1 ///////////////////////////////////////////////////////////////////////////////
2 // Name: msw/evtloop.cpp
3 // Purpose: implements wxEventLoop for MSW
4 // Author: Vadim Zeitlin
8 // Copyright: (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
9 // License: wxWindows licence
10 ///////////////////////////////////////////////////////////////////////////////
12 // ============================================================================
14 // ============================================================================
16 // ----------------------------------------------------------------------------
18 // ----------------------------------------------------------------------------
20 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
21 #pragma implementation "evtloop.h"
24 // For compilers that support precompilation, includes "wx.h".
25 #include "wx/wxprec.h"
32 #include "wx/window.h"
36 #include "wx/evtloop.h"
38 #include "wx/tooltip.h"
39 #include "wx/except.h"
40 #include "wx/ptr_scpd.h"
42 #include "wx/msw/private.h"
45 #include "wx/thread.h"
47 // define the list of MSG strutures
48 WX_DECLARE_LIST(MSG
, wxMsgList
);
50 #include "wx/listimpl.cpp"
52 WX_DEFINE_LIST(wxMsgList
);
53 #endif // wxUSE_THREADS
55 // ----------------------------------------------------------------------------
57 // ----------------------------------------------------------------------------
59 // this object sets the wxEventLoop given to the ctor as the currently active
60 // one and unsets it in its dtor
61 class wxEventLoopActivator
64 wxEventLoopActivator(wxEventLoop
**pActive
,
68 m_evtLoopOld
= *pActive
;
72 ~wxEventLoopActivator()
74 // restore the previously active event loop
75 *m_pActive
= m_evtLoopOld
;
79 wxEventLoop
*m_evtLoopOld
;
80 wxEventLoop
**m_pActive
;
83 // ============================================================================
84 // wxEventLoop implementation
85 // ============================================================================
87 wxEventLoop
*wxEventLoopBase::ms_activeLoop
= NULL
;
88 wxWindowMSW
*wxEventLoop::ms_winCritical
= NULL
;
90 // ----------------------------------------------------------------------------
92 // ----------------------------------------------------------------------------
94 wxEventLoop::wxEventLoop()
100 // ----------------------------------------------------------------------------
101 // wxEventLoop message processing
102 // ----------------------------------------------------------------------------
104 void wxEventLoop::ProcessMessage(WXMSG
*msg
)
106 // give us the chance to preprocess the message first
107 if ( !PreProcessMessage(msg
) )
109 // if it wasn't done, dispatch it to the corresponding window
110 ::TranslateMessage(msg
);
111 ::DispatchMessage(msg
);
115 bool wxEventLoop::IsChildOfCriticalWindow(wxWindowMSW
*win
)
119 if ( win
== ms_winCritical
)
122 win
= win
->GetParent();
128 bool wxEventLoop::PreProcessMessage(WXMSG
*msg
)
130 HWND hwnd
= msg
->hwnd
;
131 wxWindow
* const wndThis
= wxGetWindowFromHWND((WXHWND
)hwnd
);
134 // this may happen if the event occurred in a standard modeless dialog (the
135 // only example of which I know of is the find/replace dialog) - then call
136 // IsDialogMessage() to make TAB navigation in it work
139 // we need to find the dialog containing this control as
140 // IsDialogMessage() just eats all the messages (i.e. returns true for
141 // them) if we call it for the control itself
142 while ( hwnd
&& ::GetWindowLong(hwnd
, GWL_STYLE
) & WS_CHILD
)
144 hwnd
= ::GetParent(hwnd
);
147 return hwnd
&& ::IsDialogMessage(hwnd
, msg
) != 0;
150 if ( !AllowProcessing(wndThis
) )
152 // not a child of critical window, so we eat the event but take care to
153 // stop an endless stream of WM_PAINTs which would have resulted if we
154 // didn't validate the invalidated part of the window
155 if ( msg
->message
== WM_PAINT
)
156 ::ValidateRect(hwnd
, NULL
);
162 // we must relay WM_MOUSEMOVE events to the tooltip ctrl if we want it to
163 // popup the tooltip bubbles
164 if ( msg
->message
== WM_MOUSEMOVE
)
166 wxToolTip
*tt
= wndThis
->GetToolTip();
169 tt
->RelayEvent((WXMSG
*)msg
);
172 #endif // wxUSE_TOOLTIPS
174 // allow the window to prevent certain messages from being
175 // translated/processed (this is currently used by wxTextCtrl to always
176 // grab Ctrl-C/V/X, even if they are also accelerators in some parent)
177 if ( !wndThis
->MSWShouldPreProcessMessage((WXMSG
*)msg
) )
182 // try translations first: the accelerators override everything
183 for ( wnd
= wndThis
; wnd
; wnd
= wnd
->GetParent() )
185 if ( wnd
->MSWTranslateMessage((WXMSG
*)msg
))
188 // stop at first top level window, i.e. don't try to process the key
189 // strokes originating in a dialog using the accelerators of the parent
190 // frame - this doesn't make much sense
191 if ( wnd
->IsTopLevel() )
195 // now try the other hooks (kbd navigation is handled here)
196 for ( wnd
= wndThis
; wnd
; wnd
= wnd
->GetParent() )
198 if (wnd
!= wndThis
) // Skip the first since wndThis->MSWProcessMessage() was called above
200 if ( wnd
->MSWProcessMessage((WXMSG
*)msg
) )
204 // Stop at first top level window (as per comment above).
205 // If we don't do this, pressing ESC on a modal dialog shown as child of a modal
206 // dialog with wxID_CANCEL will cause the parent dialog to be closed, for example
207 if (wnd
->IsTopLevel())
211 // no special preprocessing for this message, dispatch it normally
215 // ----------------------------------------------------------------------------
216 // wxEventLoop running and exiting
217 // ----------------------------------------------------------------------------
219 bool wxEventLoop::IsRunning() const
221 return ms_activeLoop
== this;
224 int wxEventLoop::Run()
226 // event loops are not recursive, you need to create another loop!
227 wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
229 // ProcessIdle() and Dispatch() below may throw so the code here should
230 // be exception-safe, hence we must use local objects for all actions we
232 wxEventLoopActivator
activate(&ms_activeLoop
, this);
234 // we must ensure that OnExit() is called even if an exception is thrown
235 // from inside Dispatch() but we must call it from Exit() in normal
236 // situations because it is supposed to be called synchronously,
237 // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
238 // something similar here)
244 #endif // wxUSE_EXCEPTIONS
246 // this is the event loop itself
250 wxMutexGuiLeaveOrEnter();
251 #endif // wxUSE_THREADS
253 // generate and process idle events for as long as we don't
254 // have anything else to do
255 while ( !Pending() && (wxTheApp
&& wxTheApp
->ProcessIdle()) )
258 // if the "should exit" flag is set, the loop should terminate
259 // but not before processing any remaining messages so while
260 // Pending() returns true, do process them
269 // a message came or no more idle processing to do, sit in
270 // Dispatch() waiting for the next message
279 // exit the outer loop as well
286 if ( !wxTheApp
|| !wxTheApp
->OnExceptionInMainLoop() )
291 //else: continue running the event loop
295 // OnException() throwed, possibly rethrowing the same
296 // exception again: very good, but we still need OnExit() to
303 #endif // wxUSE_EXCEPTIONS
308 void wxEventLoop::Exit(int rc
)
310 wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
317 // all we have to do to exit from the loop is to (maybe) wake it up so that
318 // it can notice that Exit() had been called
320 // in particular, we do *not* use PostQuitMessage() here because we're not
321 // sure that WM_QUIT is going to be processed by the correct event loop: it
322 // is possible that another one is started before this one has a chance to
324 ::PostMessage(NULL
, WM_NULL
, 0, 0);
327 // ----------------------------------------------------------------------------
328 // wxEventLoop message processing dispatching
329 // ----------------------------------------------------------------------------
331 bool wxEventLoop::Pending() const
334 return ::PeekMessage(&msg
, 0, 0, 0, PM_NOREMOVE
) != 0;
337 bool wxEventLoop::Dispatch()
339 wxCHECK_MSG( IsRunning(), false, _T("can't call Dispatch() if not running") );
342 BOOL rc
= ::GetMessage(&msg
, (HWND
) NULL
, 0, 0);
352 // should never happen, but let's test for it nevertheless
353 wxLogLastError(wxT("GetMessage"));
355 // still break from the loop
360 wxASSERT_MSG( wxThread::IsMain(),
361 wxT("only the main thread can process Windows messages") );
363 static bool s_hadGuiLock
= true;
364 static wxMsgList s_aSavedMessages
;
366 // if a secondary thread owning the mutex is doing GUI calls, save all
367 // messages for later processing - we can't process them right now because
368 // it will lead to recursive library calls (and we're not reentrant)
369 if ( !wxGuiOwnedByMainThread() )
371 s_hadGuiLock
= false;
373 // leave out WM_COMMAND messages: too dangerous, sometimes
374 // the message will be processed twice
375 if ( !wxIsWaitingForThread() || msg
.message
!= WM_COMMAND
)
377 MSG
* pMsg
= new MSG(msg
);
378 s_aSavedMessages
.Append(pMsg
);
385 // have we just regained the GUI lock? if so, post all of the saved
388 // FIXME of course, it's not _exactly_ the same as processing the
389 // messages normally - expect some things to break...
394 wxMsgList::compatibility_iterator node
= s_aSavedMessages
.GetFirst();
397 MSG
* pMsg
= node
->GetData();
398 s_aSavedMessages
.Erase(node
);
400 ProcessMessage(pMsg
);
403 node
= s_aSavedMessages
.GetFirst();
407 #endif // wxUSE_THREADS
409 ProcessMessage(&msg
);