Refactor YieldFor() to avoid code duplication among the ports.

Don't repeat the same code in all the ports, move it to the common base class
and add a new virtual DoYieldFor() for the really port-specific code.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76061 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/cocoa/evtloop.h

@@ -24,10 +24,10 @@ public:
     virtual bool Dispatch();
     virtual int DispatchTimeout(unsigned long timeout);
     virtual void WakeUp() { }
-    virtual bool YieldFor(long eventsToProcess);
 
 protected:
     virtual int DoRun();
+    virtual void DoYieldFor(long eventsToProcess);
 
     int m_exitcode;
 

include/wx/evtloop.h

@@ -153,7 +153,12 @@ public:
     //          may result in calling the same event handler again), use
     //          with _extreme_ care or, better, don't use at all!
     bool Yield(bool onlyIfNeeded = false);
-    virtual bool YieldFor(long eventsToProcess) = 0;
+
+    // more selective version of Yield()
+    //
+    // notice that it is virtual for backwards-compatibility but new code
+    // should override DoYieldFor() and not YieldFor() itself
+    virtual bool YieldFor(long eventsToProcess);
 
     // returns true if the main thread is inside a Yield() call
     virtual bool IsYielding() const
@@ -182,6 +187,16 @@ protected:
     // real implementation of Run()
     virtual int DoRun() = 0;
 
+    // And the real, port-specific, implementation of YieldFor().
+    //
+    // The base class version is pure virtual to ensure that it is overridden
+    // in the derived classes but does have an implementation which processes
+    // pending events in wxApp if eventsToProcess allows it, and so should be
+    // called from the overridden version at an appropriate place (i.e. after
+    // processing the native events but before doing anything else that could
+    // be affected by pending events dispatching).
+    virtual void DoYieldFor(long eventsToProcess) = 0;
+
     // this function should be called before the event loop terminates, whether
     // this happens normally (because of Exit() call) or abnormally (because of
     // an exception thrown from inside the loop)
@@ -313,10 +328,10 @@ public:
         }
     }
     virtual void WakeUp() { }
-    virtual bool YieldFor(long eventsToProcess);
 
 protected:
     virtual int DoRun();
+    virtual void DoYieldFor(long eventsToProcess);
 
     // the pointer to the port specific implementation class
     wxEventLoopImpl *m_impl;

include/wx/gtk/evtloop.h

@@ -26,13 +26,13 @@ public:
     virtual bool Dispatch();
     virtual int DispatchTimeout(unsigned long timeout);
     virtual void WakeUp();
-    virtual bool YieldFor(long eventsToProcess);
 
     void StoreGdkEventForLaterProcessing(GdkEvent* ev)
         { m_arrGdkEvents.Add(ev); }
 
 protected:
     virtual int DoRun();
+    virtual void DoYieldFor(long eventsToProcess);
 
 private:
     // the exit code of this event loop

include/wx/msw/evtloop.h

@@ -54,10 +54,10 @@ public:
     virtual bool Dispatch();
     virtual int DispatchTimeout(unsigned long timeout);
     virtual void WakeUp();
-    virtual bool YieldFor(long eventsToProcess);
 
 protected:
     virtual void OnNextIteration();
+    virtual void DoYieldFor(long eventsToProcess);
 
 private:
     // check if the given window is a child of ms_winCritical (which must be

include/wx/msw/evtloopconsole.h

@@ -40,10 +40,12 @@ public:
     virtual bool Dispatch();
     virtual int DispatchTimeout(unsigned long timeout);
     virtual void WakeUp();
-    virtual bool YieldFor(long WXUNUSED(eventsToProcess)) { return true; }
 
     // Windows-specific function to process a single message
     virtual void ProcessMessage(WXMSG *msg);
+
+protected:
+    virtual void DoYieldFor(long eventsToProcess);
 };
 
 #endif // wxUSE_CONSOLE_EVENTLOOP

include/wx/osx/core/evtloop.h

@@ -42,8 +42,6 @@ public:
     // to it (can be called from non main thread)
     virtual void WakeUp();
 
-    virtual bool YieldFor(long eventsToProcess);
-
     bool ShouldProcessIdleEvents() const { return m_processIdleEvents ; }
     
 #if wxUSE_UIACTIONSIMULATOR
@@ -57,6 +55,8 @@ protected:
     // terminating when Exit() is called
     virtual int DoRun();
 
+    virtual void DoYieldFor(long eventsToProcess);
+
     void CommonModeObserverCallBack(CFRunLoopObserverRef observer, int activity);
     void DefaultModeObserverCallBack(CFRunLoopObserverRef observer, int activity);
 

include/wx/unix/evtloop.h

@@ -38,10 +38,10 @@ public:
     virtual int DispatchTimeout(unsigned long timeout);
     virtual void WakeUp();
     virtual bool IsOk() const { return m_dispatcher != NULL; }
-    virtual bool YieldFor(long WXUNUSED(eventsToProcess)) { return true; }
 
 protected:
     virtual void OnNextIteration();
+    virtual void DoYieldFor(long eventsToProcess);
 
 private:
     // pipe used for wake up messages: when a child thread wants to wake up

src/cocoa/evtloop.mm

@@ -111,17 +111,8 @@ int wxGUIEventLoop::DispatchTimeout(unsigned long timeout)
     return true;
 }
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-#if wxUSE_LOG
-    // disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    wxLog::Suspend();
-#endif // wxUSE_LOG
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
     // Run the event loop until it is out of events
     while (1)
     {
@@ -157,15 +148,5 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
         the main thread waits and then notify the main thread by posting
         an event.
      */
-    if (wxTheApp)
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-        wxTheApp->ProcessPendingEvents();
-
-#if wxUSE_LOG
-    // let the logs be flashed again
-    wxLog::Resume();
-#endif // wxUSE_LOG
-
-    m_isInsideYield = false;
-
-    return true;
 }

src/common/evtloopcmn.cpp

@@ -116,6 +116,49 @@ bool wxEventLoopBase::Yield(bool onlyIfNeeded)
     return YieldFor(wxEVT_CATEGORY_ALL);
 }
 
+bool wxEventLoopBase::YieldFor(long eventsToProcess)
+{
+#if wxUSE_THREADS
+    if ( !wxThread::IsMain() )
+    {
+        // Don't ever dispatch events from non-main threads.
+        return false;
+    }
+#endif // wxUSE_THREADS
+
+    // set the flag and don't forget to reset it before returning
+    m_isInsideYield = true;
+    m_eventsToProcessInsideYield = eventsToProcess;
+
+    wxON_BLOCK_EXIT_SET(m_isInsideYield, false);
+
+#if wxUSE_LOG
+    // disable log flushing from here because a call to wxYield() shouldn't
+    // normally result in message boxes popping up &c
+    wxLog::Suspend();
+
+    // ensure the logs will be flashed again when we exit
+    wxON_BLOCK_EXIT0(wxLog::Resume);
+#endif
+
+    DoYieldFor(eventsToProcess);
+
+    return true;
+}
+
+void wxEventLoopBase::DoYieldFor(long eventsToProcess)
+{
+    // Normally yielding dispatches not only the pending native events, but
+    // also the events pending in wxWidgets itself.
+    //
+    // Notice however that we must not do it if we're asked to process only the
+    // events of specific kind, as pending events could be of any kind at all
+    // (ideal would be to have a filtering version of ProcessPendingEvents()
+    // too but we don't have this right now).
+    if ( eventsToProcess == wxEVT_CATEGORY_ALL && wxTheApp )
+        wxTheApp->ProcessPendingEvents();
+}
+
 #if wxUSE_EVENTLOOP_SOURCE
 
 wxEventLoopSource*

src/dfb/evtloop.cpp

@@ -202,20 +202,8 @@ wxIDirectFBEventBufferPtr wxGUIEventLoop::GetDirectFBEventBuffer()
 // events dispatch and loop handling
 //-----------------------------------------------------------------------------
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-#if wxUSE_THREADS
-    if ( !wxThread::IsMain() )
-        return true; // can't process events from other threads
-#endif // wxUSE_THREADS
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
-#if wxUSE_LOG
-    wxLog::Suspend();
-#endif // wxUSE_LOG
-
     // TODO: implement event filtering using the eventsToProcess mask
 
     // process all pending events:
@@ -230,11 +218,5 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
     // OnUpdateUI() which is a nice (and desired) side effect)
     while ( ProcessIdle() ) {}
 
-#if wxUSE_LOG
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    wxLog::Resume();
-#endif // wxUSE_LOG
-
-    m_isInsideYield = false;
-
-    return true;
 }

src/gtk/evtloop.cpp

@@ -361,25 +361,8 @@ static void wxgtk_main_do_event(GdkEvent* event, void* data)
 }
 }
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-#if wxUSE_THREADS
-    if ( !wxThread::IsMain() )
-    {
-        // can't call gtk_main_iteration() from other threads like this
-        return true;
-    }
-#endif // wxUSE_THREADS
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
-#if wxUSE_LOG
-    // disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    wxLog::Suspend();
-#endif
-
     // temporarily replace the global GDK event handler with our function, which
     // categorizes the events and using m_eventsToProcessInsideYield decides
     // if an event should be processed immediately or not
@@ -393,15 +376,7 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
         gtk_main_iteration();
     gdk_event_handler_set ((GdkEventFunc)gtk_main_do_event, NULL, NULL);
 
-    // Process all pending events too, this is consistent with wxMSW behaviour
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    // and the behaviour of wxGTK itself in the previous versions.
-    //
-    // Notice however that we must not do it if we're asked to process only the
-    // events of specific kind, as pending events could be of any kind at all
-    // (ideal would be to have a filtering version of ProcessPendingEvents()
-    // too but we don't have this right now).
-    if ( eventsToProcess == wxEVT_CATEGORY_ALL && wxTheApp )
-        wxTheApp->ProcessPendingEvents();
 
     if (eventsToProcess != wxEVT_CATEGORY_CLIPBOARD)
     {
@@ -429,13 +404,4 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
     }
 
     m_arrGdkEvents.Clear();
-
-#if wxUSE_LOG
-    // let the logs be flashed again
-    wxLog::Resume();
-#endif
-
-    m_isInsideYield = false;
-
-    return true;
 }

src/gtk1/evtloop.cpp

@@ -150,29 +150,12 @@ bool wxGUIEventLoop::Dispatch()
 // wxYield
 //-----------------------------------------------------------------------------
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-#if wxUSE_THREADS
-    if ( !wxThread::IsMain() )
-    {
-        // can't call gtk_main_iteration() from other threads like this
-        return true;
-    }
-#endif // wxUSE_THREADS
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
     // We need to remove idle callbacks or the loop will
     // never finish.
     wxTheApp->RemoveIdleTag();
 
-#if wxUSE_LOG
-    // disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    wxLog::Suspend();
-#endif
-
     // TODO: implement event filtering using the eventsToProcess mask
     while (gtk_events_pending())
         gtk_main_iteration();
@@ -185,14 +168,7 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
     // return value of Processidle().
     ProcessIdle();
 
-#if wxUSE_LOG
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    // let the logs be flashed again
-    wxLog::Resume();
-#endif
-
-    m_isInsideYield = false;
-
-    return true;
 }
 
 class wxGUIEventLoopSourcesManager : public wxEventLoopSourcesManagerBase

src/motif/evtloop.cpp

@@ -130,18 +130,13 @@ void wxGUIEventLoop::ScheduleExit(int rc)
     ::wxBreakDispatch();
 }
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
     while (wxTheApp && wxTheApp->Pending())
         // TODO: implement event filtering using the eventsToProcess mask
         wxTheApp->Dispatch();
 
-    m_isInsideYield = false;
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-
-    return true;
 }
 
 // ----------------------------------------------------------------------------

src/msw/evtloop.cpp

@@ -34,7 +34,6 @@
 #include "wx/thread.h"
 #include "wx/except.h"
 #include "wx/msw/private.h"
-#include "wx/scopeguard.h"
 
 #include "wx/tooltip.h"
 #if wxUSE_THREADS
@@ -264,23 +263,8 @@ void wxGUIEventLoop::WakeUp()
 #include <wx/arrimpl.cpp>
 WX_DEFINE_OBJARRAY(wxMSGArray);
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
-    // set the flag and don't forget to reset it before returning
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
-    wxON_BLOCK_EXIT_SET(m_isInsideYield, false);
-
-#if wxUSE_LOG
-    // disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    wxLog::Suspend();
-
-    // ensure the logs will be flashed again when we exit
-    wxON_BLOCK_EXIT0(wxLog::Resume);
-#endif // wxUSE_LOG
-
     // we don't want to process WM_QUIT from here - it should be processed in
     // the main event loop in order to stop it
     MSG msg;
@@ -434,9 +418,7 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
         }
     }
 
-    // if there are pending events, we must process them.
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    if ( eventsToProcess == wxEVT_CATEGORY_ALL && wxTheApp )
-        wxTheApp->ProcessPendingEvents();
 
     // put back unprocessed events in the queue
     DWORD id = GetCurrentThreadId();
@@ -447,6 +429,4 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
     }
 
     m_arrMSG.Clear();
-
-    return true;
 }

src/msw/evtloopconsole.cpp

@@ -162,4 +162,9 @@ int wxConsoleEventLoop::DispatchTimeout(unsigned long timeout)
     return !m_shouldExit;
 }
 
+void wxConsoleEventLoop::DoYieldFor(long eventsToProcess)
+{
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
+}
+
 #endif // wxUSE_CONSOLE_EVENTLOOP

src/os2/evtloop.cpp

@@ -368,20 +368,11 @@ bool wxGUIEventLoop::Dispatch()
 //
 // Yield to incoming messages
 //
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
     HAB vHab = 0;
     QMSG vMsg;
 
-    //
-    // Disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    //
-    wxLog::Suspend();
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
     //
     // We want to go back to the main message loop
     // if we see a WM_QUIT. (?)
@@ -397,20 +388,10 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
             break;
     }
 
-    //
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    // If they are pending events, we must process them.
+
-    //
     if (eventsToProcess == wxEVT_CATEGORY_ALL && wxTheApp)
     {
-        wxTheApp->ProcessPendingEvents();
         wxTheApp->HandleSockets();
     }
-
-    //
-    // Let the logs be flashed again
-    //
-    wxLog::Resume();
-    m_isInsideYield = false;
-
-    return true;
 } // end of wxYield

src/osx/core/evtloop_cf.cpp

@@ -184,26 +184,8 @@ void wxMacWakeUp()
 
 #endif
 
-bool wxCFEventLoop::YieldFor(long eventsToProcess)
+void wxCFEventLoop::DoYieldFor(long eventsToProcess)
 {
-#if wxUSE_THREADS
-    // Yielding from a non-gui thread needs to bail out, otherwise we end up
-    // possibly sending events in the thread too.
-    if ( !wxThread::IsMain() )
-    {
-        return true;
-    }
-#endif // wxUSE_THREADS
-
-    m_isInsideYield = true;
-    m_eventsToProcessInsideYield = eventsToProcess;
-
-#if wxUSE_LOG
-    // disable log flushing from here because a call to wxYield() shouldn't
-    // normally result in message boxes popping up &c
-    wxLog::Suspend();
-#endif // wxUSE_LOG
-
     // process all pending events:
     while ( DoProcessEvents() == 1 )
         ;
@@ -213,16 +195,7 @@ bool wxCFEventLoop::YieldFor(long eventsToProcess)
     // OnUpdateUI() which is a nice (and desired) side effect)
     while ( ProcessIdle() ) {}
 
-    // if there are pending events, we must process them.
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
-    if ( eventsToProcess == wxEVT_CATEGORY_ALL && wxTheApp )
-        wxTheApp->ProcessPendingEvents();
-
-#if wxUSE_LOG
-    wxLog::Resume();
-#endif // wxUSE_LOG
-    m_isInsideYield = false;
-
-    return true;
 }
 
 // implement/override base class pure virtual

src/unix/evtloopunix.cpp

@@ -210,6 +210,10 @@ void wxConsoleEventLoop::OnNextIteration()
     wxTheApp->CheckSignal();
 }
 
+void wxConsoleEventLoop::DoYieldFor(long eventsToProcess)
+{
+    wxEventLoopBase::DoYieldFor(eventsToProcess);
+}
 
 wxEventLoopBase *wxConsoleAppTraits::CreateEventLoop()
 {

src/x11/evtloop.cpp

@@ -242,7 +242,7 @@ bool wxGUIEventLoop::Dispatch()
     return true;
 }
 
-bool wxGUIEventLoop::YieldFor(long eventsToProcess)
+void wxGUIEventLoop::DoYieldFor(long eventsToProcess)
 {
     // Sometimes only 2 yields seem
     // to do the trick, e.g. in the
@@ -250,9 +250,6 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
     int i;
     for (i = 0; i < 2; i++)
     {
-        m_isInsideYield = true;
-        m_eventsToProcessInsideYield = eventsToProcess;
-
         // Call dispatch at least once so that sockets
         // can be tested
         wxTheApp->Dispatch();
@@ -266,8 +263,6 @@ bool wxGUIEventLoop::YieldFor(long eventsToProcess)
 #endif
         ProcessIdle();
 
-        m_isInsideYield = false;
+        wxEventLoopBase::DoYieldFor(eventsToProcess);
     }
-
-    return true;
 }