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