include/wx/app.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        app.h
   3 // Purpose:     wxAppBase class and macros used for declaration of wxApp
   4 //              derived class in the user code
   5 // Author:      Julian Smart
   6 // Modified by:
   7 // Created:     01/02/97
   8 // RCS-ID:      $Id$
   9 // Copyright:   (c) Julian Smart and Markus Holzem
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 #ifndef _WX_APP_H_BASE_
  14 #define _WX_APP_H_BASE_
  15
  16 #ifdef __GNUG__
  17     #pragma interface "appbase.h"
  18 #endif
  19
  20 // ----------------------------------------------------------------------------
  21 // typedefs
  22 // ----------------------------------------------------------------------------
  23
  24 #ifdef __WXMSW__
  25     class WXDLLEXPORT wxApp;
  26     typedef wxApp* (*wxAppInitializerFunction)();
  27 #else
  28     // returning wxApp* won't work with gcc
  29     #include "wx/object.h"
  30
  31     typedef wxObject* (*wxAppInitializerFunction)();
  32 #endif
  33
  34 // ----------------------------------------------------------------------------
  35 // headers we have to include here
  36 // ----------------------------------------------------------------------------
  37
  38 #include "wx/event.h"       // for the base class
  39
  40 #if wxUSE_GUI
  41     #include "wx/window.h"      // for wxTopLevelWindows
  42 #endif // wxUSE_GUI
  43
  44 #if wxUSE_LOG
  45     #include "wx/log.h"
  46 #endif
  47
  48 // ----------------------------------------------------------------------------
  49 // constants
  50 // ----------------------------------------------------------------------------
  51
  52 static const int wxPRINT_WINDOWS = 1;
  53 static const int wxPRINT_POSTSCRIPT = 2;
  54
  55 // ----------------------------------------------------------------------------
  56 // the common part of wxApp implementations for all platforms
  57 // ----------------------------------------------------------------------------
  58
  59 class WXDLLEXPORT wxAppBase : public wxEvtHandler
  60 {
  61 public:
  62     // the virtual functions which may/must be overridden in the derived class
  63     // -----------------------------------------------------------------------
  64
  65         // called during the program initialization, returning FALSE from here
  66         // prevents the program from continuing - it's a good place to create
  67         // the top level program window and return TRUE.
  68         //
  69         // Override: always in GUI application, rarely in console ones.
  70 #if wxUSE_GUI
  71     virtual bool OnInit() { return FALSE; };
  72 #else // !GUI
  73     virtual bool OnInit() { return TRUE; };
  74 #endif // wxUSE_GUI
  75
  76 #if wxUSE_GUI
  77         // a platform-dependent version of OnInit(): the code here is likely to
  78         // depend on the toolkit. default version does nothing.
  79         //
  80         // Override: rarely.
  81     virtual bool OnInitGui() { return TRUE; }
  82 #endif // wxUSE_GUI
  83
  84         // called to start program execution - the default version just enters
  85         // the main GUI loop in which events are received and processed until
  86         // the last window is not deleted (if GetExitOnFrameDelete) or
  87         // ExitMainLoop() is called. In console mode programs, the execution
  88         // of the program really starts here
  89         //
  90         // Override: rarely in GUI applications, always in console ones.
  91 #if wxUSE_GUI
  92     virtual int OnRun() { return MainLoop(); };
  93 #else // !GUI
  94     virtual int OnRun() = 0;
  95 #endif // wxUSE_GUI
  96
  97         // called after the main loop termination. This is a good place for
  98         // cleaning up (it may be too late in dtor) and is also useful if you
  99         // want to return some non-default exit code - this is just the return
 100         // value of this method.
 101         //
 102         // Override: often.
 103     virtual int OnExit();
 104
 105         // called when a fatal exception occurs, this function should take care
 106         // not to do anything which might provoke a nested exception! It may be
 107         // overridden if you wish to react somehow in non-default way (core
 108         // dump under Unix, application crash under Windows) to fatal program
 109         // errors, however extreme care should be taken if you don't want this
 110         // function to crash.
 111         //
 112         // Override: rarely.
 113     virtual void OnFatalException() { }
 114
 115     // the worker functions - usually not used directly by the user code
 116     // -----------------------------------------------------------------
 117
 118 #if wxUSE_GUI
 119         // execute the main GUI loop, the function returns when the loop ends
 120     virtual int MainLoop() = 0;
 121
 122         // exit the main GUI loop during the next iteration (i.e. it does not
 123         // stop the program immediately!)
 124     virtual void ExitMainLoop() = 0;
 125
 126         // returns TRUE if the program is initialized
 127     virtual bool Initialized() = 0;
 128
 129         // returns TRUE if there are unprocessed events in the event queue
 130     virtual bool Pending() = 0;
 131
 132         // process the first event in the event queue (blocks until an event
 133         // apperas if there are none currently)
 134     virtual void Dispatch() = 0;
 135 #endif // wxUSE_GUI
 136
 137     // application info: name, description, vendor
 138     // -------------------------------------------
 139
 140     // NB: all these should be set by the application itself, there are no
 141     //     reasonable default except for the application name which is taken to
 142     //     be argv[0]
 143
 144         // set/get the application name
 145     wxString GetAppName() const
 146     {
 147         if ( !m_appName )
 148             return m_className;
 149         else
 150             return m_appName;
 151     }
 152     void SetAppName(const wxString& name) { m_appName = name; }
 153
 154         // set/get the app class name
 155     wxString GetClassName() const { return m_className; }
 156     void SetClassName(const wxString& name) { m_className = name; }
 157
 158         // set/get the vendor name
 159     const wxString& GetVendorName() const { return m_vendorName; }
 160     void SetVendorName(const wxString& name) { m_vendorName = name; }
 161
 162 #if wxUSE_GUI
 163     // top level window functions
 164     // --------------------------
 165
 166         // set the "main" top level window
 167     void SetTopWindow(wxWindow *win) { m_topWindow = win; }
 168
 169         // return the "main" top level window (if it hadn't been set previously
 170         // with SetTopWindow(), will return just some top level window and, if
 171         // there are none, will return NULL)
 172     wxWindow *GetTopWindow() const
 173     {
 174         if (m_topWindow)
 175             return m_topWindow;
 176         else if (wxTopLevelWindows.GetCount() > 0)
 177             return wxTopLevelWindows.GetFirst()->GetData();
 178         else
 179             return (wxWindow *)NULL;
 180     }
 181
 182         // control the exit behaviour: by default, the program will exit the
 183         // main loop (and so, usually, terminate) when the last top-level
 184         // program window is deleted. Beware that if you disabel this (with
 185         // SetExitOnFrameDelete(FALSE)), you'll have to call ExitMainLoop()
 186         // explicitly from somewhere.
 187     void SetExitOnFrameDelete(bool flag) { m_exitOnFrameDelete = flag; }
 188     bool GetExitOnFrameDelete() const { return m_exitOnFrameDelete; }
 189
 190 #endif // wxUSE_GUI
 191
 192     // miscellaneous customization functions
 193     // -------------------------------------
 194
 195 #if wxUSE_LOG
 196         // override this function to create default log target of arbitrary
 197         // user-defined class (default implementation creates a wxLogGui
 198         // object) - this log object is used by default by all wxLogXXX()
 199         // functions.
 200     virtual wxLog *CreateLogTarget()
 201 #if wxUSE_GUI
 202         { return new wxLogGui; }
 203 #else // !GUI
 204         { return new wxLogStderr; }
 205 #endif // wxUSE_GUI
 206 #endif // wxUSE_LOG
 207
 208 #if wxUSE_GUI
 209         // get the standard icon used by wxWin dialogs - this allows the user
 210         // to customize the standard dialogs. The 'which' parameter is one of
 211         // wxICON_XXX values
 212     virtual wxIcon GetStdIcon(int which) const = 0;
 213
 214         // VZ: what does this do exactly?
 215     void SetWantDebugOutput( bool flag ) { m_wantDebugOutput = flag; }
 216     bool GetWantDebugOutput() const { return m_wantDebugOutput; }
 217
 218         // set use of best visual flag (see below)
 219     void SetUseBestVisual( bool flag ) { m_useBestVisual = flag; }
 220     bool GetUseBestVisual() const { return m_useBestVisual; }
 221
 222         // set/get printing mode: see wxPRINT_XXX constants.
 223         //
 224         // default behaviour is the normal one for Unix: always use PostScript
 225         // printing.
 226     virtual void SetPrintMode(int WXUNUSED(mode)) { }
 227     int GetPrintMode() const { return wxPRINT_POSTSCRIPT; }
 228 #endif // wxUSE_GUI
 229
 230     // implementation only from now on
 231     // -------------------------------
 232
 233     // helpers for dynamic wxApp construction
 234     static void SetInitializerFunction(wxAppInitializerFunction fn)
 235         { m_appInitFn = fn; }
 236     static wxAppInitializerFunction GetInitializerFunction()
 237         { return m_appInitFn; }
 238
 239     // process all events in the wxPendingEvents list
 240     virtual void ProcessPendingEvents();
 241
 242     // access to the command line arguments
 243     int      argc;
 244     wxChar **argv;
 245
 246 //private:
 247 protected:
 248     // function used for dynamic wxApp creation
 249     static wxAppInitializerFunction m_appInitFn;
 250
 251     // application info (must be set from the user code)
 252     wxString m_vendorName,      // vendor name (ACME Inc)
 253              m_appName,         // app name
 254              m_className;       // class name
 255
 256     // if TRUE, exit the main loop when the last top level window is deleted
 257     bool m_exitOnFrameDelete;
 258
 259     // TRUE if the application wants to get debug output
 260     bool m_wantDebugOutput;
 261
 262     // TRUE if the apps whats to use the best visual on systems where
 263     // more than one are available (Sun, SGI, XFree86 4.0 ?)
 264     bool m_useBestVisual;
 265
 266 #if wxUSE_GUI
 267     // the main top level window - may be NULL
 268     wxWindow *m_topWindow;
 269 #endif // wxUSE_GUI
 270 };
 271
 272 // ----------------------------------------------------------------------------
 273 // now include the declaration of the real class
 274 // ----------------------------------------------------------------------------
 275
 276 #if wxUSE_GUI
 277     #if defined(__WXMSW__)
 278         #include "wx/msw/app.h"
 279     #elif defined(__WXMOTIF__)
 280         #include "wx/motif/app.h"
 281     #elif defined(__WXQT__)
 282         #include "wx/qt/app.h"
 283     #elif defined(__WXGTK__)
 284         #include "wx/gtk/app.h"
 285     #elif defined(__WXMAC__)
 286         #include "wx/mac/app.h"
 287     #elif defined(__WXPM__)
 288         #include "wx/os2/app.h"
 289     #elif defined(__WXSTUBS__)
 290         #include "wx/stubs/app.h"
 291     #endif
 292 #else // !GUI
 293     // can't use typedef because wxApp forward declared as a class
 294     class WXDLLEXPORT wxApp : public wxAppBase
 295     {
 296     };
 297 #endif // GUI/!GUI
 298
 299 // ----------------------------------------------------------------------------
 300 // the global data
 301 // ----------------------------------------------------------------------------
 302
 303 // the one and only application object - use of wxTheApp in application code
 304 // is discouraged, consider using DECLARE_APP() after which you may call
 305 // wxGetApp() which will return the object of the correct type (i.e. MyApp and
 306 // not wxApp)
 307 WXDLLEXPORT_DATA(extern wxApp*) wxTheApp;
 308
 309 // ----------------------------------------------------------------------------
 310 // global functions
 311 // ----------------------------------------------------------------------------
 312
 313 // event loop related functions only work in GUI programs
 314 // ------------------------------------------------------
 315
 316 // Force an exit from main loop
 317 extern void WXDLLEXPORT wxExit();
 318
 319 // Yield to other apps/messages
 320 extern bool WXDLLEXPORT wxYield();
 321
 322 // Yield to other apps/messages
 323 extern void WXDLLEXPORT wxWakeUpIdle();
 324
 325 #if wxUSE_GUI
 326
 327 // Post a message to the given eventhandler which will be processed during the
 328 // next event loop iteration
 329 inline void WXDLLEXPORT wxPostEvent(wxEvtHandler *dest, wxEvent& event)
 330 {
 331     wxCHECK_RET( dest, wxT("need an object to post event to in wxPostEvent") );
 332
 333     dest->AddPendingEvent(event);
 334 }
 335
 336 #endif // wxUSE_GUI
 337
 338 // console applications may avoid using DECLARE_APP and IMPLEMENT_APP macros
 339 // and call these functions instead at the program startup and termination
 340 // -------------------------------------------------------------------------
 341
 342 #if !wxUSE_GUI
 343
 344 // initialize the library (may be called as many times as needed, but each
 345 // call to wxInitialize() must be matched by wxUninitialize())
 346 extern bool WXDLLEXPORT wxInitialize();
 347
 348 // clean up - the library can't be used any more after the last call to
 349 // wxUninitialize()
 350 extern void WXDLLEXPORT wxUninitialize();
 351
 352 #endif // !wxUSE_GUI
 353
 354 // ----------------------------------------------------------------------------
 355 // macros for dynamic creation of the application object
 356 // ----------------------------------------------------------------------------
 357
 358 // Having a global instance of this class allows wxApp to be aware of the app
 359 // creator function. wxApp can then call this function to create a new app
 360 // object. Convoluted, but necessary.
 361
 362 class WXDLLEXPORT wxAppInitializer
 363 {
 364 public:
 365     wxAppInitializer(wxAppInitializerFunction fn)
 366         { wxApp::SetInitializerFunction(fn); }
 367 };
 368
 369 // Here's a macro you can use if your compiler really, really wants main() to
 370 // be in your main program (e.g. hello.cpp). Now IMPLEMENT_APP should add this
 371 // code if required.
 372
 373 #if !wxUSE_GUI || defined(__AIX__) || defined(__HPUX__) || defined( __VMS__ ) || defined(__WXPM__)
 374     #define IMPLEMENT_WXWIN_MAIN \
 375         extern int wxEntry( int argc, char *argv[] ); \
 376         int main(int argc, char *argv[]) { return wxEntry(argc, argv); }
 377 #elif defined(__WXMSW__) && defined(WXUSINGDLL)
 378     // NT defines APIENTRY, 3.x not
 379     #if !defined(WXAPIENTRY)
 380         #define WXAPIENTRY WXFAR wxSTDCALL
 381     #endif
 382
 383     #define IMPLEMENT_WXWIN_MAIN \
 384         int WXAPIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,\
 385                                LPSTR m_lpCmdLine, int nCmdShow )\
 386         {\
 387             return wxEntry((WXHINSTANCE) hInstance, \
 388                            (WXHINSTANCE) hPrevInstance,\
 389                            m_lpCmdLine, nCmdShow);\
 390         }
 391
 392 #else
 393     #define IMPLEMENT_WXWIN_MAIN
 394 #endif
 395
 396 // use this macro exactly once, the argument is the name of the wxApp-derived
 397 // class which is the class of your application
 398 #define IMPLEMENT_APP(appname)                          \
 399     wxApp *wxCreateApp() { return new appname; }      \
 400     wxAppInitializer wxTheAppInitializer((wxAppInitializerFunction) wxCreateApp); \
 401     appname& wxGetApp() { return *(appname *)wxTheApp; } \
 402     IMPLEMENT_WXWIN_MAIN
 403
 404 #define DECLARE_APP(appname) extern appname& wxGetApp();
 405
 406 #endif
 407     // _WX_APP_H_BASE_