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git.saurik.com Git - wxWidgets.git/blob - interface/wx/app.h
1 /////////////////////////////////////////////////////////////////////////////
3 // Purpose: interface of wxApp
4 // Author: wxWidgets team
6 // Licence: wxWindows license
7 /////////////////////////////////////////////////////////////////////////////
13 This class is essential for writing console-only or hybrid apps without
14 having to define @c wxUSE_GUI=0.
17 @li set and get application-wide properties (see wxAppConsole::CreateTraits
18 and wxAppConsole::SetXXX functions)
19 @li implement the windowing system message or event loop: events in fact are
20 supported even in console-mode applications (see wxAppConsole::HandleEvent
21 and wxAppConsole::ProcessPendingEvents);
22 @li initiate application processing via wxApp::OnInit;
23 @li allow default processing of events not handled by other
24 objects in the application (see wxAppConsole::FilterEvent)
25 @li implement Apple-specific event handlers (see wxAppConsole::MacXXX functions)
27 You should use the macro IMPLEMENT_APP(appClass) in your application
28 implementation file to tell wxWidgets how to create an instance of your
31 Use DECLARE_APP(appClass) in a header file if you want the ::wxGetApp() function
32 (which returns a reference to your application object) to be visible to other
36 @category{appmanagement}
38 @see @ref overview_app, wxApp, wxAppTraits, wxEventLoopBase
40 class wxAppConsole
: public wxEvtHandler
44 Creates the wxAppTraits object when GetTraits() needs it for the first time.
48 virtual wxAppTraits
* CreateTraits();
55 virtual ~wxAppConsole();
64 Dispatches the next event in the windowing system event queue.
65 Blocks until an event appears if there are none currently
66 (use Pending() if this is not wanted).
68 This can be used for programming event loops, e.g.
75 @return @false if the event loop should stop and @true otherwise.
77 @see Pending(), wxEventLoopBase
79 virtual bool Dispatch();
82 Call this to explicitly exit the main message (event) loop.
83 You should normally exit the main loop (and the application) by deleting
86 virtual void ExitMainLoop();
89 This function is called before processing any event and allows the application
90 to preempt the processing of some events.
92 If this method returns -1 the event is processed normally, otherwise either
93 @true or @false should be returned and the event processing stops immediately
94 considering that the event had been already processed (for the former return
95 value) or that it is not going to be processed at all (for the latter one).
97 virtual int FilterEvent(wxEvent
& event
);
101 This function simply invokes the given method @a func of the specified
102 event handler @a handler with the @a event as parameter. It exists solely
103 to allow to catch the C++ exceptions which could be thrown by all event
104 handlers in the application in one place: if you want to do this, override
105 this function in your wxApp-derived class and add try/catch clause(s) to it.
107 virtual void HandleEvent(wxEvtHandler
* handler
,
108 wxEventFunction func
,
109 wxEvent
& event
) const;
112 Returns @true if called from inside Yield().
114 virtual bool IsYielding() const;
117 Process all pending events; it is necessary to call this function to
118 process posted events.
120 This happens during each event loop iteration in GUI mode but if there is
121 no main loop, it may be also called directly.
123 virtual void ProcessPendingEvents();
126 Called by wxWidgets on creation of the application. Override this if you wish
127 to provide your own (environment-dependent) main loop.
129 @return 0 under X, and the wParam of the WM_QUIT message under Windows.
131 virtual int MainLoop();
134 Returns @true if unprocessed events are in the window system event queue.
138 virtual bool Pending();
141 Yields control to pending messages in the windowing system.
143 This can be useful, for example, when a time-consuming process writes to a
144 text window. Without an occasional yield, the text window will not be updated
145 properly, and on systems with cooperative multitasking, such as Windows 3.1
146 other processes will not respond.
148 Caution should be exercised, however, since yielding may allow the
149 user to perform actions which are not compatible with the current task.
150 Disabling menu items or whole menus during processing can avoid unwanted
151 reentrance of code: see ::wxSafeYield for a better function.
152 You can avoid unwanted reentrancies also using IsYielding().
154 Note that Yield() will not flush the message logs. This is intentional as
155 calling Yield() is usually done to quickly update the screen and popping up
156 a message box dialog may be undesirable. If you do wish to flush the log
157 messages immediately (otherwise it will be done during the next idle loop
158 iteration), call wxLog::FlushActive.
160 Calling Yield() recursively is normally an error and an assert failure is
161 raised in debug build if such situation is detected. However if the
162 @a onlyIfNeeded parameter is @true, the method will just silently
163 return @false instead.
165 virtual bool Yield(bool onlyIfNeeded
= false);
171 Allows external code to modify global ::wxTheApp, but you should really
172 know what you're doing if you call it.
175 Replacement for the global application object.
179 static void SetInstance(wxAppConsole
* app
);
182 Returns the one and only global application object.
183 Usually wxTheApp is used instead.
187 static wxAppConsole
* GetInstance();
190 Returns @true if the main event loop is currently running, i.e. if the
191 application is inside OnRun().
193 This can be useful to test whether events can be dispatched. For example,
194 if this function returns @false, non-blocking sockets cannot be used because
195 the events from them would never be processed.
197 static bool IsMainLoopRunning();
201 @name Mac-specific functions
206 Called in response of an "open-application" Apple event.
207 Override this to create a new document in your app.
211 virtual void MacNewFile();
214 Called in response of an "open-document" Apple event.
216 You need to override this method in order to open a document file after the
217 user double clicked on it or if the document file was dropped on either the
218 running application or the application icon in Finder.
222 virtual void MacOpenFile(const wxString
& fileName
);
225 Called in response of a "get-url" Apple event.
229 virtual void MacOpenURL(const wxString
& url
);
232 Called in response of a "print-document" Apple event.
236 virtual void MacPrintFile(const wxString
& fileName
);
239 Called in response of a "reopen-application" Apple event.
243 virtual void MacReopenApp();
249 @name Callbacks for application-wide "events"
254 This function is called when an assert failure occurs, i.e. the condition
255 specified in wxASSERT() macro evaluated to @false.
257 It is only called in debug mode (when @c __WXDEBUG__ is defined) as
258 asserts are not left in the release code at all.
259 The base class version shows the default assert failure dialog box proposing to
260 the user to stop the program, continue or ignore all subsequent asserts.
263 the name of the source file where the assert occurred
265 the line number in this file where the assert occurred
267 the name of the function where the assert occurred, may be
268 empty if the compiler doesn't support C99 __FUNCTION__
270 the condition of the failed assert in text form
272 the message specified as argument to wxASSERT_MSG or wxFAIL_MSG, will
273 be @NULL if just wxASSERT or wxFAIL was used
275 virtual void OnAssertFailure(const wxChar
*file
,
282 Called when command line parsing fails (i.e. an incorrect command line option
283 was specified by the user). The default behaviour is to show the program usage
284 text and abort the program.
286 Return @true to continue normal execution or @false to return
287 @false from OnInit() thus terminating the program.
291 virtual bool OnCmdLineError(wxCmdLineParser
& parser
);
294 Called when the help option (@c --help) was specified on the command line.
295 The default behaviour is to show the program usage text and abort the program.
297 Return @true to continue normal execution or @false to return
298 @false from OnInit() thus terminating the program.
302 virtual bool OnCmdLineHelp(wxCmdLineParser
& parser
);
305 Called after the command line had been successfully parsed. You may override
306 this method to test for the values of the various parameters which could be
307 set from the command line.
309 Don't forget to call the base class version unless you want to suppress
310 processing of the standard command line options.
311 Return @true to continue normal execution or @false to return @false from
312 OnInit() thus terminating the program.
316 virtual bool OnCmdLineParsed(wxCmdLineParser
& parser
);
319 This function is called if an unhandled exception occurs inside the main
320 application event loop. It can return @true to ignore the exception and to
321 continue running the loop or @false to exit the loop and terminate the
322 program. In the latter case it can also use C++ @c throw keyword to
323 rethrow the current exception.
325 The default behaviour of this function is the latter in all ports except under
326 Windows where a dialog is shown to the user which allows him to choose between
327 the different options. You may override this function in your class to do
328 something more appropriate.
330 Finally note that if the exception is rethrown from here, it can be caught in
331 OnUnhandledException().
333 virtual bool OnExceptionInMainLoop();
336 Override this member function for any processing which needs to be
337 done as the application is about to exit. OnExit is called after
338 destroying all application windows and controls, but before
339 wxWidgets cleanup. Note that it is not called at all if
342 The return value of this function is currently ignored, return the same
343 value as returned by the base class method if you override it.
345 virtual int OnExit();
348 This function may be called if something fatal happens: an unhandled
349 exception under Win32 or a a fatal signal under Unix, for example. However,
350 this will not happen by default: you have to explicitly call
351 wxHandleFatalExceptions() to enable this.
353 Generally speaking, this function should only show a message to the user and
354 return. You may attempt to save unsaved data but this is not guaranteed to
355 work and, in fact, probably won't.
357 @see wxHandleFatalExceptions()
359 virtual void OnFatalException();
362 This must be provided by the application, and will usually create the
363 application's main window, optionally calling SetTopWindow().
365 You may use OnExit() to clean up anything initialized here, provided
366 that the function returns @true.
368 Notice that if you want to to use the command line processing provided by
369 wxWidgets you have to call the base class version in the derived class
372 Return @true to continue processing, @false to exit the application
375 virtual bool OnInit();
378 Called from OnInit() and may be used to initialize the parser with the
379 command line options for this application. The base class versions adds
380 support for a few standard options only.
382 virtual void OnInitCmdLine(wxCmdLineParser
& parser
);
385 This virtual function is where the execution of a program written in wxWidgets
386 starts. The default implementation just enters the main loop and starts
387 handling the events until it terminates, either because ExitMainLoop() has
388 been explicitly called or because the last frame has been deleted and
389 GetExitOnFrameDelete() flag is @true (this is the default).
391 The return value of this function becomes the exit code of the program, so it
392 should return 0 in case of successful termination.
397 This function is called when an unhandled C++ exception occurs inside
398 OnRun() (the exceptions which occur during the program startup and shutdown
399 might not be caught at all). Notice that by now the main event loop has been
400 terminated and the program will exit, if you want to prevent this from happening
401 (i.e. continue running after catching an exception) you need to override
402 OnExceptionInMainLoop().
404 The default implementation shows information about the exception in debug build
405 but does nothing in the release build.
407 virtual void OnUnhandledException();
413 @name Application informations
418 Returns the user-readable application name.
420 The difference between this string and the one returned by GetAppName()
421 is that this one is meant to be shown to the user and so should be used
422 for the window titles, page headers and so on while the other one
423 should be only used internally, e.g. for the file names or
424 configuration file keys. By default, returns the application name as
425 returned by GetAppName() capitalized using wxString::Capitalize().
429 wxString
GetAppDisplayName() const;
432 Returns the application name.
434 @remarks wxWidgets sets this to a reasonable default before calling
435 OnInit(), but the application can reset it at will.
437 @see GetAppDisplayName()
439 wxString
GetAppName() const;
442 Gets the class name of the application. The class name may be used in a
443 platform specific manner to refer to the application.
447 wxString
GetClassName() const;
450 Returns a pointer to the wxAppTraits object for the application.
451 If you want to customize the wxAppTraits object, you must override the
452 CreateTraits() function.
454 wxAppTraits
* GetTraits();
457 Returns the user-readable vendor name. The difference between this string
458 and the one returned by GetVendorName() is that this one is meant to be shown
459 to the user and so should be used for the window titles, page headers and so on
460 while the other one should be only used internally, e.g. for the file names or
461 configuration file keys.
463 By default, returns the same string as GetVendorName().
467 const wxString
& GetVendorDisplayName() const;
470 Returns the application's vendor name.
472 const wxString
& GetVendorName() const;
475 Set the application name to be used in the user-visible places such as
478 See GetAppDisplayName() for more about the differences between the
479 display name and name.
481 Notice that if this function is called, the name is used as is, without
482 any capitalization as done by default by GetAppDisplayName().
484 void SetAppDisplayName(const wxString
& name
);
487 Sets the name of the application. This name should be used for file names,
488 configuration file entries and other internal strings. For the user-visible
489 strings, such as the window titles, the application display name set by
490 SetAppDisplayName() is used instead.
492 By default the application name is set to the name of its executable file.
496 void SetAppName(const wxString
& name
);
499 Sets the class name of the application. This may be used in a platform specific
500 manner to refer to the application.
504 void SetClassName(const wxString
& name
);
507 Set the vendor name to be used in the user-visible places.
508 See GetVendorDisplayName() for more about the differences between the
509 display name and name.
511 void SetVendorDisplayName(const wxString
& name
);
514 Sets the name of application's vendor. The name will be used
515 in registry access. A default name is set by wxWidgets.
519 void SetVendorName(const wxString
& name
);
525 Number of command line arguments (after environment-specific processing).
530 Command line arguments (after environment-specific processing).
532 Under Windows and Linux/Unix, you should parse the command line
533 arguments and check for files to be opened when starting your
534 application. Under OS X, you need to override MacOpenFile()
535 since command line arguments are used differently there.
537 You may use the wxCmdLineParser to parse command line arguments.
548 The wxApp class represents the application itself when @c wxUSE_GUI=1.
550 In addition to the features provided by wxAppConsole it keeps track of
551 the <em>top window</em> (see SetTopWindow()) and adds support for
552 video modes (see SetVideoMode()).
554 In general, application-wide settings for GUI-only apps are accessible
555 from wxApp (or from wxSystemSettings or wxSystemOptions classes).
558 @category{appmanagement}
560 @see @ref overview_app, wxAppTraits, wxEventLoopBase, wxSystemSettings
562 class wxApp
: public wxAppConsole
566 Constructor. Called implicitly with a definition of a wxApp object.
571 Destructor. Will be called implicitly on program exit if the wxApp
572 object is created on the stack.
577 Get display mode that is used use. This is only used in framebuffer
578 wxWin ports (such as wxMGL or wxDFB).
580 virtual wxVideoMode
GetDisplayMode() const;
583 Returns @true if the application will exit when the top-level frame is deleted.
585 @see SetExitOnFrameDelete()
587 bool GetExitOnFrameDelete() const;
590 Return the layout direction for the current locale or @c wxLayout_Default
593 virtual wxLayoutDirection
GetLayoutDirection() const;
596 Returns @true if the application will use the best visual on systems that support
597 different visuals, @false otherwise.
599 @see SetUseBestVisual()
601 bool GetUseBestVisual() const;
604 Returns a pointer to the top window.
607 If the top window hasn't been set using SetTopWindow(), this function
608 will find the first top-level window (frame or dialog or instance of
609 wxTopLevelWindow) from the internal top level window list and return that.
613 virtual wxWindow
* GetTopWindow() const;
616 Returns @true if the application is active, i.e. if one of its windows is
617 currently in the foreground.
619 If this function returns @false and you need to attract users attention to
620 the application, you may use wxTopLevelWindow::RequestUserAttention to do it.
622 virtual bool IsActive() const;
625 Windows-only function for processing a message. This function is called
626 from the main message loop, checking for windows that may wish to process it.
628 The function returns @true if the message was processed, @false otherwise.
629 If you use wxWidgets with another class library with its own message loop,
630 you should make sure that this function is called to allow wxWidgets to
631 receive messages. For example, to allow co-existence with the Microsoft
632 Foundation Classes, override the PreTranslateMessage function:
635 // Provide wxWidgets message loop compatibility
636 BOOL CTheApp::PreTranslateMessage(MSG *msg)
638 if (wxTheApp && wxTheApp->ProcessMessage((WXMSW *)msg))
641 return CWinApp::PreTranslateMessage(msg);
647 bool ProcessMessage(WXMSG
* msg
);
650 Sends idle events to a window and its children.
651 Please note that this function is internal to wxWidgets and shouldn't be used
654 @remarks These functions poll the top-level windows, and their children,
655 for idle event processing. If @true is returned, more OnIdle
656 processing is requested by one or more window.
660 virtual bool SendIdleEvents(wxWindow
* win
, wxIdleEvent
& event
);
663 Set display mode to use. This is only used in framebuffer wxWin
664 ports (such as wxMGL or wxDFB). This method should be called from
667 virtual bool SetDisplayMode(const wxVideoMode
& info
);
670 Allows the programmer to specify whether the application will exit when the
671 top-level frame is deleted.
674 If @true (the default), the application will exit when the top-level frame
675 is deleted. If @false, the application will continue to run.
677 @see GetExitOnFrameDelete(), @ref overview_app_shutdown
679 void SetExitOnFrameDelete(bool flag
);
682 Allows runtime switching of the UI environment theme.
684 Currently implemented for wxGTK2-only.
685 Return @true if theme was successfully changed.
688 The name of the new theme or an absolute path to a gtkrc-theme-file
690 virtual bool SetNativeTheme(const wxString
& theme
);
693 Sets the 'top' window. You can call this from within OnInit() to let wxWidgets
694 know which is the main window. You don't have to set the top window;
695 it is only a convenience so that (for example) certain dialogs without parents
696 can use a specific window as the top window.
698 If no top window is specified by the application, wxWidgets just uses the
699 first frame or dialog (or better, any wxTopLevelWindow) in its top-level
700 window list, when it needs to use the top window.
701 If you previously called SetTopWindow() and now you need to restore this
702 automatic behaviour you can call @code wxApp::SetTopWindow(NULL) @endcode.
707 @see GetTopWindow(), OnInit()
709 void SetTopWindow(wxWindow
* window
);
712 Allows the programmer to specify whether the application will use the best
713 visual on systems that support several visual on the same display. This is typically
714 the case under Solaris and IRIX, where the default visual is only 8-bit whereas
715 certain applications are supposed to run in TrueColour mode.
717 Note that this function has to be called in the constructor of the wxApp
718 instance and won't have any effect when called later on.
719 This function currently only has effect under GTK.
722 If @true, the app will use the best visual.
723 @param forceTrueColour
724 If @true then the application will try to force using a TrueColour
725 visual and abort the app if none is found.
727 void SetUseBestVisual(bool flag
, bool forceTrueColour
= false);
732 // ============================================================================
733 // Global functions/macros
734 // ============================================================================
737 /** @addtogroup group_funcmacro_rtti */
741 This is used in headers to create a forward declaration of the ::wxGetApp()
742 function implemented by IMPLEMENT_APP().
744 It creates the declaration <tt>className& wxGetApp()</tt>.
754 #define DECLARE_APP( className )
757 This is used in the application class implementation file to make the
758 application class known to wxWidgets for dynamic construction.
770 #define IMPLEMENT_APP( className )
777 The global pointer to the singleton wxApp object.
779 @see wxApp::GetInstance()
785 /** @addtogroup group_funcmacro_appinitterm */
789 This function doesn't exist in wxWidgets but it is created by using the
790 IMPLEMENT_APP() macro.
792 Thus, before using it anywhere but in the same module where this macro is
793 used, you must make it available using DECLARE_APP().
795 The advantage of using this function compared to directly using the global
796 ::wxTheApp pointer is that the latter is of type wxApp* and so wouldn't
797 allow you to access the functions specific to your application class but
798 not present in wxApp while wxGetApp() returns the object of the right type.
802 wxAppDerivedClass
& wxGetApp();
805 If @a doIt is @true, the fatal exceptions (also known as general protection
806 faults under Windows or segmentation violations in the Unix world) will be
807 caught and passed to wxApp::OnFatalException.
809 By default, i.e. before this function is called, they will be handled in
810 the normal way which usually just means that the application will be
811 terminated. Calling wxHandleFatalExceptions() with @a doIt equal to @false
812 will restore this default behaviour.
814 Notice that this function is only available if @c wxUSE_ON_FATAL_EXCEPTION
815 is 1 and under Windows platform this requires a compiler with support for
816 SEH (structured exception handling) which currently means only Microsoft
817 Visual C++ or a recent Borland C++ version.
821 bool wxHandleFatalExceptions(bool doIt
= true);
824 This function is used in wxBase only and only if you don't create
825 wxApp object at all. In this case you must call it from your
826 @c main() function before calling any other wxWidgets functions.
828 If the function returns @false the initialization could not be performed,
829 in this case the library cannot be used and wxUninitialize() shouldn't be
832 This function may be called several times but wxUninitialize() must be
833 called for each successful call to this function.
840 This function is for use in console (wxBase) programs only. It must be called
841 once for each previous successful call to wxInitialize().
845 void wxUninitialize();
848 This function wakes up the (internal and platform dependent) idle system,
849 i.e. it will force the system to send an idle event even if the system
850 currently @e is idle and thus would not send any idle event until after
851 some other event would get sent. This is also useful for sending events
852 between two threads and is used by the corresponding functions
853 wxPostEvent() and wxEvtHandler::AddPendingEvent().
863 This function is kept only for backwards compatibility. Please use
864 the wxApp::Yield method instead in any new code.
871 This function is similar to wxYield(), except that it disables the user
872 input to all program windows before calling wxYield() and re-enables it
873 again afterwards. If @a win is not @NULL, this window will remain enabled,
874 allowing the implementation of some limited user interaction.
875 Returns the result of the call to ::wxYield.
879 bool wxSafeYield(wxWindow
* win
= NULL
, bool onlyIfNeeded
= false);
882 This function initializes wxWidgets in a platform-dependent way. Use this if you
883 are not using the default wxWidgets entry code (e.g. main or WinMain).
885 For example, you can initialize wxWidgets from an Microsoft Foundation Classes
886 (MFC) application using this function.
888 @note This overload of wxEntry is available under all platforms.
894 int wxEntry(int& argc
, wxChar
** argv
);
897 See wxEntry(int&,wxChar**) for more info about this function.
899 Notice that under Windows CE platform, and only there, the type of @a pCmdLine
900 is @c wchar_t *, otherwise it is @c char *, even in Unicode build.
902 @remarks To clean up wxWidgets, call wxApp::OnExit followed by the static
903 function wxApp::CleanUp. For example, if exiting from an MFC application
904 that also uses wxWidgets:
906 int CTheApp::ExitInstance()
908 // OnExit isn't called by CleanUp so must be called explicitly.
912 return CWinApp::ExitInstance();
918 int wxEntry(HINSTANCE hInstance
,
919 HINSTANCE hPrevInstance
= NULL
,
920 char* pCmdLine
= NULL
,
921 int nCmdShow
= SW_SHOWNORMAL
);
927 /** @addtogroup group_funcmacro_procctrl */
931 Exits application after calling wxApp::OnExit.
933 Should only be used in an emergency: normally the top-level frame
934 should be deleted (after deleting all other frames) to terminate the
935 application. See wxCloseEvent and wxApp.