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 array of MSG strutures
48 WX_DECLARE_OBJARRAY(MSG
, wxMsgArray
);
50 #include "wx/arrimpl.cpp"
52 WX_DEFINE_OBJARRAY(wxMsgArray
);
53 #endif // wxUSE_THREADS
55 // ----------------------------------------------------------------------------
57 // ----------------------------------------------------------------------------
59 class WXDLLEXPORT wxEventLoopImpl
63 wxEventLoopImpl() { m_exitcode
= 0; m_shouldExit
= false; }
66 void ProcessMessage(MSG
*msg
);
68 // generate an idle message, return TRUE if more idle time requested
69 bool SendIdleMessage();
71 // set/get the exit code
72 void Exit(int exitcode
) { m_exitcode
= exitcode
; m_shouldExit
= true; }
73 int GetExitCode() const { return m_exitcode
; }
74 bool ShouldExit() const { return m_shouldExit
; }
76 enum wxCatchAllResponse
{
81 wxCatchAllResponse
OnCatchAll();
84 // preprocess a message, return TRUE if processed (i.e. no further
85 // dispatching required)
86 bool PreProcessMessage(MSG
*msg
);
88 // the exit code of the event loop
91 // true if we were asked to terminate
95 // ----------------------------------------------------------------------------
97 // ----------------------------------------------------------------------------
99 wxDEFINE_TIED_SCOPED_PTR_TYPE(wxEventLoopImpl
);
101 // this object sets the wxEventLoop given to the ctor as the currently active
102 // one and unsets it in its dtor
103 class wxEventLoopActivator
106 wxEventLoopActivator(wxEventLoop
**pActive
,
107 wxEventLoop
*evtLoop
)
110 m_evtLoopOld
= *pActive
;
114 ~wxEventLoopActivator()
116 // restore the previously active event loop
117 *m_pActive
= m_evtLoopOld
;
121 wxEventLoop
*m_evtLoopOld
;
122 wxEventLoop
**m_pActive
;
125 // ============================================================================
126 // wxEventLoopImpl implementation
127 // ============================================================================
129 // ----------------------------------------------------------------------------
130 // wxEventLoopImpl message processing
131 // ----------------------------------------------------------------------------
133 void wxEventLoopImpl::ProcessMessage(MSG
*msg
)
135 // give us the chance to preprocess the message first
136 if ( !PreProcessMessage(msg
) )
138 // if it wasn't done, dispatch it to the corresponding window
139 ::TranslateMessage(msg
);
140 ::DispatchMessage(msg
);
144 bool wxEventLoopImpl::PreProcessMessage(MSG
*msg
)
146 HWND hwnd
= msg
->hwnd
;
147 wxWindow
*wndThis
= wxGetWindowFromHWND((WXHWND
)hwnd
);
149 // this may happen if the event occured in a standard modeless dialog (the
150 // only example of which I know of is the find/replace dialog) - then call
151 // IsDialogMessage() to make TAB navigation in it work
154 // we need to find the dialog containing this control as
155 // IsDialogMessage() just eats all the messages (i.e. returns TRUE for
156 // them) if we call it for the control itself
157 while ( hwnd
&& ::GetWindowLong(hwnd
, GWL_STYLE
) & WS_CHILD
)
159 hwnd
= ::GetParent(hwnd
);
162 return hwnd
&& ::IsDialogMessage(hwnd
, msg
) != 0;
166 // we must relay WM_MOUSEMOVE events to the tooltip ctrl if we want it to
167 // popup the tooltip bubbles
168 if ( msg
->message
== WM_MOUSEMOVE
)
170 wxToolTip
*tt
= wndThis
->GetToolTip();
173 tt
->RelayEvent((WXMSG
*)msg
);
176 #endif // wxUSE_TOOLTIPS
178 // allow the window to prevent certain messages from being
179 // translated/processed (this is currently used by wxTextCtrl to always
180 // grab Ctrl-C/V/X, even if they are also accelerators in some parent)
181 if ( !wndThis
->MSWShouldPreProcessMessage((WXMSG
*)msg
) )
186 // try translations first: the accelerators override everything
189 for ( wnd
= wndThis
; wnd
; wnd
= wnd
->GetParent() )
191 if ( wnd
->MSWTranslateMessage((WXMSG
*)msg
))
194 // stop at first top level window, i.e. don't try to process the key
195 // strokes originating in a dialog using the accelerators of the parent
196 // frame - this doesn't make much sense
197 if ( wnd
->IsTopLevel() )
201 // now try the other hooks (kbd navigation is handled here): we start from
202 // wndThis->GetParent() because wndThis->MSWProcessMessage() was already
204 for ( wnd
= wndThis
->GetParent(); wnd
; wnd
= wnd
->GetParent() )
206 if ( wnd
->MSWProcessMessage((WXMSG
*)msg
) )
210 // no special preprocessing for this message, dispatch it normally
214 // ----------------------------------------------------------------------------
215 // wxEventLoopImpl idle event processing
216 // ----------------------------------------------------------------------------
218 bool wxEventLoopImpl::SendIdleMessage()
220 return wxTheApp
->ProcessIdle();
223 // ----------------------------------------------------------------------------
224 // wxEventLoopImpl exception handling
225 // ----------------------------------------------------------------------------
227 wxEventLoopImpl::wxCatchAllResponse
wxEventLoopImpl::OnCatchAll()
229 switch (::MessageBox(NULL
,
230 _T("An unhandled exception occurred. 'Abort' will terminate the program,\r\n"
231 "'Retry' will close the current dialog, 'Ignore' will try to continue."),
232 _T("Unhandled exception"),
233 MB_ABORTRETRYIGNORE
|MB_ICONERROR
|MB_TASKMODAL
))
235 case IDABORT
: return catch_rethrow
;
236 case IDRETRY
: return catch_exit
;
237 case IDIGNORE
: return catch_continue
;
239 return catch_rethrow
;
242 // ============================================================================
243 // wxEventLoop implementation
244 // ============================================================================
246 wxEventLoop
*wxEventLoop::ms_activeLoop
= NULL
;
248 // ----------------------------------------------------------------------------
249 // wxEventLoop running and exiting
250 // ----------------------------------------------------------------------------
252 wxEventLoop::~wxEventLoop()
254 wxASSERT_MSG( !m_impl
, _T("should have been deleted in Run()") );
257 bool wxEventLoop::IsRunning() const
259 return m_impl
!= NULL
;
262 int wxEventLoop::Run()
264 // event loops are not recursive, you need to create another loop!
265 wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
267 // SendIdleMessage() and Dispatch() below may throw so the code here should
268 // be exception-safe, hence we must use local objects for all actions we
270 wxEventLoopActivator
activate(&ms_activeLoop
, this);
271 wxEventLoopImplTiedPtr
impl(&m_impl
, new wxEventLoopImpl
);
273 // we must ensure that OnExit() is called even if an exception is thrown
274 // from inside Dispatch() but we must call it from Exit() in normal
275 // situations because it is supposed to be called synchronously,
276 // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or
277 // something similar here)
279 bool retryAfterException
;
281 retryAfterException
=false;
288 wxMutexGuiLeaveOrEnter();
289 #endif // wxUSE_THREADS
291 // generate and process idle events for as long as we don't have
292 // anything else to do
293 while ( !Pending() && m_impl
->SendIdleMessage() )
296 // if the "should exit" flag is set, the loop should terminate but
297 // not before processing any remaining messages so while Pending()
298 // returns true, do process them
299 if ( m_impl
->ShouldExit() )
307 // a message came or no more idle processing to do, sit in
308 // Dispatch() waiting for the next message
317 switch (m_impl
->OnCatchAll()) {
318 case wxEventLoopImpl::catch_continue
:
319 retryAfterException
=true;
321 case wxEventLoopImpl::catch_exit
:
324 case wxEventLoopImpl::catch_rethrow
:
326 // should be replaced with wx macro, but
327 // there is none yet. OTOH, wxCATCH_ALL isn't
328 // expanded unless wxUSE_EXCEPTIONS, so its
329 // safe to use throw here.
335 } while (retryAfterException
);
338 return m_impl
->GetExitCode();
341 void wxEventLoop::Exit(int rc
)
343 wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
349 // all we have to do to exit from the loop is to (maybe) wake it up so that
350 // it can notice that Exit() had been called
352 // in particular, we do *not* use PostQuitMessage() here because we're not
353 // sure that WM_QUIT is going to be processed by the correct event loop: it
354 // is possible that another one is started before this one has a chance to
356 ::PostMessage(NULL
, WM_NULL
, 0, 0);
359 // ----------------------------------------------------------------------------
360 // wxEventLoop message processing dispatching
361 // ----------------------------------------------------------------------------
363 bool wxEventLoop::Pending() const
366 return ::PeekMessage(&msg
, 0, 0, 0, PM_NOREMOVE
) != 0;
369 bool wxEventLoop::Dispatch()
371 wxCHECK_MSG( IsRunning(), FALSE
, _T("can't call Dispatch() if not running") );
374 BOOL rc
= ::GetMessage(&msg
, (HWND
) NULL
, 0, 0);
384 // should never happen, but let's test for it nevertheless
385 wxLogLastError(wxT("GetMessage"));
387 // still break from the loop
392 wxASSERT_MSG( wxThread::IsMain(),
393 wxT("only the main thread can process Windows messages") );
395 static bool s_hadGuiLock
= TRUE
;
396 static wxMsgArray s_aSavedMessages
;
398 // if a secondary thread owning the mutex is doing GUI calls, save all
399 // messages for later processing - we can't process them right now because
400 // it will lead to recursive library calls (and we're not reentrant)
401 if ( !wxGuiOwnedByMainThread() )
403 s_hadGuiLock
= FALSE
;
405 // leave out WM_COMMAND messages: too dangerous, sometimes
406 // the message will be processed twice
407 if ( !wxIsWaitingForThread() || msg
.message
!= WM_COMMAND
)
409 s_aSavedMessages
.Add(msg
);
416 // have we just regained the GUI lock? if so, post all of the saved
419 // FIXME of course, it's not _exactly_ the same as processing the
420 // messages normally - expect some things to break...
425 size_t count
= s_aSavedMessages
.Count();
426 for ( size_t n
= 0; n
< count
; n
++ )
428 MSG
& msg
= s_aSavedMessages
[n
];
429 m_impl
->ProcessMessage(&msg
);
432 s_aSavedMessages
.Empty();
435 #endif // wxUSE_THREADS
437 m_impl
->ProcessMessage(&msg
);