interface/app.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        app.h
   3 // Purpose:     documentation for wxApp class
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxApp
  11     @wxheader{app.h}
  12
  13     The @b wxApp class represents the application itself. It is used
  14     to:
  15
  16      set and get application-wide properties;
  17      implement the windowing system message or event loop;
  18      initiate application processing via wxApp::OnInit;
  19      allow default processing of events not handled by other
  20     objects in the application.
  21
  22     You should use the macro IMPLEMENT_APP(appClass) in your application
  23     implementation
  24     file to tell wxWidgets how to create an instance of your application class.
  25
  26     Use DECLARE_APP(appClass) in a header file if you want the wxGetApp function
  27     (which returns
  28     a reference to your application object) to be visible to other files.
  29
  30     @library{wxbase}
  31     @category{appmanagement}
  32
  33     @seealso
  34     @ref overview_wxappoverview "wxApp overview"
  35 */
  36 class wxApp : public wxEvtHandler
  37 {
  38 public:
  39     /**
  40         Constructor. Called implicitly with a definition of a wxApp object.
  41     */
  42     wxApp();
  43
  44     /**
  45         Destructor. Will be called implicitly on program exit if the wxApp
  46         object is created on the stack.
  47     */
  48     ~wxApp();
  49
  50     /**
  51         Creates a wxLog class for the application to use for logging errors. The default
  52         implementation returns a new wxLogGui class.
  53
  54         @see wxLog
  55     */
  56     virtual wxLog* CreateLogTarget();
  57
  58     /**
  59         Creates the wxAppTraits object when GetTraits()
  60         needs it for the first time.
  61
  62         @see wxAppTraits
  63     */
  64     virtual wxAppTraits* CreateTraits();
  65
  66     /**
  67         Dispatches the next event in the windowing system event queue.
  68         This can be used for programming event loops, e.g.
  69
  70         @see Pending()
  71     */
  72     virtual void Dispatch();
  73
  74     /**
  75         Call this to explicitly exit the main message (event) loop.
  76         You should normally exit the main loop (and the application) by deleting
  77         the top window.
  78     */
  79     virtual void ExitMainLoop();
  80
  81     /**
  82         This function is called before processing any event and allows the application
  83         to preempt the processing of some events. If this method returns -1 the event
  84         is processed normally, otherwise either @true or @false should be
  85         returned and the event processing stops immediately considering that the event
  86         had been already processed (for the former return value) or that it is not
  87         going to be processed at all (for the latter one).
  88     */
  89     int FilterEvent(wxEvent& event);
  90
  91     /**
  92         Returns the user-readable application name. The difference between this string
  93         and the one returned by GetAppName() is that this one
  94         is meant to be shown to the user and so should be used for the window titles,
  95         page headers and so on while the other one should be only used internally, e.g.
  96         for the file names or configuration file keys.
  97         By default, returns the same string as GetAppName().
  98         This function is new since wxWidgets version 2.9.0
  99     */
 100     wxString GetAppDisplayName();
 101
 102     /**
 103         Returns the application name.
 104
 105         @remarks wxWidgets sets this to a reasonable default before calling
 106                  OnInit(), but the application can reset it at will.
 107
 108         @see GetAppDisplayName()
 109     */
 110     wxString GetAppName();
 111
 112     /**
 113         Gets the class name of the application. The class name may be used in a
 114         platform specific
 115         manner to refer to the application.
 116
 117         @see SetClassName()
 118     */
 119     wxString GetClassName();
 120
 121     /**
 122         Returns @true if the application will exit when the top-level window is deleted,
 123         @false
 124         otherwise.
 125
 126         @see SetExitOnFrameDelete(), @ref overview_wxappshutdownoverview "wxApp
 127              shutdown overview"
 128     */
 129     bool GetExitOnFrameDelete();
 130
 131     /**
 132         Returns the one and only global application object.
 133         Usually @c wxTheApp is usead instead.
 134
 135         @see SetInstance()
 136     */
 137     static wxAppConsole* GetInstance();
 138
 139     /**
 140         Returns a pointer to the top window.
 141
 142         @remarks If the top window hasn't been set using SetTopWindow(),
 143                  this function will find the first top-level window
 144                  (frame or dialog) and return that.
 145
 146         @see SetTopWindow()
 147     */
 148     virtual wxWindow* GetTopWindow();
 149
 150     /**
 151         Returns a pointer to the wxAppTraits object for the application.
 152         If you want to customize the wxAppTraits object, you must override the
 153         CreateTraits() function.
 154     */
 155     wxAppTraits* GetTraits();
 156
 157     /**
 158         Returns @true if the application will use the best visual on systems that support
 159         different visuals, @false otherwise.
 160
 161         @see SetUseBestVisual()
 162     */
 163     bool GetUseBestVisual();
 164
 165     /**
 166         Returns the user-readable vendor name. The difference between this string
 167         and the one returned by GetVendorName() is that this one
 168         is meant to be shown to the user and so should be used for the window titles,
 169         page headers and so on while the other one should be only used internally, e.g.
 170         for the file names or configuration file keys.
 171         By default, returns the same string as GetVendorName().
 172         This function is new since wxWidgets version 2.9.0
 173     */
 174     wxString GetVendorDisplayName();
 175
 176     /**
 177         Returns the application's vendor name.
 178     */
 179     wxString GetVendorName();
 180
 181     /**
 182         This function simply invokes the given method @a func of the specified
 183         event handler @a handler with the @a event as parameter. It exists solely
 184         to allow to catch the C++ exceptions which could be thrown by all event
 185         handlers in the application in one place: if you want to do this, override this
 186         function in your wxApp-derived class and add try/catch clause(s) to it.
 187     */
 188     virtual void HandleEvent(wxEvtHandler handler,
 189                              wxEventFunction func,
 190                              wxEvent& event);
 191
 192     /**
 193         Returns @true if the application is active, i.e. if one of its windows is
 194         currently in the foreground. If this function returns @false and you need to
 195         attract users attention to the application, you may use
 196         wxTopLevelWindow::RequestUserAttention
 197         to do it.
 198     */
 199     bool IsActive();
 200
 201     /**
 202         Returns @true if the main event loop is currently running, i.e. if the
 203         application is inside OnRun().
 204         This can be useful to test whether events can be dispatched. For example,
 205         if this function returns @false, non-blocking sockets cannot be used because
 206         the events from them would never be processed.
 207     */
 208     static bool IsMainLoopRunning();
 209
 210     /**
 211         Mac specific. Called in response of an "open-application" Apple event.
 212         Override this to create a new document in your app.
 213     */
 214     void MacNewFile();
 215
 216     /**
 217         Mac specific. Called in response of an "open-document" Apple event. You need to
 218         override this method in order to open a document file after the
 219         user double clicked on it or if the document file was dropped
 220         on either the running application or the application icon in
 221         Finder.
 222     */
 223     void MacOpenFile(const wxString& fileName);
 224
 225     /**
 226         Mac specific. Called in response of a "get-url" Apple event.
 227     */
 228     void MacOpenURL(const wxString& url);
 229
 230     /**
 231         Mac specific. Called in response of a "print-document" Apple event.
 232     */
 233     void MacPrintFile(const wxString& fileName);
 234
 235     /**
 236         Mac specific. Called in response of a "reopen-application" Apple event.
 237     */
 238     void MacReopenApp();
 239
 240     /**
 241         Called by wxWidgets on creation of the application. Override this if you wish
 242         to provide your own (environment-dependent) main loop.
 243
 244         @returns Returns 0 under X, and the wParam of the WM_QUIT message under
 245                  Windows.
 246     */
 247     virtual int MainLoop();
 248
 249     /**
 250         This function is called when an assert failure occurs, i.e. the condition
 251         specified in wxASSERT macro evaluated to @false.
 252         It is only called in debug mode (when @c __WXDEBUG__ is defined) as
 253         asserts are not left in the release code at all.
 254         The base class version shows the default assert failure dialog box proposing to
 255         the user to stop the program, continue or ignore all subsequent asserts.
 256
 257         @param file
 258             the name of the source file where the assert occurred
 259         @param line
 260             the line number in this file where the assert occurred
 261         @param func
 262             the name of the function where the assert occurred, may be
 263             empty if the compiler doesn't support C99 __FUNCTION__
 264         @param cond
 265             the condition of the failed assert in text form
 266         @param msg
 267             the message specified as argument to
 268             wxASSERT_MSG or wxFAIL_MSG, will
 269             be @NULL if just wxASSERT or wxFAIL
 270             was used
 271     */
 272     void OnAssertFailure(const wxChar file, int line,
 273                          const wxChar func,
 274                          const wxChar cond,
 275                          const wxChar msg);
 276
 277     /**
 278         Called when command line parsing fails (i.e. an incorrect command line option
 279         was specified by the user). The default behaviour is to show the program usage
 280         text and abort the program.
 281         Return @true to continue normal execution or @false to return
 282         @false from OnInit() thus terminating the program.
 283
 284         @see OnInitCmdLine()
 285     */
 286     bool OnCmdLineError(wxCmdLineParser& parser);
 287
 288     /**
 289         Called when the help option (@c --help) was specified on the command line.
 290         The default behaviour is to show the program usage text and abort the program.
 291         Return @true to continue normal execution or @false to return
 292         @false from OnInit() thus terminating the program.
 293
 294         @see OnInitCmdLine()
 295     */
 296     bool OnCmdLineHelp(wxCmdLineParser& parser);
 297
 298     /**
 299         Called after the command line had been successfully parsed. You may override
 300         this method to test for the values of the various parameters which could be
 301         set from the command line.
 302         Don't forget to call the base class version unless you want to suppress
 303         processing of the standard command line options.
 304         Return @true to continue normal execution or @false to return
 305         @false from OnInit() thus terminating the program.
 306
 307         @see OnInitCmdLine()
 308     */
 309     bool OnCmdLineParsed(wxCmdLineParser& parser);
 310
 311     /**
 312         This function is called if an unhandled exception occurs inside the main
 313         application event loop. It can return @true to ignore the exception and to
 314         continue running the loop or @false to exit the loop and terminate the
 315         program. In the latter case it can also use C++ @c throw keyword to
 316         rethrow the current exception.
 317         The default behaviour of this function is the latter in all ports except under
 318         Windows where a dialog is shown to the user which allows him to choose between
 319         the different options. You may override this function in your class to do
 320         something more appropriate.
 321         Finally note that if the exception is rethrown from here, it can be caught in
 322         OnUnhandledException().
 323     */
 324     virtual bool OnExceptionInMainLoop();
 325
 326     /**
 327         Override this member function for any processing which needs to be
 328         done as the application is about to exit. OnExit is called after
 329         destroying all application windows and controls, but before
 330         wxWidgets cleanup. Note that it is not called at all if
 331         OnInit() failed.
 332         The return value of this function is currently ignored, return the same value
 333         as returned by the base class method if you override it.
 334     */
 335     virtual int OnExit();
 336
 337     /**
 338         This function may be called if something fatal happens: an unhandled
 339         exception under Win32 or a a fatal signal under Unix, for example. However,
 340         this will not happen by default: you have to explicitly call
 341         wxHandleFatalExceptions to enable this.
 342         Generally speaking, this function should only show a message to the user and
 343         return. You may attempt to save unsaved data but this is not guaranteed to
 344         work and, in fact, probably won't.
 345
 346         @see wxHandleFatalExceptions
 347     */
 348     void OnFatalException();
 349
 350     /**
 351         This must be provided by the application, and will usually create the
 352         application's main window, optionally calling
 353         SetTopWindow(). You may use
 354         OnExit() to clean up anything initialized here, provided
 355         that the function returns @true.
 356         Notice that if you want to to use the command line processing provided by
 357         wxWidgets you have to call the base class version in the derived class
 358         OnInit().
 359         Return @true to continue processing, @false to exit the application
 360         immediately.
 361     */
 362     bool OnInit();
 363
 364     /**
 365         Called from OnInit() and may be used to initialize the
 366         parser with the command line options for this application. The base class
 367         versions adds support for a few standard options only.
 368     */
 369     void OnInitCmdLine(wxCmdLineParser& parser);
 370
 371     /**
 372         This virtual function is where the execution of a program written in wxWidgets
 373         starts. The default implementation just enters the main loop and starts
 374         handling the events until it terminates, either because
 375         ExitMainLoop() has been explicitly called or because
 376         the last frame has been deleted and
 377         GetExitOnFrameDelete() flag is @true (this
 378         is the default).
 379         The return value of this function becomes the exit code of the program, so it
 380         should return 0 in case of successful termination.
 381     */
 382     virtual int OnRun();
 383
 384     /**
 385         This function is called when an unhandled C++ exception occurs inside
 386         OnRun() (the exceptions which occur during the program
 387         startup and shutdown might not be caught at all). Notice that by now the main
 388         event loop has been terminated and the program will exit, if you want to
 389         prevent this from happening (i.e. continue running after catching an exception)
 390         you need to override OnExceptionInMainLoop().
 391         The default implementation shows information about the exception in debug build
 392         but does nothing in the release build.
 393     */
 394     virtual void OnUnhandledException();
 395
 396     /**
 397         Returns @true if unprocessed events are in the window system event queue.
 398
 399         @see Dispatch()
 400     */
 401     virtual bool Pending();
 402
 403     /**
 404         Windows-only function for processing a message. This function
 405         is called from the main message loop, checking for windows that
 406         may wish to process it. The function returns @true if the message
 407         was processed, @false otherwise. If you use wxWidgets with another class
 408         library with its own message loop, you should make sure that this
 409         function is called to allow wxWidgets to receive messages. For example,
 410         to allow co-existence with the Microsoft Foundation Classes, override
 411         the PreTranslateMessage function:
 412     */
 413     bool ProcessMessage(WXMSG* msg);
 414
 415     /**
 416         Sends idle events to a window and its children.
 417         Please note that this function is internal to wxWidgets and shouldn't be used
 418         by user code.
 419
 420         @remarks These functions poll the top-level windows, and their children,
 421                  for idle event processing. If @true is returned, more
 422                  OnIdle processing is requested by one or more window.
 423
 424         @see wxIdleEvent
 425     */
 426     bool SendIdleEvents(wxWindow* win, wxIdleEvent& event);
 427
 428     /**
 429         Set the application name to be used in the user-visible places such as window
 430         titles. See GetAppDisplayName() for more about
 431         the differences between the display name and name.
 432     */
 433     void SetAppDisplayName(const wxString& name);
 434
 435     /**
 436         Sets the name of the application. This name should be used for file names,
 437         configuration file entries and other internal strings. For the user-visible
 438         strings, such as the window titles, the application display name set by
 439         SetAppDisplayName() is used instead.
 440         By default the application name is set to the name of its executable file.
 441
 442         @see GetAppName()
 443     */
 444     void SetAppName(const wxString& name);
 445
 446     /**
 447         Sets the class name of the application. This may be used in a platform specific
 448         manner to refer to the application.
 449
 450         @see GetClassName()
 451     */
 452     void SetClassName(const wxString& name);
 453
 454     /**
 455         Allows the programmer to specify whether the application will exit when the
 456         top-level frame is deleted.
 457
 458         @param flag
 459             If @true (the default), the application will exit when the top-level frame is
 460             deleted. If @false, the application will continue to run.
 461
 462         @see GetExitOnFrameDelete(), @ref overview_wxappshutdownoverview "wxApp
 463              shutdown overview"
 464     */
 465     void SetExitOnFrameDelete(bool flag);
 466
 467     /**
 468         Allows external code to modify global @c wxTheApp, but you should really
 469         know what you're doing if you call it.
 470
 471         @param app
 472             Replacement for the global application object.
 473
 474         @see GetInstance()
 475     */
 476     static void SetInstance(wxAppConsole* app);
 477
 478     /**
 479         Allows runtime switching of the UI environment theme. Currently implemented for
 480         wxGTK2-only.
 481         Return @true if theme was successfully changed.
 482
 483         @param theme
 484             The name of the new theme or an absolute path to a gtkrc-theme-file
 485     */
 486     bool SetNativeTheme();
 487
 488     /**
 489         Sets the 'top' window. You can call this from within OnInit() to
 490         let wxWidgets know which is the main window. You don't have to set the top
 491         window;
 492         it is only a convenience so that (for example) certain dialogs without parents
 493         can use a
 494         specific window as the top window. If no top window is specified by the
 495         application,
 496         wxWidgets just uses the first frame or dialog in its top-level window list,
 497         when it
 498         needs to use the top window.
 499
 500         @param window
 501             The new top window.
 502
 503         @see GetTopWindow(), OnInit()
 504     */
 505     void SetTopWindow(wxWindow* window);
 506
 507     /**
 508         Allows the programmer to specify whether the application will use the best
 509         visual
 510         on systems that support several visual on the same display. This is typically
 511         the
 512         case under Solaris and IRIX, where the default visual is only 8-bit whereas
 513         certain
 514         applications are supposed to run in TrueColour mode.
 515         If @a forceTrueColour is @true then the application will try to force
 516         using a TrueColour visual and abort the app if none is found.
 517         Note that this function has to be called in the constructor of the @c wxApp
 518         instance and won't have any effect when called later on.
 519         This function currently only has effect under GTK.
 520
 521         @param flag
 522             If @true, the app will use the best visual.
 523     */
 524     void SetUseBestVisual(bool flag, bool forceTrueColour = false);
 525
 526     /**
 527         Set the vendor name to be used in the user-visible places. See
 528         GetVendorDisplayName() for more about
 529         the differences between the display name and name.
 530     */
 531     void SetVendorDisplayName(const wxString& name);
 532
 533     /**
 534         Sets the name of application's vendor. The name will be used
 535         in registry access. A default name is set by
 536         wxWidgets.
 537
 538         @see GetVendorName()
 539     */
 540     void SetVendorName(const wxString& name);
 541
 542     /**
 543         Yields control to pending messages in the windowing system. This can be useful,
 544         for example, when a
 545         time-consuming process writes to a text window. Without an occasional
 546         yield, the text window will not be updated properly, and on systems with
 547         cooperative multitasking, such as Windows 3.1 other processes will not respond.
 548         Caution should be exercised, however, since yielding may allow the
 549         user to perform actions which are not compatible with the current task.
 550         Disabling menu items or whole menus during processing can avoid unwanted
 551         reentrance of code: see ::wxSafeYield for a better
 552         function.
 553         Note that Yield() will not flush the message logs. This is intentional as
 554         calling Yield() is usually done to quickly update the screen and popping up a
 555         message box dialog may be undesirable. If you do wish to flush the log
 556         messages immediately (otherwise it will be done during the next idle loop
 557         iteration), call wxLog::FlushActive.
 558         Calling Yield() recursively is normally an error and an assert failure is
 559         raised in debug build if such situation is detected. However if the
 560         @a onlyIfNeeded parameter is @true, the method will just silently
 561         return @false instead.
 562     */
 563     bool Yield(bool onlyIfNeeded = false);
 564
 565     /**
 566         int argc
 567         Number of command line arguments (after environment-specific processing).
 568     */
 569
 570
 571     /**
 572         wxChar ** argv
 573         Command line arguments (after environment-specific processing).
 574         Under Windows and Linux/Unix, you should parse the command line
 575         arguments and check for files to be opened when starting your
 576         application. Under OS X, you need to override MacOpenFile()
 577         since command line arguments are used differently there.
 578         You may use the wxCmdLineParser to
 579         parse command line arguments.
 580     */
 581 };
 582
 583
 584 // ============================================================================
 585 // Global functions/macros
 586 // ============================================================================
 587
 588 //@{
 589 /**
 590     For all normal, informational messages. They also appear in a message box by
 591     default (but it can be changed).
 592 */
 593 void wxLogMessage(const char* formatString, ... );
 594 void wxVLogMessage(const char* formatString, va_list argPtr);
 595 //@}
 596
 597 //@{
 598 /**
 599     For verbose output. Normally, it is suppressed, but
 600     might be activated if the user wishes to know more details about the program
 601     progress (another, but possibly confusing name for the same function is @b
 602     wxLogInfo).
 603 */
 604 void wxLogVerbose(const char* formatString, ... );
 605 void wxVLogVerbose(const char* formatString, va_list argPtr);
 606 //@}
 607
 608 /**
 609     This is used in headers to create a forward declaration of the
 610     wxGetApp function implemented by
 611     wxIMPLEMENT_APP. It creates the declaration
 612     @c className wxGetApp(void).
 613     Example:
 614
 615     @code
 616     wxDECLARE_APP(MyApp)
 617     @endcode
 618 */
 619 #define wxDECLARE_APP()     /* implementation is private */
 620
 621 /**
 622     Exits application after calling wxApp::OnExit.
 623     Should only be used in an emergency: normally the top-level frame
 624     should be deleted (after deleting all other frames) to terminate the
 625     application. See wxCloseEvent and wxApp.
 626 */
 627 void wxExit();
 628
 629 //@{
 630 /**
 631     For warnings - they are also normally shown to the user, but don't interrupt
 632     the program work.
 633 */
 634 void wxLogWarning(const char* formatString, ... );
 635 void wxVLogWarning(const char* formatString, va_list argPtr);
 636 //@}
 637
 638 //@{
 639 /**
 640     Like wxLogError, but also
 641     terminates the program with the exit code 3. Using @e abort() standard
 642     function also terminates the program with this exit code.
 643 */
 644 void wxLogFatalError(const char* formatString, ... );
 645 void wxVLogFatalError(const char* formatString,
 646                       va_list argPtr);
 647 //@}
 648
 649 /**
 650     If @a doIt is @true, the fatal exceptions (also known as general protection
 651     faults under Windows or segmentation violations in the Unix world) will be
 652     caught and passed to wxApp::OnFatalException.
 653     By default, i.e. before this function is called, they will be handled in the
 654     normal way which usually just means that the application will be terminated.
 655     Calling wxHandleFatalExceptions() with @a doIt equal to @false will restore
 656     this default behaviour.
 657     Notice that this function is only available if
 658     @c wxUSE_ON_FATAL_EXCEPTION is 1 and under Windows platform this
 659     requires a compiler with support for SEH (structured exception handling) which
 660     currently means only Microsoft Visual C++ or a recent Borland C++ version.
 661 */
 662 bool wxHandleFatalExceptions(bool doIt = true);
 663
 664 /**
 665     This is used in the application class implementation file to make the
 666     application class known to
 667     wxWidgets for dynamic construction. You use this instead of
 668     Old form:
 669
 670     @code
 671     MyApp myApp;
 672     @endcode
 673
 674     New form:
 675
 676     @code
 677     IMPLEMENT_APP(MyApp)
 678     @endcode
 679
 680     See also DECLARE_APP.
 681 */
 682 #define IMPLEMENT_APP()     /* implementation is private */
 683
 684 /**
 685     Returns the error code from the last system call. This function uses
 686     @c errno on Unix platforms and @c GetLastError under Win32.
 687
 688     @see wxSysErrorMsg, wxLogSysError
 689 */
 690 unsigned long wxSysErrorCode();
 691
 692 /**
 693     In a GUI application, this function posts @a event to the specified @e dest
 694     object using wxEvtHandler::AddPendingEvent.
 695     Otherwise, it dispatches @a event immediately using
 696     wxEvtHandler::ProcessEvent.
 697     See the respective documentation for details (and caveats).
 698 */
 699 void wxPostEvent(wxEvtHandler* dest, wxEvent& event);
 700
 701 //@{
 702 /**
 703     The functions to use for error messages, i.e. the messages that must be shown
 704     to the user. The default processing is to pop up a message box to inform the
 705     user about it.
 706 */
 707 void wxLogError(const char* formatString, ... );
 708 void wxVLogError(const char* formatString, va_list argPtr);
 709 //@}
 710
 711 //@{
 712 /**
 713     As @b wxLogDebug, trace functions only do something in debug build and
 714     expand to nothing in the release one. The reason for making
 715     it a separate function from it is that usually there are a lot of trace
 716     messages, so it might make sense to separate them from other debug messages.
 717     The trace messages also usually can be separated into different categories and
 718     the second and third versions of this function only log the message if the
 719     @a mask which it has is currently enabled in wxLog. This
 720     allows to selectively trace only some operations and not others by changing
 721     the value of the trace mask (possible during the run-time).
 722     For the second function (taking a string mask), the message is logged only if
 723     the mask has been previously enabled by the call to
 724     wxLog::AddTraceMask or by setting
 725     @ref overview_envvars "@c WXTRACE environment variable".
 726     The predefined string trace masks
 727     used by wxWidgets are:
 728      wxTRACE_MemAlloc: trace memory allocation (new/delete)
 729      wxTRACE_Messages: trace window messages/X callbacks
 730      wxTRACE_ResAlloc: trace GDI resource allocation
 731      wxTRACE_RefCount: trace various ref counting operations
 732      wxTRACE_OleCalls: trace OLE method calls (Win32 only)
 733     @b Caveats: since both the mask and the format string are strings,
 734     this might lead to function signature confusion in some cases:
 735     if you intend to call the format string only version of wxLogTrace,
 736     then add a %s format string parameter and then supply a second string parameter
 737     for that %s, the string mask version of wxLogTrace will erroneously get called instead, since you are supplying two string parameters to the function.
 738     In this case you'll unfortunately have to avoid having two leading
 739     string parameters, e.g. by adding a bogus integer (with its %d format string).
 740     The third version of the function only logs the message if all the bits
 741     corresponding to the @a mask are set in the wxLog trace mask which can be
 742     set by wxLog::SetTraceMask. This version is less
 743     flexible than the previous one because it doesn't allow defining the user
 744     trace masks easily - this is why it is deprecated in favour of using string
 745     trace masks.
 746      wxTraceMemAlloc: trace memory allocation (new/delete)
 747      wxTraceMessages: trace window messages/X callbacks
 748      wxTraceResAlloc: trace GDI resource allocation
 749      wxTraceRefCount: trace various ref counting operations
 750      wxTraceOleCalls: trace OLE method calls (Win32 only)
 751 */
 752 void wxLogTrace(const char* formatString, ... );
 753 void wxVLogTrace(const char* formatString, va_list argPtr);
 754 void wxLogTrace(const char* mask, const char* formatString,
 755                 ... );
 756 void wxVLogTrace(const char* mask,
 757                  const char* formatString,
 758                  va_list argPtr);
 759 void wxLogTrace(wxTraceMask mask, const char* formatString,
 760                 ... );
 761 void wxVLogTrace(wxTraceMask mask, const char* formatString,
 762                  va_list argPtr);
 763 //@}
 764
 765 /**
 766     Returns the error message corresponding to the given system error code. If
 767     @a errCode is 0 (default), the last error code (as returned by
 768     wxSysErrorCode) is used.
 769
 770     @see wxSysErrorCode, wxLogSysError
 771 */
 772 const wxChar* wxSysErrorMsg(unsigned long errCode = 0);
 773
 774 /**
 775     This function is for use in console (wxBase) programs only. It must be called
 776     once for each previous successful call to wxInitialize.
 777 */
 778 void wxUninitialize();
 779
 780 //@{
 781 /**
 782     The right functions for debug output. They only do something in debug
 783     mode (when the preprocessor symbol __WXDEBUG__ is defined) and expand to
 784     nothing in release mode (otherwise).
 785 */
 786 void wxLogDebug(const char* formatString, ... );
 787 void wxVLogDebug(const char* formatString, va_list argPtr);
 788 //@}
 789
 790 /**
 791     This function doesn't exist in wxWidgets but it is created by using
 792     the IMPLEMENT_APP macro. Thus, before using it
 793     anywhere but in the same module where this macro is used, you must make it
 794     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 @c wxApp * and so wouldn't
 797     allow you to access the functions specific to your application class but not
 798     present in wxApp while wxGetApp() returns the object of the right type.
 799 */
 800 wxAppDerivedClass wxGetApp();
 801
 802 //@{
 803 /**
 804     Messages logged by these functions will appear in the statusbar of the @a frame
 805     or of the top level application window by default (i.e. when using
 806     the second version of the functions).
 807     If the target frame doesn't have a statusbar, the message will be lost.
 808 */
 809 void wxLogStatus(wxFrame* frame, const char* formatString,
 810                  ... );
 811 void wxVLogStatus(wxFrame* frame, const char* formatString,
 812                   va_list argPtr);
 813 void wxLogStatus(const char* formatString, ... );
 814 void wxVLogStatus(const char* formatString, va_list argPtr);
 815 //@}
 816
 817 /**
 818     This function is used in wxBase only and only if you don't create
 819     wxApp object at all. In this case you must call it from your
 820     @c main() function before calling any other wxWidgets functions.
 821     If the function returns @false the initialization could not be performed,
 822     in this case the library cannot be used and
 823     wxUninitialize shouldn't be called neither.
 824     This function may be called several times but
 825     wxUninitialize must be called for each successful
 826     call to this function.
 827 */
 828 bool wxInitialize();
 829
 830 /**
 831     This is used in headers to create a forward declaration of the
 832     wxGetApp function implemented by
 833     IMPLEMENT_APP. It creates the declaration
 834     @c className wxGetApp(void).
 835     Example:
 836
 837     @code
 838     DECLARE_APP(MyApp)
 839     @endcode
 840 */
 841 #define DECLARE_APP()     /* implementation is private */
 842
 843 /**
 844     Calls wxApp::Yield.
 845     This function is kept only for backwards compatibility. Please use
 846     the wxApp::Yield method instead in any new code.
 847 */
 848 bool wxYield();
 849
 850 //@{
 851 /**
 852     Mostly used by wxWidgets itself, but might be handy for logging errors after
 853     system call (API function) failure. It logs the specified message text as well
 854     as the last system error code (@e errno or @e ::GetLastError() depending
 855     on the platform) and the corresponding error message. The second form
 856     of this function takes the error code explicitly as the first argument.
 857
 858     @see wxSysErrorCode, wxSysErrorMsg
 859 */
 860 void wxLogSysError(const char* formatString, ... );
 861 void wxVLogSysError(const char* formatString,
 862                     va_list argPtr);
 863 //@}
 864
 865 //@{
 866 /**
 867     This initializes wxWidgets in a platform-dependent way. Use this if you are not
 868     using the default wxWidgets entry code (e.g. main or WinMain). For example, you
 869     can initialize wxWidgets from an Microsoft Foundation Classes application using
 870     this function.
 871     The following overload of wxEntry is available under all platforms:
 872
 873     (notice that under Windows CE platform, and only there, the type of
 874     @a pCmdLine is @c wchar_t *, otherwise it is @c char *, even in
 875     Unicode build).
 876
 877     @remarks To clean up wxWidgets, call wxApp::OnExit followed by the static
 878              function wxApp::CleanUp. For example, if exiting from
 879              an MFC application that also uses wxWidgets:
 880
 881     @see wxEntryStart
 882 */
 883 int wxEntry(int& argc, wxChar** argv);
 884 int wxEntry(HINSTANCE hInstance,
 885             HINSTANCE hPrevInstance = NULL,
 886             char* pCmdLine = NULL,
 887             int nCmdShow = SW_SHOWNORMAL);
 888 //@}
 889