizer.h"
 
     #include "wx/button.h"
     #include "wx/sizer.h"
 

-    #include "wx/utils.h"               // for wxMessageBox
+    #include "wx/utils.h"
+    #include "wx/msgdlg.h"
+    #include "wx/icon.h"

 #endif
 
 // ----------------------------------------------------------------------------
 #endif
 
 // ----------------------------------------------------------------------------


@@ -49,6 +55,16 @@
     #include "../sample.xpm"
 #endif
 
     #include "../sample.xpm"
 #endif
 

+// ----------------------------------------------------------------------------
+// private functions
+// ----------------------------------------------------------------------------
+
+static void DoCrash()
+{
+    char *p = 0;
+    strcpy(p, "Let's crash");
+}
+

 // ----------------------------------------------------------------------------
 // private classes
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // private classes
 // ----------------------------------------------------------------------------


@@ -65,13 +81,15 @@ public:
 
     // 2nd-level exception handling: we get all the exceptions occuring in any
     // event handler here
 
     // 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;
+    virtual bool OnExceptionInMainLoop();

 
     // 3rd, and final, level exception handling: whenever an unhandled
     // exception is caught, this function is called
     virtual void OnUnhandledException();
 
     // 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();

 };
 
 // Define a new frame type: this is going to be our main frame
 };
 
 // Define a new frame type: this is going to be our main frame


@@ -79,21 +97,27 @@ class MyFrame : public wxFrame
 {
 public:
     // ctor(s)
 {
 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);
 
     // 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 OnThrowString(wxCommandEvent& event);

+    void OnThrowObject(wxCommandEvent& event);
+    void OnThrowUnhandled(wxCommandEvent& event);
+
+    void OnCrash(wxCommandEvent& event);
+    void OnHandleCrash(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:
 
     // 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 wxWindows events must use this macro
+    // any class wishing to process wxWidgets events must use this macro

     DECLARE_EVENT_TABLE()
 };
 
     DECLARE_EVENT_TABLE()
 };
 


@@ -106,6 +130,7 @@ public:
     // event handlers
     void OnThrowInt(wxCommandEvent& event);
     void OnThrowObject(wxCommandEvent& event);
     // event handlers
     void OnThrowInt(wxCommandEvent& event);
     void OnThrowObject(wxCommandEvent& event);

+    void OnCrash(wxCommandEvent& event);

 
 private:
     DECLARE_EVENT_TABLE()
 
 private:
     DECLARE_EVENT_TABLE()


@@ -123,6 +148,11 @@ private:
     wxString m_msg;
 };
 
     wxString m_msg;
 };
 

+// Another exception class which just has to be different from anything else
+class UnhandledException
+{
+};
+

 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------


@@ -130,12 +160,13 @@ private:
 // IDs for the controls and the menu commands
 enum
 {
 // IDs for the controls and the menu commands
 enum
 {

-    // control ids
+    // control ids and menu items

     Except_ThrowInt = 100,
     Except_ThrowInt = 100,

+    Except_ThrowString,

     Except_ThrowObject,
     Except_ThrowObject,

-
-    // menu items
-    Except_ThrowString = 200,
+    Except_ThrowUnhandled,
+    Except_Crash,
+    Except_HandleCrash,

     Except_Dialog,
 
     Except_Quit = wxID_EXIT,
     Except_Dialog,
 
     Except_Quit = wxID_EXIT,


@@ -143,25 +174,31 @@ enum
 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------

-// event tables and other macros for wxWindows
+// event tables and other macros for wxWidgets

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-// the event tables connect the wxWindows events with the functions (event
+// 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)
 // 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_ThrowInt, MyFrame::OnThrowInt)

     EVT_MENU(Except_ThrowString, MyFrame::OnThrowString)
     EVT_MENU(Except_ThrowString, MyFrame::OnThrowString)

+    EVT_MENU(Except_ThrowObject, MyFrame::OnThrowObject)
+    EVT_MENU(Except_ThrowUnhandled, MyFrame::OnThrowUnhandled)
+    EVT_MENU(Except_Crash, MyFrame::OnCrash)
+    EVT_MENU(Except_HandleCrash, MyFrame::OnHandleCrash)

 END_EVENT_TABLE()
 
 BEGIN_EVENT_TABLE(MyDialog, wxDialog)
     EVT_BUTTON(Except_ThrowInt, MyDialog::OnThrowInt)
     EVT_BUTTON(Except_ThrowObject, MyDialog::OnThrowObject)
 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()
 
 END_EVENT_TABLE()
 

-// Create a new application object: this macro will allow wxWindows to create
+// 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
 // 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


@@ -176,8 +213,7 @@ IMPLEMENT_APP(MyApp)
 bool MyApp::OnInit()
 {
     // create the main application window
 bool MyApp::OnInit()
 {
     // create the main application window

-    MyFrame *frame = new MyFrame(_T("Except wxWindows 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)
 
     // and show it (the frames, unlike simple controls, are not shown when
     // created initially)


@@ -189,24 +225,49 @@ bool MyApp::OnInit()
     return true;
 }
 
     return true;
 }
 

-void
-MyApp::HandleEvent(wxEvtHandler *handler,
-                   wxEventFunction func,
-                   wxEvent& event) const
+bool MyApp::OnExceptionInMainLoop()

 {
     try
     {
 {
     try
     {

-        wxApp::HandleEvent(handler, func, event);
+        throw;

     }
     catch ( int i )
     {
     }
     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()
 {
 }
 
 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);
 }
 
                  _T("wxExcept Sample"), wxOK | wxICON_ERROR);
 }
 


@@ -215,17 +276,26 @@ void MyApp::OnUnhandledException()
 // ============================================================================
 
 // frame constructor
 // ============================================================================
 
 // frame constructor

-MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size, long style)
-       : wxFrame(NULL, -1, title, pos, size, style)
+MyFrame::MyFrame()
+       : wxFrame(NULL, wxID_ANY, _T("Except wxWidgets App"),
+                 wxPoint(50, 50), wxSize(450, 340))

 {
     // set the frame icon
 {
     // 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"));
 
 #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_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();
+    menuFile->AppendCheckItem(Except_HandleCrash, _T("&Handle crashes\tCtrl-H"));

     menuFile->AppendSeparator();
     menuFile->Append(Except_Quit, _T("E&xit\tCtrl-Q"), _T("Quit this program"));
 
     menuFile->AppendSeparator();
     menuFile->Append(Except_Quit, _T("E&xit\tCtrl-Q"), _T("Quit this program"));
 


@@ -244,7 +314,7 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size,
 #if wxUSE_STATUSBAR && !defined(__WXWINCE__)
     // create a status bar just for fun (by default with 1 pane only)
     CreateStatusBar(2);
 #if wxUSE_STATUSBAR && !defined(__WXWINCE__)
     // create a status bar just for fun (by default with 1 pane only)
     CreateStatusBar(2);

-    SetStatusText(_T("Welcome to wxWindows!"));
+    SetStatusText(_T("Welcome to wxWidgets!"));

 #endif // wxUSE_STATUSBAR
 }
 
 #endif // wxUSE_STATUSBAR
 }
 


@@ -278,14 +348,41 @@ void MyFrame::OnDialog(wxCommandEvent& WXUNUSED(event))
     }
     catch ( ... )
     {
     }
     catch ( ... )
     {

+        wxLogWarning(_T("An exception in MyDialog"));
+

         Destroy();
         throw;
     }
 }
 
         Destroy();
         throw;
     }
 }
 

+void MyFrame::OnThrowInt(wxCommandEvent& WXUNUSED(event))
+{
+    throw -17;
+}
+

 void MyFrame::OnThrowString(wxCommandEvent& WXUNUSED(event))
 {
 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();
+}
+
+void MyFrame::OnHandleCrash(wxCommandEvent& event)
+{
+    wxHandleFatalExceptions(event.IsChecked());

 }
 
 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 }
 
 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))


@@ -302,7 +399,7 @@ void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 // ============================================================================
 
 MyDialog::MyDialog(wxFrame *parent)
 // ============================================================================
 
 MyDialog::MyDialog(wxFrame *parent)

-        : wxDialog(parent, -1, wxString(_T("Throw exception dialog")))
+        : wxDialog(parent, wxID_ANY, wxString(_T("Throw exception dialog")))

 {
     wxSizer *sizerTop = new wxBoxSizer(wxVERTICAL);
 
 {
     wxSizer *sizerTop = new wxBoxSizer(wxVERTICAL);
 


@@ -310,6 +407,8 @@ MyDialog::MyDialog(wxFrame *parent)
                   0, wxCENTRE | wxALL, 5);
     sizerTop->Add(new wxButton(this, Except_ThrowObject, _T("Throw &object")),
                   0, wxCENTRE | wxALL, 5);
                   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);
 
     sizerTop->Add(new wxButton(this, wxID_CANCEL, _T("&Cancel")),
                   0, wxCENTRE | wxALL, 5);
 


@@ -324,6 +423,11 @@ void MyDialog::OnThrowInt(wxCommandEvent& WXUNUSED(event))
 
 void MyDialog::OnThrowObject(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();

 }
 
 }