src/msw/app.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        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 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  21     #pragma implementation "app.h"
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #if defined(__BORLANDC__)
  28     #pragma hdrstop
  29 #endif
  30
  31 #ifndef WX_PRECOMP
  32     #include "wx/frame.h"
  33     #include "wx/app.h"
  34     #include "wx/utils.h"
  35     #include "wx/gdicmn.h"
  36     #include "wx/pen.h"
  37     #include "wx/brush.h"
  38     #include "wx/cursor.h"
  39     #include "wx/icon.h"
  40     #include "wx/palette.h"
  41     #include "wx/dc.h"
  42     #include "wx/dialog.h"
  43     #include "wx/msgdlg.h"
  44     #include "wx/intl.h"
  45     #include "wx/dynarray.h"
  46     #include "wx/wxchar.h"
  47     #include "wx/icon.h"
  48     #include "wx/log.h"
  49 #endif
  50
  51 #include "wx/apptrait.h"
  52 #include "wx/filename.h"
  53 #include "wx/module.h"
  54 #include "wx/dynlib.h"
  55
  56 #include "wx/msw/private.h"
  57
  58 #if wxUSE_TOOLTIPS
  59     #include "wx/tooltip.h"
  60 #endif // wxUSE_TOOLTIPS
  61
  62 // OLE is used for drag-and-drop, clipboard, OLE Automation..., but some
  63 // compilers don't support it (missing headers, libs, ...)
  64 #if defined(__GNUWIN32_OLD__) || defined(__SYMANTEC__) || defined(__SALFORDC__)
  65     #undef wxUSE_OLE
  66
  67     #define  wxUSE_OLE 0
  68 #endif // broken compilers
  69
  70 #if wxUSE_OLE
  71     #include <ole2.h>
  72 #endif
  73
  74 #include <string.h>
  75 #include <ctype.h>
  76
  77 #include "wx/msw/wrapcctl.h"
  78
  79 // For MB_TASKMODAL
  80 #ifdef __WXWINCE__
  81 #include "wx/msw/wince/missing.h"
  82 #endif
  83
  84 #if (!defined(__MINGW32__) || wxCHECK_W32API_VERSION( 2, 0 )) && \
  85     !defined(__CYGWIN__) && !defined(__DIGITALMARS__) && !defined(__WXWINCE__) && \
  86     (!defined(_MSC_VER) || (_MSC_VER > 1100))
  87     #include <shlwapi.h>
  88 #endif
  89
  90 // ---------------------------------------------------------------------------
  91 // global variables
  92 // ---------------------------------------------------------------------------
  93
  94 extern wxList WXDLLEXPORT wxPendingDelete;
  95
  96 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
  97 extern void wxSetKeyboardHook(bool doIt);
  98 #endif
  99
 100 // NB: all "NoRedraw" classes must have the same names as the "normal" classes
 101 //     with NR suffix - wxWindow::MSWCreate() supposes this
 102 #ifdef __WXWINCE__
 103       wxChar *wxCanvasClassName;
 104       wxChar *wxCanvasClassNameNR;
 105 #else
 106 const wxChar *wxCanvasClassName        = wxT("wxWindowClass");
 107 const wxChar *wxCanvasClassNameNR      = wxT("wxWindowClassNR");
 108 #endif
 109 const wxChar *wxMDIFrameClassName      = wxT("wxMDIFrameClass");
 110 const wxChar *wxMDIFrameClassNameNoRedraw = wxT("wxMDIFrameClassNR");
 111 const wxChar *wxMDIChildFrameClassName = wxT("wxMDIChildFrameClass");
 112 const wxChar *wxMDIChildFrameClassNameNoRedraw = wxT("wxMDIChildFrameClassNR");
 113
 114 HBRUSH wxDisableButtonBrush = (HBRUSH) 0;
 115
 116 // ----------------------------------------------------------------------------
 117 // private functions
 118 // ----------------------------------------------------------------------------
 119
 120 LRESULT WXDLLEXPORT APIENTRY wxWndProc(HWND, UINT, WPARAM, LPARAM);
 121
 122 // ===========================================================================
 123 // wxGUIAppTraits implementation
 124 // ===========================================================================
 125
 126 // private class which we use to pass parameters from BeforeChildWaitLoop() to
 127 // AfterChildWaitLoop()
 128 struct ChildWaitLoopData
 129 {
 130     ChildWaitLoopData(wxWindowDisabler *wd_, wxWindow *winActive_)
 131     {
 132         wd = wd_;
 133         winActive = winActive_;
 134     }
 135
 136     wxWindowDisabler *wd;
 137     wxWindow *winActive;
 138 };
 139
 140 void *wxGUIAppTraits::BeforeChildWaitLoop()
 141 {
 142     /*
 143        We use a dirty hack here to disable all application windows (which we
 144        must do because otherwise the calls to wxYield() could lead to some very
 145        unexpected reentrancies in the users code) but to avoid losing
 146        focus/activation entirely when the child process terminates which would
 147        happen if we simply disabled everything using wxWindowDisabler. Indeed,
 148        remember that Windows will never activate a disabled window and when the
 149        last childs window is closed and Windows looks for a window to activate
 150        all our windows are still disabled. There is no way to enable them in
 151        time because we don't know when the childs windows are going to be
 152        closed, so the solution we use here is to keep one special tiny frame
 153        enabled all the time. Then when the child terminates it will get
 154        activated and when we close it below -- after reenabling all the other
 155        windows! -- the previously active window becomes activated again and
 156        everything is ok.
 157      */
 158     wxBeginBusyCursor();
 159
 160     // first disable all existing windows
 161     wxWindowDisabler *wd = new wxWindowDisabler;
 162
 163     // then create an "invisible" frame: it has minimal size, is positioned
 164     // (hopefully) outside the screen and doesn't appear on the taskbar
 165     wxWindow *winActive = new wxFrame
 166                     (
 167                         wxTheApp->GetTopWindow(),
 168                         wxID_ANY,
 169                         wxEmptyString,
 170                         wxPoint(32600, 32600),
 171                         wxSize(1, 1),
 172                         wxDEFAULT_FRAME_STYLE | wxFRAME_NO_TASKBAR
 173                     );
 174     winActive->Show();
 175
 176     return new ChildWaitLoopData(wd, winActive);
 177 }
 178
 179 void wxGUIAppTraits::AlwaysYield()
 180 {
 181     wxYield();
 182 }
 183
 184 void wxGUIAppTraits::AfterChildWaitLoop(void *dataOrig)
 185 {
 186     wxEndBusyCursor();
 187
 188     const ChildWaitLoopData * const data = (ChildWaitLoopData *)dataOrig;
 189
 190     delete data->wd;
 191
 192     // finally delete the dummy frame and, as wd has been already destroyed and
 193     // the other windows reenabled, the activation is going to return to the
 194     // window which had had it before
 195     data->winActive->Destroy();
 196 }
 197
 198 bool wxGUIAppTraits::DoMessageFromThreadWait()
 199 {
 200     // we should return false only if the app should exit, i.e. only if
 201     // Dispatch() determines that the main event loop should terminate
 202     return !wxTheApp || wxTheApp->Dispatch();
 203 }
 204
 205 wxToolkitInfo& wxGUIAppTraits::GetToolkitInfo()
 206 {
 207     static wxToolkitInfo info;
 208     wxToolkitInfo& baseInfo = wxAppTraits::GetToolkitInfo();
 209     info.versionMajor = baseInfo.versionMajor;
 210     info.versionMinor = baseInfo.versionMinor;
 211     info.os = baseInfo.os;
 212     info.shortName = _T("msw");
 213     info.name = _T("wxMSW");
 214 #ifdef __WXUNIVERSAL__
 215     info.shortName << _T("univ");
 216     info.name << _T("/wxUniversal");
 217 #endif
 218     return info;
 219 }
 220
 221 // ===========================================================================
 222 // wxApp implementation
 223 // ===========================================================================
 224
 225 int wxApp::m_nCmdShow = SW_SHOWNORMAL;
 226
 227 // ---------------------------------------------------------------------------
 228 // wxWin macros
 229 // ---------------------------------------------------------------------------
 230
 231 IMPLEMENT_DYNAMIC_CLASS(wxApp, wxEvtHandler)
 232
 233 BEGIN_EVENT_TABLE(wxApp, wxEvtHandler)
 234     EVT_IDLE(wxApp::OnIdle)
 235     EVT_END_SESSION(wxApp::OnEndSession)
 236     EVT_QUERY_END_SESSION(wxApp::OnQueryEndSession)
 237 END_EVENT_TABLE()
 238
 239 // class to ensure that wxAppBase::CleanUp() is called if our Initialize()
 240 // fails
 241 class wxCallBaseCleanup
 242 {
 243 public:
 244     wxCallBaseCleanup(wxApp *app) : m_app(app) { }
 245     ~wxCallBaseCleanup() { if ( m_app ) m_app->wxAppBase::CleanUp(); }
 246
 247     void Dismiss() { m_app = NULL; }
 248
 249 private:
 250     wxApp *m_app;
 251 };
 252
 253 //// Initialize
 254 bool wxApp::Initialize(int& argc, wxChar **argv)
 255 {
 256     if ( !wxAppBase::Initialize(argc, argv) )
 257         return false;
 258
 259     // ensure that base cleanup is done if we return too early
 260     wxCallBaseCleanup callBaseCleanup(this);
 261
 262 #ifdef __WXWINCE__
 263     wxString tmp = GetAppName();
 264     tmp += wxT("ClassName");
 265     wxCanvasClassName = wxStrdup( tmp.c_str() );
 266     tmp += wxT("NR");
 267     wxCanvasClassNameNR = wxStrdup( tmp.c_str() );
 268     HWND hWnd = FindWindow( wxCanvasClassNameNR, NULL );
 269     if (hWnd)
 270     {
 271         SetForegroundWindow( (HWND)(((DWORD)hWnd)|0x01) );
 272         return false;
 273     }
 274 #endif
 275
 276     // the first thing to do is to check if we're trying to run an Unicode
 277     // program under Win9x w/o MSLU emulation layer - if so, abort right now
 278     // as it has no chance to work
 279 #if wxUSE_UNICODE && !wxUSE_UNICODE_MSLU
 280     if ( wxGetOsVersion() != wxWINDOWS_NT && wxGetOsVersion() != wxWINDOWS_CE )
 281     {
 282         // note that we can use MessageBoxW() as it's implemented even under
 283         // Win9x - OTOH, we can't use wxGetTranslation() because the file APIs
 284         // used by wxLocale are not
 285         ::MessageBox
 286         (
 287          NULL,
 288          _T("This program uses Unicode and requires Windows NT/2000/XP/CE.\nProgram aborted."),
 289          _T("wxWidgets Fatal Error"),
 290          MB_ICONERROR | MB_OK
 291         );
 292
 293         return false;
 294     }
 295 #endif // wxUSE_UNICODE && !wxUSE_UNICODE_MSLU
 296
 297 #if defined(__WIN95__) && !defined(__WXMICROWIN__)
 298     InitCommonControls();
 299 #endif // __WIN95__
 300
 301 #if wxUSE_OLE || wxUSE_DRAG_AND_DROP
 302
 303 #if wxUSE_OLE
 304     // we need to initialize OLE library
 305 #ifdef __WXWINCE__
 306     if ( FAILED(::CoInitializeEx(NULL, COINIT_MULTITHREADED)) )
 307         wxLogError(_("Cannot initialize OLE"));
 308 #else
 309     if ( FAILED(::OleInitialize(NULL)) )
 310         wxLogError(_("Cannot initialize OLE"));
 311 #endif
 312 #endif
 313
 314 #endif // wxUSE_OLE
 315
 316 #if wxUSE_CTL3D
 317     if (!Ctl3dRegister(wxhInstance))
 318         wxLogError(wxT("Cannot register CTL3D"));
 319
 320     Ctl3dAutoSubclass(wxhInstance);
 321 #endif // wxUSE_CTL3D
 322
 323     RegisterWindowClasses();
 324
 325 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 326     // Create the brush for disabling bitmap buttons
 327     LOGBRUSH lb;
 328     lb.lbStyle = BS_PATTERN;
 329     lb.lbColor = 0;
 330     lb.lbHatch = (int)LoadBitmap( wxhInstance, wxT("wxDISABLE_BUTTON_BITMAP") );
 331     if ( lb.lbHatch )
 332     {
 333         wxDisableButtonBrush = ::CreateBrushIndirect( &lb );
 334         ::DeleteObject( (HGDIOBJ)lb.lbHatch );
 335     }
 336     //else: wxWidgets resources are probably not linked in
 337 #endif // !__WXMICROWIN__ && !__WXWINCE__
 338
 339 #if wxUSE_PENWINDOWS
 340     wxRegisterPenWin();
 341 #endif
 342
 343     wxWinHandleHash = new wxWinHashTable(wxKEY_INTEGER, 100);
 344
 345 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 346     wxSetKeyboardHook(true);
 347 #endif
 348
 349     callBaseCleanup.Dismiss();
 350
 351     return true;
 352 }
 353
 354 // ---------------------------------------------------------------------------
 355 // RegisterWindowClasses
 356 // ---------------------------------------------------------------------------
 357
 358 // TODO we should only register classes really used by the app. For this it
 359 //      would be enough to just delay the class registration until an attempt
 360 //      to create a window of this class is made.
 361 bool wxApp::RegisterWindowClasses()
 362 {
 363     WNDCLASS wndclass;
 364     wxZeroMemory(wndclass);
 365
 366     // for each class we register one with CS_(V|H)REDRAW style and one
 367     // without for windows created with wxNO_FULL_REDRAW_ON_REPAINT flag
 368     static const long styleNormal = CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;
 369     static const long styleNoRedraw = CS_DBLCLKS;
 370
 371     // the fields which are common to all classes
 372     wndclass.lpfnWndProc   = (WNDPROC)wxWndProc;
 373     wndclass.hInstance     = wxhInstance;
 374     wndclass.hCursor       = ::LoadCursor((HINSTANCE)NULL, IDC_ARROW);
 375
 376     // Register the frame window class.
 377     wndclass.hbrBackground = (HBRUSH)(COLOR_APPWORKSPACE + 1);
 378     wndclass.lpszClassName = wxCanvasClassName;
 379     wndclass.style         = styleNormal;
 380
 381     if ( !RegisterClass(&wndclass) )
 382     {
 383         wxLogLastError(wxT("RegisterClass(frame)"));
 384     }
 385
 386     // "no redraw" frame
 387     wndclass.lpszClassName = wxCanvasClassNameNR;
 388     wndclass.style         = styleNoRedraw;
 389
 390     if ( !RegisterClass(&wndclass) )
 391     {
 392         wxLogLastError(wxT("RegisterClass(no redraw frame)"));
 393     }
 394
 395     // Register the MDI frame window class.
 396     wndclass.hbrBackground = (HBRUSH)NULL; // paint MDI frame ourselves
 397     wndclass.lpszClassName = wxMDIFrameClassName;
 398     wndclass.style         = styleNormal;
 399
 400     if ( !RegisterClass(&wndclass) )
 401     {
 402         wxLogLastError(wxT("RegisterClass(MDI parent)"));
 403     }
 404
 405     // "no redraw" MDI frame
 406     wndclass.lpszClassName = wxMDIFrameClassNameNoRedraw;
 407     wndclass.style         = styleNoRedraw;
 408
 409     if ( !RegisterClass(&wndclass) )
 410     {
 411         wxLogLastError(wxT("RegisterClass(no redraw MDI parent frame)"));
 412     }
 413
 414     // Register the MDI child frame window class.
 415     wndclass.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
 416     wndclass.lpszClassName = wxMDIChildFrameClassName;
 417     wndclass.style         = styleNormal;
 418
 419     if ( !RegisterClass(&wndclass) )
 420     {
 421         wxLogLastError(wxT("RegisterClass(MDI child)"));
 422     }
 423
 424     // "no redraw" MDI child frame
 425     wndclass.lpszClassName = wxMDIChildFrameClassNameNoRedraw;
 426     wndclass.style         = styleNoRedraw;
 427
 428     if ( !RegisterClass(&wndclass) )
 429     {
 430         wxLogLastError(wxT("RegisterClass(no redraw MDI child)"));
 431     }
 432
 433     return true;
 434 }
 435
 436 // ---------------------------------------------------------------------------
 437 // UnregisterWindowClasses
 438 // ---------------------------------------------------------------------------
 439
 440 bool wxApp::UnregisterWindowClasses()
 441 {
 442     bool retval = true;
 443
 444 #ifndef __WXMICROWIN__
 445     // MDI frame window class.
 446     if ( !::UnregisterClass(wxMDIFrameClassName, wxhInstance) )
 447     {
 448         wxLogLastError(wxT("UnregisterClass(MDI parent)"));
 449
 450         retval = false;
 451     }
 452
 453     // "no redraw" MDI frame
 454     if ( !::UnregisterClass(wxMDIFrameClassNameNoRedraw, wxhInstance) )
 455     {
 456         wxLogLastError(wxT("UnregisterClass(no redraw MDI parent frame)"));
 457
 458         retval = false;
 459     }
 460
 461     // MDI child frame window class.
 462     if ( !::UnregisterClass(wxMDIChildFrameClassName, wxhInstance) )
 463     {
 464         wxLogLastError(wxT("UnregisterClass(MDI child)"));
 465
 466         retval = false;
 467     }
 468
 469     // "no redraw" MDI child frame
 470     if ( !::UnregisterClass(wxMDIChildFrameClassNameNoRedraw, wxhInstance) )
 471     {
 472         wxLogLastError(wxT("UnregisterClass(no redraw MDI child)"));
 473
 474         retval = false;
 475     }
 476
 477     // canvas class name
 478     if ( !::UnregisterClass(wxCanvasClassName, wxhInstance) )
 479     {
 480         wxLogLastError(wxT("UnregisterClass(canvas)"));
 481
 482         retval = false;
 483     }
 484
 485     if ( !::UnregisterClass(wxCanvasClassNameNR, wxhInstance) )
 486     {
 487         wxLogLastError(wxT("UnregisterClass(no redraw canvas)"));
 488
 489         retval = false;
 490     }
 491 #endif // __WXMICROWIN__
 492
 493     return retval;
 494 }
 495
 496 void wxApp::CleanUp()
 497 {
 498     // all objects pending for deletion must be deleted first, otherwise we
 499     // would crash when they use wxWinHandleHash (and UnregisterWindowClasses()
 500     // call wouldn't succeed as long as any windows still exist), so call the
 501     // base class method first and only then do our clean up
 502     wxAppBase::CleanUp();
 503
 504 #if !defined(__WXMICROWIN__) && !defined(__WXWINCE__)
 505     wxSetKeyboardHook(false);
 506 #endif
 507
 508 #if wxUSE_PENWINDOWS
 509     wxCleanUpPenWin();
 510 #endif
 511
 512     if ( wxDisableButtonBrush )
 513         ::DeleteObject( wxDisableButtonBrush );
 514
 515 #if wxUSE_OLE
 516 #ifdef __WXWINCE__
 517     ::CoUninitialize();
 518 #else
 519     ::OleUninitialize();
 520 #endif
 521 #endif
 522
 523     // for an EXE the classes are unregistered when it terminates but DLL may
 524     // be loaded several times (load/unload/load) into the same process in
 525     // which case the registration will fail after the first time if we don't
 526     // unregister the classes now
 527     UnregisterWindowClasses();
 528
 529 #if wxUSE_CTL3D
 530     Ctl3dUnregister(wxhInstance);
 531 #endif
 532
 533     delete wxWinHandleHash;
 534     wxWinHandleHash = NULL;
 535
 536 #ifdef __WXWINCE__
 537     free( wxCanvasClassName );
 538     free( wxCanvasClassNameNR );
 539 #endif
 540 }
 541
 542 // ----------------------------------------------------------------------------
 543 // wxApp ctor/dtor
 544 // ----------------------------------------------------------------------------
 545
 546 wxApp::wxApp()
 547 {
 548     m_printMode = wxPRINT_WINDOWS;
 549 }
 550
 551 wxApp::~wxApp()
 552 {
 553     // our cmd line arguments are allocated inside wxEntry(HINSTANCE), they
 554     // don't come from main(), so we have to free them
 555
 556     while ( argc )
 557     {
 558         // m_argv elements were allocated by wxStrdup()
 559         free(argv[--argc]);
 560     }
 561
 562     // but m_argv itself -- using new[]
 563     delete [] argv;
 564 }
 565
 566 // ----------------------------------------------------------------------------
 567 // wxApp idle handling
 568 // ----------------------------------------------------------------------------
 569
 570 void wxApp::OnIdle(wxIdleEvent& event)
 571 {
 572     wxAppBase::OnIdle(event);
 573
 574 #if wxUSE_DC_CACHEING
 575     // automated DC cache management: clear the cached DCs and bitmap
 576     // if it's likely that the app has finished with them, that is, we
 577     // get an idle event and we're not dragging anything.
 578     if (!::GetKeyState(MK_LBUTTON) && !::GetKeyState(MK_MBUTTON) && !::GetKeyState(MK_RBUTTON))
 579         wxDC::ClearCache();
 580 #endif // wxUSE_DC_CACHEING
 581 }
 582
 583 void wxApp::WakeUpIdle()
 584 {
 585     // Send the top window a dummy message so idle handler processing will
 586     // start up again.  Doing it this way ensures that the idle handler
 587     // wakes up in the right thread (see also wxWakeUpMainThread() which does
 588     // the same for the main app thread only)
 589     wxWindow *topWindow = wxTheApp->GetTopWindow();
 590     if ( topWindow )
 591     {
 592         if ( !::PostMessage(GetHwndOf(topWindow), WM_NULL, 0, 0) )
 593         {
 594             // should never happen
 595             wxLogLastError(wxT("PostMessage(WM_NULL)"));
 596         }
 597     }
 598 }
 599
 600 // ----------------------------------------------------------------------------
 601 // other wxApp event hanlders
 602 // ----------------------------------------------------------------------------
 603
 604 void wxApp::OnEndSession(wxCloseEvent& WXUNUSED(event))
 605 {
 606     if (GetTopWindow())
 607         GetTopWindow()->Close(true);
 608 }
 609
 610 // Default behaviour: close the application with prompts. The
 611 // user can veto the close, and therefore the end session.
 612 void wxApp::OnQueryEndSession(wxCloseEvent& event)
 613 {
 614     if (GetTopWindow())
 615     {
 616         if (!GetTopWindow()->Close(!event.CanVeto()))
 617             event.Veto(true);
 618     }
 619 }
 620
 621 // ----------------------------------------------------------------------------
 622 // miscellaneous
 623 // ----------------------------------------------------------------------------
 624
 625 /* static */
 626 int wxApp::GetComCtl32Version()
 627 {
 628 #if defined(__WXMICROWIN__) || defined(__WXWINCE__)
 629     return 0;
 630 #else
 631     // cache the result
 632     //
 633     // NB: this is MT-ok as in the worst case we'd compute s_verComCtl32 twice,
 634     //     but as its value should be the same both times it doesn't matter
 635     static int s_verComCtl32 = -1;
 636
 637     if ( s_verComCtl32 == -1 )
 638     {
 639         // initally assume no comctl32.dll at all
 640         s_verComCtl32 = 0;
 641
 642         // we're prepared to handle the errors
 643         wxLogNull noLog;
 644
 645         // do we have it?
 646         wxDynamicLibrary dllComCtl32(_T("comctl32.dll"), wxDL_VERBATIM);
 647
 648         // if so, then we can check for the version
 649         if ( dllComCtl32.IsLoaded() )
 650         {
 651 #ifdef DLLVER_PLATFORM_WINDOWS
 652             // try to use DllGetVersion() if available in _headers_
 653             wxDYNLIB_FUNCTION( DLLGETVERSIONPROC, DllGetVersion, dllComCtl32 );
 654             if ( pfnDllGetVersion )
 655             {
 656                 DLLVERSIONINFO dvi;
 657                 dvi.cbSize = sizeof(dvi);
 658
 659                 HRESULT hr = (*pfnDllGetVersion)(&dvi);
 660                 if ( FAILED(hr) )
 661                 {
 662                     wxLogApiError(_T("DllGetVersion"), hr);
 663                 }
 664                 else
 665                 {
 666                     // this is incompatible with _WIN32_IE values, but
 667                     // compatible with the other values returned by
 668                     // GetComCtl32Version()
 669                     s_verComCtl32 = 100*dvi.dwMajorVersion +
 670                                         dvi.dwMinorVersion;
 671                 }
 672             }
 673 #endif
 674
 675             // if DllGetVersion() is unavailable either during compile or
 676             // run-time, try to guess the version otherwise
 677             if ( !s_verComCtl32 )
 678             {
 679                 // InitCommonControlsEx is unique to 4.70 and later
 680                 void *pfn = dllComCtl32.GetSymbol(_T("InitCommonControlsEx"));
 681                 if ( !pfn )
 682                 {
 683                     // not found, must be 4.00
 684                     s_verComCtl32 = 400;
 685                 }
 686                 else // 4.70+
 687                 {
 688                     // many symbols appeared in comctl32 4.71, could use any of
 689                     // them except may be DllInstall()
 690                     pfn = dllComCtl32.GetSymbol(_T("InitializeFlatSB"));
 691                     if ( !pfn )
 692                     {
 693                         // not found, must be 4.70
 694                         s_verComCtl32 = 470;
 695                     }
 696                     else
 697                     {
 698                         // found, must be 4.71 or later
 699                         s_verComCtl32 = 471;
 700                     }
 701                 }
 702             }
 703         }
 704     }
 705
 706     return s_verComCtl32;
 707 #endif // Microwin/!Microwin
 708 }
 709
 710 // Yield to incoming messages
 711
 712 bool wxApp::Yield(bool onlyIfNeeded)
 713 {
 714     // MT-FIXME
 715     static bool s_inYield = false;
 716
 717 #if wxUSE_LOG
 718     // disable log flushing from here because a call to wxYield() shouldn't
 719     // normally result in message boxes popping up &c
 720     wxLog::Suspend();
 721 #endif // wxUSE_LOG
 722
 723     if ( s_inYield )
 724     {
 725         if ( !onlyIfNeeded )
 726         {
 727             wxFAIL_MSG( wxT("wxYield called recursively" ) );
 728         }
 729
 730         return false;
 731     }
 732
 733     s_inYield = true;
 734
 735     // we don't want to process WM_QUIT from here - it should be processed in
 736     // the main event loop in order to stop it
 737     MSG msg;
 738     while ( PeekMessage(&msg, (HWND)0, 0, 0, PM_NOREMOVE) &&
 739             msg.message != WM_QUIT )
 740     {
 741 #if wxUSE_THREADS
 742         wxMutexGuiLeaveOrEnter();
 743 #endif // wxUSE_THREADS
 744
 745         if ( !wxTheApp->Dispatch() )
 746             break;
 747     }
 748
 749     // if there are pending events, we must process them.
 750     ProcessPendingEvents();
 751
 752 #if wxUSE_LOG
 753     // let the logs be flashed again
 754     wxLog::Resume();
 755 #endif // wxUSE_LOG
 756
 757     s_inYield = false;
 758
 759     return true;
 760 }
 761
 762 #if wxUSE_EXCEPTIONS
 763
 764 // ----------------------------------------------------------------------------
 765 // exception handling
 766 // ----------------------------------------------------------------------------
 767
 768 bool wxApp::OnExceptionInMainLoop()
 769 {
 770     // ask the user about what to do: use the Win32 API function here as it
 771     // could be dangerous to use any wxWidgets code in this state
 772     switch (
 773             ::MessageBox
 774               (
 775                 NULL,
 776                 _T("An unhandled exception occurred. Press \"Abort\" to \
 777 terminate the program,\r\n\
 778 \"Retry\" to exit the program normally and \"Ignore\" to try to continue."),
 779                 _T("Unhandled exception"),
 780                 MB_ABORTRETRYIGNORE |
 781                 MB_ICONERROR|
 782                 MB_TASKMODAL
 783               )
 784            )
 785     {
 786         case IDABORT:
 787             throw;
 788
 789         default:
 790             wxFAIL_MSG( _T("unexpected MessageBox() return code") );
 791             // fall through
 792
 793         case IDRETRY:
 794             return false;
 795
 796         case IDIGNORE:
 797             return true;
 798     }
 799 }
 800
 801 #endif // wxUSE_EXCEPTIONS