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() { return 0; }
 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/get printing mode: see wxPRINT_XXX constants.
 219         //
 220         // default behaviour is the normal one for Unix: always use PostScript
 221         // printing.
 222     virtual void SetPrintMode(int WXUNUSED(mode)) { }
 223     int GetPrintMode() const { return wxPRINT_POSTSCRIPT; }
 224 #endif // wxUSE_GUI
 225
 226     // implementation only from now on
 227     // -------------------------------
 228
 229     // helpers for dynamic wxApp construction
 230     static void SetInitializerFunction(wxAppInitializerFunction fn)
 231         { m_appInitFn = fn; }
 232     static wxAppInitializerFunction GetInitializerFunction()
 233         { return m_appInitFn; }
 234
 235     // process all events in the wxPendingEvents list
 236     virtual void ProcessPendingEvents();
 237
 238     // access to the command line arguments
 239     int      argc;
 240     wxChar **argv;
 241
 242 //private:
 243 protected:
 244     // function used for dynamic wxApp creation
 245     static wxAppInitializerFunction m_appInitFn;
 246
 247     // application info (must be set from the user code)
 248     wxString m_vendorName,      // vendor name (ACME Inc)
 249              m_appName,         // app name
 250              m_className;       // class name
 251
 252     // if TRUE, exit the main loop when the last top level window is deleted
 253     bool m_exitOnFrameDelete;
 254
 255     // TRUE if the application wants to get debug output
 256     bool m_wantDebugOutput;
 257
 258 #if wxUSE_GUI
 259     // the main top level window - may be NULL
 260     wxWindow *m_topWindow;
 261 #endif // wxUSE_GUI
 262 };
 263
 264 // ----------------------------------------------------------------------------
 265 // now include the declaration of the real class
 266 // ----------------------------------------------------------------------------
 267
 268 #if wxUSE_GUI
 269     #if defined(__WXMSW__)
 270         #include "wx/msw/app.h"
 271     #elif defined(__WXMOTIF__)
 272         #include "wx/motif/app.h"
 273     #elif defined(__WXQT__)
 274         #include "wx/qt/app.h"
 275     #elif defined(__WXGTK__)
 276         #include "wx/gtk/app.h"
 277     #elif defined(__WXMAC__)
 278         #include "wx/mac/app.h"
 279     #elif defined(__WXPM__)
 280         #include "wx/os2/app.h"
 281     #elif defined(__WXSTUBS__)
 282         #include "wx/stubs/app.h"
 283     #endif
 284 #else // !GUI
 285     typedef wxAppBase wxApp;
 286 #endif // GUI/!GUI
 287
 288 // ----------------------------------------------------------------------------
 289 // the global data
 290 // ----------------------------------------------------------------------------
 291
 292 // the one and only application object - use of wxTheApp in application code
 293 // is discouraged, consider using DECLARE_APP() after which you may call
 294 // wxGetApp() which will return the object of the correct type (i.e. MyApp and
 295 // not wxApp)
 296 WXDLLEXPORT_DATA(extern wxApp*) wxTheApp;
 297
 298 // ----------------------------------------------------------------------------
 299 // global functions
 300 // ----------------------------------------------------------------------------
 301
 302 // event loop related functions only work in GUI programs
 303 // ------------------------------------------------------
 304
 305 #if wxUSE_GUI
 306
 307 // Force an exit from main loop
 308 extern void WXDLLEXPORT wxExit();
 309
 310 // Yield to other apps/messages
 311 extern bool WXDLLEXPORT wxYield();
 312
 313 // Post a message to the given eventhandler which will be processed during the
 314 // next event loop iteration
 315 inline void WXDLLEXPORT wxPostEvent(wxEvtHandler *dest, wxEvent& event)
 316 {
 317     wxCHECK_RET( dest, wxT("need an object to post event to in wxPostEvent") );
 318
 319     dest->AddPendingEvent(event);
 320 }
 321
 322 #endif // wxUSE_GUI
 323
 324 // console applications may avoid using DECLARE_APP and IMPLEMENT_APP macros
 325 // and call these functions instead at the program startup and termination
 326 // -------------------------------------------------------------------------
 327
 328 #if wxUSE_NOGUI
 329
 330 // initialize the library (may be called as many times as needed, but each
 331 // call to wxInitialize() must be matched by wxUninitialize())
 332 extern bool WXDLLEXPORT wxInitialize();
 333
 334 // clean up - the library can't be used any more after the last call to
 335 // wxUninitialize()
 336 extern void WXDLLEXPORT wxUninitialize();
 337
 338 #endif // wxUSE_NOGUI
 339
 340 // ----------------------------------------------------------------------------
 341 // macros for dynamic creation of the application object
 342 // ----------------------------------------------------------------------------
 343
 344 // Having a global instance of this class allows wxApp to be aware of the app
 345 // creator function. wxApp can then call this function to create a new app
 346 // object. Convoluted, but necessary.
 347
 348 class WXDLLEXPORT wxAppInitializer
 349 {
 350 public:
 351     wxAppInitializer(wxAppInitializerFunction fn)
 352         { wxApp::SetInitializerFunction(fn); }
 353 };
 354
 355 // Here's a macro you can use if your compiler really, really wants main() to
 356 // be in your main program (e.g. hello.cpp). Now IMPLEMENT_APP should add this
 357 // code if required.
 358
 359 #if defined(__AIX__) || defined(__HPUX__)
 360     #define IMPLEMENT_WXWIN_MAIN \
 361         extern int wxEntry( int argc, char *argv[] ); \
 362         int main(int argc, char *argv[]) { return wxEntry(argc, argv); }
 363 #elif defined(__WXMSW__) && defined(WXUSINGDLL)
 364     // NT defines APIENTRY, 3.x not
 365     #if !defined(WXAPIENTRY)
 366         #ifdef __WATCOMC__
 367             #define WXAPIENTRY PASCAL
 368         #else
 369             #define WXAPIENTRY FAR PASCAL
 370         #endif
 371     #endif
 372
 373     #define IMPLEMENT_WXWIN_MAIN \
 374         int WXAPIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,\
 375                                LPSTR m_lpCmdLine, int nCmdShow )\
 376         {\
 377             return wxEntry((WXHINSTANCE) hInstance, \
 378                            (WXHINSTANCE) hPrevInstance,\
 379                            m_lpCmdLine, nCmdShow);\
 380         }
 381
 382 #else
 383     #define IMPLEMENT_WXWIN_MAIN
 384 #endif
 385
 386 // use this macro exactly once, the argument is the name of the wxApp-derived
 387 // class which is the class of your application
 388 #define IMPLEMENT_APP(appname)                          \
 389     wxApp *wxCreateApp() { return new appname; }      \
 390     wxAppInitializer wxTheAppInitializer((wxAppInitializerFunction) wxCreateApp); \
 391     appname& wxGetApp() { return *(appname *)wxTheApp; } \
 392     IMPLEMENT_WXWIN_MAIN
 393
 394 #define DECLARE_APP(appname) extern appname& wxGetApp();
 395
 396 #endif
 397     // _WX_APP_H_BASE_