src/msw/app.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/msw/app.cpp
   3 // Purpose:     wxApp
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ===========================================================================
  13 // declarations
  14 // ===========================================================================
  15
  16 // ---------------------------------------------------------------------------
  17 // headers
  18 // ---------------------------------------------------------------------------
  19
  20 // For compilers that support precompilation, includes "wx.h".
  21 #include "wx/wxprec.h"
  22
  23 #if defined(__BORLANDC__)
  24     #pragma hdrstop
  25 #endif
  26
  27 #ifndef WX_PRECOMP
  28     #include "wx/msw/wrapcctl.h"
  29     #include "wx/dynarray.h"
  30     #include "wx/frame.h"
  31     #include "wx/app.h"
  32     #include "wx/utils.h"
  33     #include "wx/gdicmn.h"
  34     #include "wx/pen.h"
  35     #include "wx/brush.h"
  36     #include "wx/cursor.h"
  37     #include "wx/icon.h"
  38     #include "wx/palette.h"
  39     #include "wx/dc.h"
  40     #include "wx/dialog.h"
  41     #include "wx/msgdlg.h"
  42     #include "wx/intl.h"
  43     #include "wx/wxchar.h"
  44     #include "wx/log.h"
  45     #include "wx/module.h"
  46 #endif
  47
  48 #include "wx/apptrait.h"
  49 #include "wx/filename.h"
  50 #include "wx/dynlib.h"
  51 #include "wx/evtloop.h"
  52
  53 #include "wx/msw/private.h"
  54 #include "wx/msw/ole/oleutils.h"
  55
  56 #if wxUSE_TOOLTIPS
  57     #include "wx/tooltip.h"
  58 #endif // wxUSE_TOOLTIPS
  59
  60 // OLE is used for drag-and-drop, clipboard, OLE Automation..., but some
  61 // compilers don't support it (missing headers, libs, ...)
  62 #if defined(__GNUWIN32_OLD__) || defined(__SYMANTEC__) || defined(__SALFORDC__)
  63     #undef wxUSE_OLE
  64
  65     #define  wxUSE_OLE 0
  66 #endif // broken compilers
  67
  68 #if defined(__POCKETPC__) || defined(__SMARTPHONE__)
  69     #include <ole2.h>
  70     #include <aygshell.h>
  71 #endif
  72
  73 #if wxUSE_OLE
  74     #include <ole2.h>
  75 #endif
  76
  77 #include <string.h>
  78 #include <ctype.h>
  79
  80 #include "wx/msw/missing.h"
  81
  82 // instead of including <shlwapi.h> which is not part of the core SDK and not
  83 // shipped at all with other compilers, we always define the parts of it we
  84 // need here ourselves
  85 //
  86 // NB: DLLVER_PLATFORM_WINDOWS will be defined if shlwapi.h had been somehow
  87 //     included already
  88 #ifndef DLLVER_PLATFORM_WINDOWS
  89     // hopefully we don't need to change packing as DWORDs should be already
  90     // correctly aligned
  91     struct DLLVERSIONINFO
  92     {
  93         DWORD cbSize;
  94         DWORD dwMajorVersion;                   // Major version
  95         DWORD dwMinorVersion;                   // Minor version
  96         DWORD dwBuildNumber;                    // Build number
  97         DWORD dwPlatformID;                     // DLLVER_PLATFORM_*
  98     };
  99
 100     typedef HRESULT (CALLBACK* DLLGETVERSIONPROC)(DLLVERSIONINFO *);
 101 #endif // defined(DLLVERSIONINFO)
 102
 103
 104 // ---------------------------------------------------------------------------
 105 // global variables
 106 // ---------------------------------------------------------------------------
 107
 108 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 109 extern void wxSetKeyboardHook(bool doIt);
 110 #endif
 111
 112 // NB: all "NoRedraw" classes must have the same names as the "normal" classes
 113 //     with NR suffix - wxWindow::MSWCreate() supposes this
 114 #ifdef __WXWINCE__
 115 WXDLLIMPEXP_CORE       wxChar *wxCanvasClassName;
 116 WXDLLIMPEXP_CORE       wxChar *wxCanvasClassNameNR;
 117 #else
 118 WXDLLIMPEXP_CORE const wxChar *wxCanvasClassName        = wxT("wxWindowClass");
 119 WXDLLIMPEXP_CORE const wxChar *wxCanvasClassNameNR      = wxT("wxWindowClassNR");
 120 #endif
 121 WXDLLIMPEXP_CORE const wxChar *wxMDIFrameClassName      = wxT("wxMDIFrameClass");
 122 WXDLLIMPEXP_CORE const wxChar *wxMDIFrameClassNameNoRedraw = wxT("wxMDIFrameClassNR");
 123 WXDLLIMPEXP_CORE const wxChar *wxMDIChildFrameClassName = wxT("wxMDIChildFrameClass");
 124 WXDLLIMPEXP_CORE const wxChar *wxMDIChildFrameClassNameNoRedraw = wxT("wxMDIChildFrameClassNR");
 125
 126 // ----------------------------------------------------------------------------
 127 // private functions
 128 // ----------------------------------------------------------------------------
 129
 130 LRESULT WXDLLEXPORT APIENTRY wxWndProc(HWND, UINT, WPARAM, LPARAM);
 131
 132 // ===========================================================================
 133 // wxGUIAppTraits implementation
 134 // ===========================================================================
 135
 136 // private class which we use to pass parameters from BeforeChildWaitLoop() to
 137 // AfterChildWaitLoop()
 138 struct ChildWaitLoopData
 139 {
 140     ChildWaitLoopData(wxWindowDisabler *wd_, wxWindow *winActive_)
 141     {
 142         wd = wd_;
 143         winActive = winActive_;
 144     }
 145
 146     wxWindowDisabler *wd;
 147     wxWindow *winActive;
 148 };
 149
 150 void *wxGUIAppTraits::BeforeChildWaitLoop()
 151 {
 152     /*
 153        We use a dirty hack here to disable all application windows (which we
 154        must do because otherwise the calls to wxYield() could lead to some very
 155        unexpected reentrancies in the users code) but to avoid losing
 156        focus/activation entirely when the child process terminates which would
 157        happen if we simply disabled everything using wxWindowDisabler. Indeed,
 158        remember that Windows will never activate a disabled window and when the
 159        last childs window is closed and Windows looks for a window to activate
 160        all our windows are still disabled. There is no way to enable them in
 161        time because we don't know when the childs windows are going to be
 162        closed, so the solution we use here is to keep one special tiny frame
 163        enabled all the time. Then when the child terminates it will get
 164        activated and when we close it below -- after reenabling all the other
 165        windows! -- the previously active window becomes activated again and
 166        everything is ok.
 167      */
 168     wxBeginBusyCursor();
 169
 170     // first disable all existing windows
 171     wxWindowDisabler *wd = new wxWindowDisabler;
 172
 173     // then create an "invisible" frame: it has minimal size, is positioned
 174     // (hopefully) outside the screen and doesn't appear on the taskbar
 175     wxWindow *winActive = new wxFrame
 176                     (
 177                         wxTheApp->GetTopWindow(),
 178                         wxID_ANY,
 179                         wxEmptyString,
 180                         wxPoint(32600, 32600),
 181                         wxSize(1, 1),
 182                         wxDEFAULT_FRAME_STYLE | wxFRAME_NO_TASKBAR
 183                     );
 184     winActive->Show();
 185
 186     return new ChildWaitLoopData(wd, winActive);
 187 }
 188
 189 void wxGUIAppTraits::AlwaysYield()
 190 {
 191     wxYield();
 192 }
 193
 194 void wxGUIAppTraits::AfterChildWaitLoop(void *dataOrig)
 195 {
 196     wxEndBusyCursor();
 197
 198     ChildWaitLoopData * const data = (ChildWaitLoopData *)dataOrig;
 199
 200     delete data->wd;
 201
 202     // finally delete the dummy frame and, as wd has been already destroyed and
 203     // the other windows reenabled, the activation is going to return to the
 204     // window which had had it before
 205     data->winActive->Destroy();
 206
 207     // also delete the temporary data object itself
 208     delete data;
 209 }
 210
 211 bool wxGUIAppTraits::DoMessageFromThreadWait()
 212 {
 213     // we should return false only if the app should exit, i.e. only if
 214     // Dispatch() determines that the main event loop should terminate
 215     wxEventLoop *evtLoop = wxEventLoop::GetActive();
 216     if ( !evtLoop || !evtLoop->Pending() )
 217     {
 218         // no events means no quit event
 219         return true;
 220     }
 221
 222     return evtLoop->Dispatch();
 223 }
 224
 225 DWORD wxGUIAppTraits::WaitForThread(WXHANDLE hThread)
 226 {
 227     // if we don't have a running event loop, we shouldn't wait for the
 228     // messages as we never remove them from the message queue and so we enter
 229     // an infinite loop as MsgWaitForMultipleObjects() keeps returning
 230     // WAIT_OBJECT_0 + 1
 231     if ( !wxEventLoop::GetActive() )
 232         return DoSimpleWaitForThread(hThread);
 233
 234     return ::MsgWaitForMultipleObjects
 235              (
 236                1,                   // number of objects to wait for
 237                (HANDLE *)&hThread,  // the objects
 238                false,               // wait for any objects, not all
 239                INFINITE,            // no timeout
 240                QS_ALLINPUT |        // return as soon as there are any events
 241                QS_ALLPOSTMESSAGE
 242              );
 243 }
 244
 245 wxPortId wxGUIAppTraits::GetToolkitVersion(int *majVer, int *minVer) const
 246 {
 247     OSVERSIONINFO info;
 248     wxZeroMemory(info);
 249
 250     // on Windows, the toolkit version is the same of the OS version
 251     // as Windows integrates the OS kernel with the GUI toolkit.
 252     info.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
 253     if ( ::GetVersionEx(&info) )
 254     {
 255         if ( majVer )
 256             *majVer = info.dwMajorVersion;
 257         if ( minVer )
 258             *minVer = info.dwMinorVersion;
 259     }
 260
 261 #if defined(__WXHANDHELD__) || defined(__WXWINCE__)
 262     return wxPORT_WINCE;
 263 #else
 264     return wxPORT_MSW;
 265 #endif
 266 }
 267
 268 // ===========================================================================
 269 // wxApp implementation
 270 // ===========================================================================
 271
 272 int wxApp::m_nCmdShow = SW_SHOWNORMAL;
 273
 274 // ---------------------------------------------------------------------------
 275 // wxWin macros
 276 // ---------------------------------------------------------------------------
 277
 278 IMPLEMENT_DYNAMIC_CLASS(wxApp, wxEvtHandler)
 279
 280 BEGIN_EVENT_TABLE(wxApp, wxEvtHandler)
 281     EVT_IDLE(wxApp::OnIdle)
 282     EVT_END_SESSION(wxApp::OnEndSession)
 283     EVT_QUERY_END_SESSION(wxApp::OnQueryEndSession)
 284 END_EVENT_TABLE()
 285
 286 // class to ensure that wxAppBase::CleanUp() is called if our Initialize()
 287 // fails
 288 class wxCallBaseCleanup
 289 {
 290 public:
 291     wxCallBaseCleanup(wxApp *app) : m_app(app) { }
 292     ~wxCallBaseCleanup() { if ( m_app ) m_app->wxAppBase::CleanUp(); }
 293
 294     void Dismiss() { m_app = NULL; }
 295
 296 private:
 297     wxApp *m_app;
 298 };
 299
 300 //// Initialize
 301 bool wxApp::Initialize(int& argc, wxChar **argv)
 302 {
 303     if ( !wxAppBase::Initialize(argc, argv) )
 304         return false;
 305
 306     // ensure that base cleanup is done if we return too early
 307     wxCallBaseCleanup callBaseCleanup(this);
 308
 309 #ifdef __WXWINCE__
 310     wxString tmp = GetAppName();
 311     tmp += wxT("ClassName");
 312     wxCanvasClassName = wxStrdup( tmp.c_str() );
 313     tmp += wxT("NR");
 314     wxCanvasClassNameNR = wxStrdup( tmp.c_str() );
 315     HWND hWnd = FindWindow( wxCanvasClassNameNR, NULL );
 316     if (hWnd)
 317     {
 318         SetForegroundWindow( (HWND)(((DWORD)hWnd)|0x01) );
 319         return false;
 320     }
 321 #endif
 322
 323 #if !defined(__WXMICROWIN__)
 324     InitCommonControls();
 325 #endif // !defined(__WXMICROWIN__)
 326
 327 #if defined(__SMARTPHONE__) || defined(__POCKETPC__)
 328     SHInitExtraControls();
 329 #endif
 330
 331 #ifndef __WXWINCE__
 332     // Don't show a message box if a function such as SHGetFileInfo
 333     // fails to find a device.
 334     SetErrorMode(SEM_FAILCRITICALERRORS|SEM_NOOPENFILEERRORBOX);
 335 #endif
 336
 337     wxOleInitialize();
 338
 339     RegisterWindowClasses();
 340
 341     wxWinHandleHash = new wxWinHashTable(wxKEY_INTEGER, 100);
 342
 343 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 344     wxSetKeyboardHook(true);
 345 #endif
 346
 347     callBaseCleanup.Dismiss();
 348
 349     return true;
 350 }
 351
 352 // ---------------------------------------------------------------------------
 353 // RegisterWindowClasses
 354 // ---------------------------------------------------------------------------
 355
 356 // TODO we should only register classes really used by the app. For this it
 357 //      would be enough to just delay the class registration until an attempt
 358 //      to create a window of this class is made.
 359 bool wxApp::RegisterWindowClasses()
 360 {
 361     WNDCLASS wndclass;
 362     wxZeroMemory(wndclass);
 363
 364     // for each class we register one with CS_(V|H)REDRAW style and one
 365     // without for windows created with wxNO_FULL_REDRAW_ON_REPAINT flag
 366     static const long styleNormal = CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
 367     static const long styleNoRedraw = CS_DBLCLKS;
 368
 369     // the fields which are common to all classes
 370     wndclass.lpfnWndProc   = (WNDPROC)wxWndProc;
 371     wndclass.hInstance     = wxhInstance;
 372     wndclass.hCursor       = ::LoadCursor((HINSTANCE)NULL, IDC_ARROW);
 373
 374     // register the class for all normal windows
 375     wndclass.hbrBackground = (HBRUSH)(COLOR_BTNFACE + 1);
 376     wndclass.lpszClassName = wxCanvasClassName;
 377     wndclass.style         = styleNormal;
 378
 379     if ( !RegisterClass(&wndclass) )
 380     {
 381         wxLogLastError(wxT("RegisterClass(frame)"));
 382     }
 383
 384     // "no redraw" frame
 385     wndclass.lpszClassName = wxCanvasClassNameNR;
 386     wndclass.style         = styleNoRedraw;
 387
 388     if ( !RegisterClass(&wndclass) )
 389     {
 390         wxLogLastError(wxT("RegisterClass(no redraw frame)"));
 391     }
 392
 393     // Register the MDI frame window class.
 394     wndclass.hbrBackground = (HBRUSH)NULL; // paint MDI frame ourselves
 395     wndclass.lpszClassName = wxMDIFrameClassName;
 396     wndclass.style         = styleNormal;
 397
 398     if ( !RegisterClass(&wndclass) )
 399     {
 400         wxLogLastError(wxT("RegisterClass(MDI parent)"));
 401     }
 402
 403     // "no redraw" MDI frame
 404     wndclass.lpszClassName = wxMDIFrameClassNameNoRedraw;
 405     wndclass.style         = styleNoRedraw;
 406
 407     if ( !RegisterClass(&wndclass) )
 408     {
 409         wxLogLastError(wxT("RegisterClass(no redraw MDI parent frame)"));
 410     }
 411
 412     // Register the MDI child frame window class.
 413     wndclass.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
 414     wndclass.lpszClassName = wxMDIChildFrameClassName;
 415     wndclass.style         = styleNormal;
 416
 417     if ( !RegisterClass(&wndclass) )
 418     {
 419         wxLogLastError(wxT("RegisterClass(MDI child)"));
 420     }
 421
 422     // "no redraw" MDI child frame
 423     wndclass.lpszClassName = wxMDIChildFrameClassNameNoRedraw;
 424     wndclass.style         = styleNoRedraw;
 425
 426     if ( !RegisterClass(&wndclass) )
 427     {
 428         wxLogLastError(wxT("RegisterClass(no redraw MDI child)"));
 429     }
 430
 431     return true;
 432 }
 433
 434 // ---------------------------------------------------------------------------
 435 // UnregisterWindowClasses
 436 // ---------------------------------------------------------------------------
 437
 438 bool wxApp::UnregisterWindowClasses()
 439 {
 440     bool retval = true;
 441
 442 #ifndef __WXMICROWIN__
 443     // MDI frame window class.
 444     if ( !::UnregisterClass(wxMDIFrameClassName, wxhInstance) )
 445     {
 446         wxLogLastError(wxT("UnregisterClass(MDI parent)"));
 447
 448         retval = false;
 449     }
 450
 451     // "no redraw" MDI frame
 452     if ( !::UnregisterClass(wxMDIFrameClassNameNoRedraw, wxhInstance) )
 453     {
 454         wxLogLastError(wxT("UnregisterClass(no redraw MDI parent frame)"));
 455
 456         retval = false;
 457     }
 458
 459     // MDI child frame window class.
 460     if ( !::UnregisterClass(wxMDIChildFrameClassName, wxhInstance) )
 461     {
 462         wxLogLastError(wxT("UnregisterClass(MDI child)"));
 463
 464         retval = false;
 465     }
 466
 467     // "no redraw" MDI child frame
 468     if ( !::UnregisterClass(wxMDIChildFrameClassNameNoRedraw, wxhInstance) )
 469     {
 470         wxLogLastError(wxT("UnregisterClass(no redraw MDI child)"));
 471
 472         retval = false;
 473     }
 474
 475     // canvas class name
 476     if ( !::UnregisterClass(wxCanvasClassName, wxhInstance) )
 477     {
 478         wxLogLastError(wxT("UnregisterClass(canvas)"));
 479
 480         retval = false;
 481     }
 482
 483     if ( !::UnregisterClass(wxCanvasClassNameNR, wxhInstance) )
 484     {
 485         wxLogLastError(wxT("UnregisterClass(no redraw canvas)"));
 486
 487         retval = false;
 488     }
 489 #endif // __WXMICROWIN__
 490
 491     return retval;
 492 }
 493
 494 void wxApp::CleanUp()
 495 {
 496     // all objects pending for deletion must be deleted first, otherwise we
 497     // would crash when they use wxWinHandleHash (and UnregisterWindowClasses()
 498     // call wouldn't succeed as long as any windows still exist), so call the
 499     // base class method first and only then do our clean up
 500     wxAppBase::CleanUp();
 501
 502 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 503     wxSetKeyboardHook(false);
 504 #endif
 505
 506     wxOleUninitialize();
 507
 508     // for an EXE the classes are unregistered when it terminates but DLL may
 509     // be loaded several times (load/unload/load) into the same process in
 510     // which case the registration will fail after the first time if we don't
 511     // unregister the classes now
 512     UnregisterWindowClasses();
 513
 514     delete wxWinHandleHash;
 515     wxWinHandleHash = NULL;
 516
 517 #ifdef __WXWINCE__
 518     free( wxCanvasClassName );
 519     free( wxCanvasClassNameNR );
 520 #endif
 521 }
 522
 523 // ----------------------------------------------------------------------------
 524 // wxApp ctor/dtor
 525 // ----------------------------------------------------------------------------
 526
 527 wxApp::wxApp()
 528 {
 529     m_printMode = wxPRINT_WINDOWS;
 530 }
 531
 532 wxApp::~wxApp()
 533 {
 534 }
 535
 536 // ----------------------------------------------------------------------------
 537 // wxApp idle handling
 538 // ----------------------------------------------------------------------------
 539
 540 void wxApp::OnIdle(wxIdleEvent& event)
 541 {
 542     wxAppBase::OnIdle(event);
 543
 544 #if wxUSE_DC_CACHEING
 545     // automated DC cache management: clear the cached DCs and bitmap
 546     // if it's likely that the app has finished with them, that is, we
 547     // get an idle event and we're not dragging anything.
 548     if (!::GetKeyState(MK_LBUTTON) && !::GetKeyState(MK_MBUTTON) && !::GetKeyState(MK_RBUTTON))
 549         wxDC::ClearCache();
 550 #endif // wxUSE_DC_CACHEING
 551 }
 552
 553 void wxApp::WakeUpIdle()
 554 {
 555     // Send the top window a dummy message so idle handler processing will
 556     // start up again.  Doing it this way ensures that the idle handler
 557     // wakes up in the right thread (see also wxWakeUpMainThread() which does
 558     // the same for the main app thread only)
 559     wxWindow *topWindow = wxTheApp->GetTopWindow();
 560     if ( topWindow )
 561     {
 562         if ( !::PostMessage(GetHwndOf(topWindow), WM_NULL, 0, 0) )
 563         {
 564             // should never happen
 565             wxLogLastError(wxT("PostMessage(WM_NULL)"));
 566         }
 567     }
 568 }
 569
 570 // ----------------------------------------------------------------------------
 571 // other wxApp event hanlders
 572 // ----------------------------------------------------------------------------
 573
 574 void wxApp::OnEndSession(wxCloseEvent& WXUNUSED(event))
 575 {
 576     if (GetTopWindow())
 577         GetTopWindow()->Close(true);
 578 }
 579
 580 // Default behaviour: close the application with prompts. The
 581 // user can veto the close, and therefore the end session.
 582 void wxApp::OnQueryEndSession(wxCloseEvent& event)
 583 {
 584     if (GetTopWindow())
 585     {
 586         if (!GetTopWindow()->Close(!event.CanVeto()))
 587             event.Veto(true);
 588     }
 589 }
 590
 591 // ----------------------------------------------------------------------------
 592 // miscellaneous
 593 // ----------------------------------------------------------------------------
 594
 595 /* static */
 596 int wxApp::GetComCtl32Version()
 597 {
 598 #if defined(__WXMICROWIN__) || defined(__WXWINCE__)
 599     return 0;
 600 #else
 601     // cache the result
 602     //
 603     // NB: this is MT-ok as in the worst case we'd compute s_verComCtl32 twice,
 604     //     but as its value should be the same both times it doesn't matter
 605     static int s_verComCtl32 = -1;
 606
 607     if ( s_verComCtl32 == -1 )
 608     {
 609         // initally assume no comctl32.dll at all
 610         s_verComCtl32 = 0;
 611
 612         // we're prepared to handle the errors
 613         wxLogNull noLog;
 614
 615 #if wxUSE_DYNLIB_CLASS
 616         // do we have it?
 617         wxDynamicLibrary dllComCtl32(_T("comctl32.dll"), wxDL_VERBATIM);
 618
 619         // if so, then we can check for the version
 620         if ( dllComCtl32.IsLoaded() )
 621         {
 622             // now check if the function is available during run-time
 623             wxDYNLIB_FUNCTION( DLLGETVERSIONPROC, DllGetVersion, dllComCtl32 );
 624             if ( pfnDllGetVersion )
 625             {
 626                 DLLVERSIONINFO dvi;
 627                 dvi.cbSize = sizeof(dvi);
 628
 629                 HRESULT hr = (*pfnDllGetVersion)(&dvi);
 630                 if ( FAILED(hr) )
 631                 {
 632                     wxLogApiError(_T("DllGetVersion"), hr);
 633                 }
 634                 else
 635                 {
 636                     // this is incompatible with _WIN32_IE values, but
 637                     // compatible with the other values returned by
 638                     // GetComCtl32Version()
 639                     s_verComCtl32 = 100*dvi.dwMajorVersion +
 640                                         dvi.dwMinorVersion;
 641                 }
 642             }
 643
 644             // if DllGetVersion() is unavailable either during compile or
 645             // run-time, try to guess the version otherwise
 646             if ( !s_verComCtl32 )
 647             {
 648                 // InitCommonControlsEx is unique to 4.70 and later
 649                 void *pfn = dllComCtl32.GetSymbol(_T("InitCommonControlsEx"));
 650                 if ( !pfn )
 651                 {
 652                     // not found, must be 4.00
 653                     s_verComCtl32 = 400;
 654                 }
 655                 else // 4.70+
 656                 {
 657                     // many symbols appeared in comctl32 4.71, could use any of
 658                     // them except may be DllInstall()
 659                     pfn = dllComCtl32.GetSymbol(_T("InitializeFlatSB"));
 660                     if ( !pfn )
 661                     {
 662                         // not found, must be 4.70
 663                         s_verComCtl32 = 470;
 664                     }
 665                     else
 666                     {
 667                         // found, must be 4.71 or later
 668                         s_verComCtl32 = 471;
 669                     }
 670                 }
 671             }
 672         }
 673 #endif
 674     }
 675
 676     return s_verComCtl32;
 677 #endif // Microwin/!Microwin
 678 }
 679
 680 // Yield to incoming messages
 681
 682 bool wxApp::Yield(bool onlyIfNeeded)
 683 {
 684     // MT-FIXME
 685     static bool s_inYield = false;
 686
 687 #if wxUSE_LOG
 688     // disable log flushing from here because a call to wxYield() shouldn't
 689     // normally result in message boxes popping up &c
 690     wxLog::Suspend();
 691 #endif // wxUSE_LOG
 692
 693     if ( s_inYield )
 694     {
 695         if ( !onlyIfNeeded )
 696         {
 697             wxFAIL_MSG( wxT("wxYield called recursively" ) );
 698         }
 699
 700         return false;
 701     }
 702
 703     s_inYield = true;
 704
 705     // we don't want to process WM_QUIT from here - it should be processed in
 706     // the main event loop in order to stop it
 707     MSG msg;
 708     while ( PeekMessage(&msg, (HWND)0, 0, 0, PM_NOREMOVE) &&
 709             msg.message != WM_QUIT )
 710     {
 711 #if wxUSE_THREADS
 712         wxMutexGuiLeaveOrEnter();
 713 #endif // wxUSE_THREADS
 714
 715         if ( !wxTheApp->Dispatch() )
 716             break;
 717     }
 718
 719     // if there are pending events, we must process them.
 720     ProcessPendingEvents();
 721
 722 #if wxUSE_LOG
 723     // let the logs be flashed again
 724     wxLog::Resume();
 725 #endif // wxUSE_LOG
 726
 727     s_inYield = false;
 728
 729     return true;
 730 }
 731
 732 #if wxUSE_EXCEPTIONS
 733
 734 // ----------------------------------------------------------------------------
 735 // exception handling
 736 // ----------------------------------------------------------------------------
 737
 738 bool wxApp::OnExceptionInMainLoop()
 739 {
 740     // ask the user about what to do: use the Win32 API function here as it
 741     // could be dangerous to use any wxWidgets code in this state
 742     switch (
 743             ::MessageBox
 744               (
 745                 NULL,
 746                 _T("An unhandled exception occurred. Press \"Abort\" to \
 747 terminate the program,\r\n\
 748 \"Retry\" to exit the program normally and \"Ignore\" to try to continue."),
 749                 _T("Unhandled exception"),
 750                 MB_ABORTRETRYIGNORE |
 751                 MB_ICONERROR|
 752                 MB_TASKMODAL
 753               )
 754            )
 755     {
 756         case IDABORT:
 757             throw;
 758
 759         default:
 760             wxFAIL_MSG( _T("unexpected MessageBox() return code") );
 761             // fall through
 762
 763         case IDRETRY:
 764             return false;
 765
 766         case IDIGNORE:
 767             return true;
 768     }
 769 }
 770
 771 #endif // wxUSE_EXCEPTIONS