src/msw/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/evtloop.cpp
   3 // Purpose:     implements wxEventLoop for MSW
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     01.06.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // License:     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 #ifdef __BORLANDC__
  24     #pragma hdrstop
  25 #endif
  26
  27 #ifndef WX_PRECOMP
  28     #if wxUSE_GUI
  29         #include "wx/window.h"
  30     #endif
  31     #include "wx/app.h"
  32 #endif //WX_PRECOMP
  33
  34 #include "wx/evtloop.h"
  35
  36
  37 #include "wx/except.h"
  38 #include "wx/ptr_scpd.h"
  39
  40 #include "wx/msw/private.h"
  41
  42 #if wxUSE_GUI
  43     #include "wx/tooltip.h"
  44     #if wxUSE_THREADS
  45         #include "wx/thread.h"
  46
  47         // define the list of MSG strutures
  48         WX_DECLARE_LIST(MSG, wxMsgList);
  49
  50         #include "wx/listimpl.cpp"
  51
  52         WX_DEFINE_LIST(wxMsgList)
  53     #endif // wxUSE_THREADS
  54 #endif //wxUSE_GUI
  55
  56 #if wxUSE_BASE
  57
  58 // ============================================================================
  59 // wxMSWEventLoopBase implementation
  60 // ============================================================================
  61
  62 // ----------------------------------------------------------------------------
  63 // ctor/dtor
  64 // ----------------------------------------------------------------------------
  65
  66 wxMSWEventLoopBase::wxMSWEventLoopBase()
  67 {
  68     m_shouldExit = false;
  69     m_exitcode = 0;
  70 }
  71
  72 // ----------------------------------------------------------------------------
  73 // wxEventLoop message processing dispatching
  74 // ----------------------------------------------------------------------------
  75
  76 bool wxMSWEventLoopBase::Pending() const
  77 {
  78     MSG msg;
  79     return ::PeekMessage(&msg, 0, 0, 0, PM_NOREMOVE) != 0;
  80 }
  81
  82 bool wxMSWEventLoopBase::GetNextMessage(WXMSG* msg)
  83 {
  84     wxCHECK_MSG( IsRunning(), false, _T("can't get messages if not running") );
  85
  86     const BOOL rc = ::GetMessage(msg, NULL, 0, 0);
  87
  88     if ( rc == 0 )
  89     {
  90         // got WM_QUIT
  91         return false;
  92     }
  93
  94     if ( rc == -1 )
  95     {
  96         // should never happen, but let's test for it nevertheless
  97         wxLogLastError(wxT("GetMessage"));
  98
  99         // still break from the loop
 100         return false;
 101     }
 102
 103     return true;
 104 }
 105
 106 #endif // wxUSE_BASE
 107
 108 #if wxUSE_GUI
 109
 110 // ============================================================================
 111 // GUI wxEventLoop implementation
 112 // ============================================================================
 113
 114 wxWindowMSW *wxGUIEventLoop::ms_winCritical = NULL;
 115
 116 bool wxGUIEventLoop::IsChildOfCriticalWindow(wxWindowMSW *win)
 117 {
 118     while ( win )
 119     {
 120         if ( win == ms_winCritical )
 121             return true;
 122
 123         win = win->GetParent();
 124     }
 125
 126     return false;
 127 }
 128
 129 bool wxGUIEventLoop::PreProcessMessage(WXMSG *msg)
 130 {
 131     HWND hwnd = msg->hwnd;
 132     wxWindow *wndThis = wxGetWindowFromHWND((WXHWND)hwnd);
 133     wxWindow *wnd;
 134
 135     // this might happen if we're in a modeless dialog, or if a wx control has
 136     // children which themselves were not created by wx (i.e. wxActiveX control children)
 137     if ( !wndThis )
 138     {
 139         while ( hwnd && (::GetWindowLong(hwnd, GWL_STYLE) & WS_CHILD ))
 140         {
 141             hwnd = ::GetParent(hwnd);
 142
 143             // If the control has a wx parent, break and give the parent a chance
 144             // to process the window message
 145             wndThis = wxGetWindowFromHWND((WXHWND)hwnd);
 146             if (wndThis != NULL)
 147                 break;
 148         }
 149
 150         if ( !wndThis )
 151         {
 152             // this may happen if the event occurred in a standard modeless dialog (the
 153             // only example of which I know of is the find/replace dialog) - then call
 154             // IsDialogMessage() to make TAB navigation in it work
 155
 156             // NOTE: IsDialogMessage() just eats all the messages (i.e. returns true for
 157             // them) if we call it for the control itself
 158             return hwnd && ::IsDialogMessage(hwnd, msg) != 0;
 159         }
 160     }
 161
 162     if ( !AllowProcessing(wndThis) )
 163     {
 164         // not a child of critical window, so we eat the event but take care to
 165         // stop an endless stream of WM_PAINTs which would have resulted if we
 166         // didn't validate the invalidated part of the window
 167         if ( msg->message == WM_PAINT )
 168             ::ValidateRect(hwnd, NULL);
 169
 170         return true;
 171     }
 172
 173 #if wxUSE_TOOLTIPS
 174     // we must relay WM_MOUSEMOVE events to the tooltip ctrl if we want it to
 175     // popup the tooltip bubbles
 176     if ( msg->message == WM_MOUSEMOVE )
 177     {
 178         // we should do it if one of window children has an associated tooltip
 179         // (and not just if the window has a tooltip itself)
 180         if ( wndThis->HasToolTips() )
 181             wxToolTip::RelayEvent((WXMSG *)msg);
 182     }
 183 #endif // wxUSE_TOOLTIPS
 184
 185     // allow the window to prevent certain messages from being
 186     // translated/processed (this is currently used by wxTextCtrl to always
 187     // grab Ctrl-C/V/X, even if they are also accelerators in some parent)
 188     if ( !wndThis->MSWShouldPreProcessMessage((WXMSG *)msg) )
 189     {
 190         return false;
 191     }
 192
 193     // try translations first: the accelerators override everything
 194     for ( wnd = wndThis; wnd; wnd = wnd->GetParent() )
 195     {
 196         if ( wnd->MSWTranslateMessage((WXMSG *)msg))
 197             return true;
 198
 199         // stop at first top level window, i.e. don't try to process the key
 200         // strokes originating in a dialog using the accelerators of the parent
 201         // frame - this doesn't make much sense
 202         if ( wnd->IsTopLevel() )
 203             break;
 204     }
 205
 206     // now try the other hooks (kbd navigation is handled here)
 207     for ( wnd = wndThis; wnd; wnd = wnd->GetParent() )
 208     {
 209         if ( wnd->MSWProcessMessage((WXMSG *)msg) )
 210             return true;
 211
 212         // also stop at first top level window here, just as above because
 213         // if we don't do this, pressing ESC on a modal dialog shown as child
 214         // of a modal dialog with wxID_CANCEL will cause the parent dialog to
 215         // be closed, for example
 216         if ( wnd->IsTopLevel() )
 217             break;
 218     }
 219
 220     // no special preprocessing for this message, dispatch it normally
 221     return false;
 222 }
 223
 224 void wxGUIEventLoop::ProcessMessage(WXMSG *msg)
 225 {
 226     // give us the chance to preprocess the message first
 227     if ( !PreProcessMessage(msg) )
 228     {
 229         // if it wasn't done, dispatch it to the corresponding window
 230         ::TranslateMessage(msg);
 231         ::DispatchMessage(msg);
 232     }
 233 }
 234
 235 bool wxGUIEventLoop::Dispatch()
 236 {
 237     MSG msg;
 238     if ( !GetNextMessage(&msg) )
 239         return false;
 240
 241 #if wxUSE_THREADS
 242     wxASSERT_MSG( wxThread::IsMain(),
 243                   wxT("only the main thread can process Windows messages") );
 244
 245     static bool s_hadGuiLock = true;
 246     static wxMsgList s_aSavedMessages;
 247
 248     // if a secondary thread owning the mutex is doing GUI calls, save all
 249     // messages for later processing - we can't process them right now because
 250     // it will lead to recursive library calls (and we're not reentrant)
 251     if ( !wxGuiOwnedByMainThread() )
 252     {
 253         s_hadGuiLock = false;
 254
 255         // leave out WM_COMMAND messages: too dangerous, sometimes
 256         // the message will be processed twice
 257         if ( !wxIsWaitingForThread() || msg.message != WM_COMMAND )
 258         {
 259             MSG* pMsg = new MSG(msg);
 260             s_aSavedMessages.Append(pMsg);
 261         }
 262
 263         return true;
 264     }
 265     else
 266     {
 267         // have we just regained the GUI lock? if so, post all of the saved
 268         // messages
 269         //
 270         // FIXME of course, it's not _exactly_ the same as processing the
 271         //       messages normally - expect some things to break...
 272         if ( !s_hadGuiLock )
 273         {
 274             s_hadGuiLock = true;
 275
 276             wxMsgList::compatibility_iterator node = s_aSavedMessages.GetFirst();
 277             while (node)
 278             {
 279                 MSG* pMsg = node->GetData();
 280                 s_aSavedMessages.Erase(node);
 281
 282                 ProcessMessage(pMsg);
 283                 delete pMsg;
 284
 285                 node = s_aSavedMessages.GetFirst();
 286             }
 287         }
 288     }
 289 #endif // wxUSE_THREADS
 290
 291     ProcessMessage(&msg);
 292
 293     return true;
 294 }
 295
 296 void wxGUIEventLoop::OnNextIteration()
 297 {
 298 #if wxUSE_THREADS
 299     wxMutexGuiLeaveOrEnter();
 300 #endif // wxUSE_THREADS
 301 }
 302
 303 void wxGUIEventLoop::WakeUp()
 304 {
 305     ::PostMessage(NULL, WM_NULL, 0, 0);
 306 }
 307
 308 #else // !wxUSE_GUI
 309
 310 void wxConsoleEventLoop::OnNextIteration()
 311 {
 312     if ( wxTheApp )
 313         wxTheApp->ProcessPendingEvents();
 314 }
 315
 316 void wxConsoleEventLoop::WakeUp()
 317 {
 318 #if wxUSE_THREADS
 319     wxWakeUpMainThread();
 320 #endif
 321 }
 322
 323 bool wxConsoleEventLoop::Dispatch()
 324 {
 325     MSG msg;
 326     if ( !GetNextMessage(&msg) )
 327         return false;
 328
 329     if ( msg.message == WM_TIMER )
 330     {
 331         TIMERPROC proc = (TIMERPROC)msg.lParam;
 332         if ( proc )
 333             (*proc)(NULL, 0, msg.wParam, 0);
 334     }
 335     else
 336     {
 337         wxLogDebug(_T("Ignoring unexpected message %d"), msg.message);
 338     }
 339
 340     return !m_shouldExit;
 341 }
 342
 343 #endif //wxUSE_GUI