X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/77fb1a02aac56528bbf3229af32634cc02795906..8e77fd8bca165aab9709649d79a7cbc6a172d4e1:/include/wx/evtloop.h?ds=sidebyside diff --git a/include/wx/evtloop.h b/include/wx/evtloop.h index 76319e3f1e..ee6759d5b3 100644 --- a/include/wx/evtloop.h +++ b/include/wx/evtloop.h @@ -12,26 +12,90 @@ #ifndef _WX_EVTLOOP_H_ #define _WX_EVTLOOP_H_ +#include "wx/event.h" #include "wx/utils.h" -class WXDLLEXPORT wxEventLoop; +// TODO: implement wxEventLoopSource for MSW (it should wrap a HANDLE and be +// monitored using MsgWaitForMultipleObjects()) +#if defined(__WXOSX__) || (defined(__UNIX__) && !defined(__WXMSW__)) + #define wxUSE_EVENTLOOP_SOURCE 1 +#else + #define wxUSE_EVENTLOOP_SOURCE 0 +#endif + +#if wxUSE_EVENTLOOP_SOURCE + class wxEventLoopSource; + class wxEventLoopSourceHandler; +#endif + +/* + NOTE ABOUT wxEventLoopBase::YieldFor LOGIC + ------------------------------------------ + + The YieldFor() function helps to avoid re-entrancy problems and problems + caused by out-of-order event processing + (see "wxYield-like problems" and "wxProgressDialog+threading BUG" wx-dev threads). + + The logic behind YieldFor() is simple: it analyzes the queue of the native + events generated by the underlying GUI toolkit and picks out and processes + only those matching the given mask. + + It's important to note that YieldFor() is used to selectively process the + events generated by the NATIVE toolkit. + Events syntethized by wxWidgets code or by user code are instead selectively + processed thanks to the logic built into wxEvtHandler::ProcessPendingEvents(). + In fact, when wxEvtHandler::ProcessPendingEvents gets called from inside a + YieldFor() call, wxEventLoopBase::IsEventAllowedInsideYield is used to decide + if the pending events for that event handler can be processed. + If all the pending events associated with that event handler result as "not processable", + the event handler "delays" itself calling wxEventLoopBase::DelayPendingEventHandler + (so it's moved: m_handlersWithPendingEvents => m_handlersWithPendingDelayedEvents). + Last, wxEventLoopBase::ProcessPendingEvents() before exiting moves the delayed + event handlers back into the list of handlers with pending events + (m_handlersWithPendingDelayedEvents => m_handlersWithPendingEvents) so that + a later call to ProcessPendingEvents() (possibly outside the YieldFor() call) + will process all pending events as usual. +*/ // ---------------------------------------------------------------------------- -// wxEventLoop: a GUI event loop +// wxEventLoopBase: interface for wxEventLoop // ---------------------------------------------------------------------------- -class WXDLLEXPORT wxEventLoopBase +class WXDLLIMPEXP_BASE wxEventLoopBase { public: // trivial, but needed (because of wxEventLoopBase) ctor - wxEventLoopBase() { } + wxEventLoopBase(); // dtor virtual ~wxEventLoopBase() { } + // use this to check whether the event loop was successfully created before + // using it + virtual bool IsOk() const { return true; } + + // returns true if this is the main loop + bool IsMain() const; + +#if wxUSE_EVENTLOOP_SOURCE + // create a new event loop source wrapping the given file descriptor and + // start monitoring it + virtual wxEventLoopSource * + AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags) = 0; +#endif // wxUSE_EVENTLOOP_SOURCE + + // dispatch&processing + // ------------------- + // start the event loop, return the exit code when it is finished virtual int Run() = 0; + // is this event loop running now? + // + // notice that even if this event loop hasn't terminated yet but has just + // spawned a nested (e.g. modal) event loop, this would return false + bool IsRunning() const; + // exit from the loop with the given exit code virtual void Exit(int rc = 0) = 0; @@ -41,66 +105,235 @@ public: // dispatch a single event, return false if we should exit from the loop virtual bool Dispatch() = 0; + // same as Dispatch() but doesn't wait for longer than the specified (in + // ms) timeout, return true if an event was processed, false if we should + // exit the loop or -1 if timeout expired + virtual int DispatchTimeout(unsigned long timeout) = 0; + + // implement this to wake up the loop: usually done by posting a dummy event + // to it (can be called from non main thread) + virtual void WakeUp() = 0; + + + // idle handling + // ------------- + + // make sure that idle events are sent again + virtual void WakeUpIdle(); + + // this virtual function is called when the application + // becomes idle and by default it forwards to wxApp::ProcessIdle() and + // while it can be overridden in a custom event loop, you must call the + // base class version to ensure that idle events are still generated + // + // it should return true if more idle events are needed, false if not + virtual bool ProcessIdle(); + + + // Yield-related hooks + // ------------------- + + // process all currently pending events right now + // + // it is an error to call Yield() recursively unless the value of + // onlyIfNeeded is true + // + // WARNING: this function is dangerous as it can lead to unexpected + // reentrancies (i.e. when called from an event handler it + // 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; + + // returns true if the main thread is inside a Yield() call + virtual bool IsYielding() const + { return m_isInsideYield; } + + // returns true if events of the given event category should be immediately + // processed inside a wxApp::Yield() call or rather should be queued for + // later processing by the main event loop + virtual bool IsEventAllowedInsideYield(wxEventCategory cat) const + { return (m_eventsToProcessInsideYield & cat) != 0; } + + // no SafeYield hooks since it uses wxWindow which is not available when wxUSE_GUI=0 + + + // active loop + // ----------- + // return currently active (running) event loop, may be NULL - static wxEventLoop *GetActive() { return ms_activeLoop; } + static wxEventLoopBase *GetActive() { return ms_activeLoop; } // set currently active (running) event loop - static void SetActive(wxEventLoop* loop) { ms_activeLoop = loop; } + static void SetActive(wxEventLoopBase* loop); - // is this event loop running now? - // - // notice that even if this event loop hasn't terminated yet but has just - // spawned a nested (e.g. modal) event loop, this would return false - bool IsRunning() const; protected: // 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) - virtual void OnExit() { } - + virtual void OnExit(); // the pointer to currently active loop - static wxEventLoop *ms_activeLoop; + static wxEventLoopBase *ms_activeLoop; + + // YieldFor() helpers: + bool m_isInsideYield; + long m_eventsToProcessInsideYield; - DECLARE_NO_COPY_CLASS(wxEventLoopBase) + wxDECLARE_NO_COPY_CLASS(wxEventLoopBase); }; +#if defined(__WINDOWS__) || defined(__WXMAC__) || defined(__WXDFB__) || (defined(__UNIX__) && !defined(__WXOSX__)) + +// this class can be used to implement a standard event loop logic using +// Pending() and Dispatch() +// +// it also handles idle processing automatically +class WXDLLIMPEXP_BASE wxEventLoopManual : public wxEventLoopBase +{ +public: + wxEventLoopManual(); + + // enters a loop calling OnNextIteration(), Pending() and Dispatch() and + // terminating when Exit() is called + virtual int Run(); + + // sets the "should exit" flag and wakes up the loop so that it terminates + // soon + virtual void Exit(int rc = 0); + +protected: + // may be overridden to perform some action at the start of each new event + // loop iteration + virtual void OnNextIteration() { } + + + // the loop exit code + int m_exitcode; + + // should we exit the loop? + bool m_shouldExit; + +private: + // process all already pending events and dispatch a new one (blocking + // until it appears in the event queue if necessary) + // + // returns the return value of Dispatch() + bool ProcessEvents(); + + wxDECLARE_NO_COPY_CLASS(wxEventLoopManual); +}; + +#endif // platforms using "manual" loop + // we're moving away from old m_impl wxEventLoop model as otherwise the user // code doesn't have access to platform-specific wxEventLoop methods and this // can sometimes be very useful (e.g. under MSW this is necessary for -// integration with MFC) but currently this is done for MSW only, other ports -// should follow a.s.a.p. -#if defined(__WXPALMOS__) - #include "wx/palmos/evtloop.h" -#elif defined(__WXMSW__) +// integration with MFC) but currently this is not done for all ports yet (e.g. +// wxX11) so fall back to the old wxGUIEventLoop definition below for them + +#if defined(__DARWIN__) + // CoreFoundation-based event loop is currently in wxBase so include it in + // any case too (although maybe it actually shouldn't be there at all) + #include "wx/osx/core/evtloop.h" +#endif + +// include the header defining wxConsoleEventLoop +#if defined(__UNIX__) && !defined(__WXMSW__) + #include "wx/unix/evtloop.h" +#elif defined(__WINDOWS__) + #include "wx/msw/evtloopconsole.h" +#endif + +#if wxUSE_GUI + +// include the appropriate header defining wxGUIEventLoop + +#if defined(__WXMSW__) #include "wx/msw/evtloop.h" -#else +#elif defined(__WXCOCOA__) + #include "wx/cocoa/evtloop.h" +#elif defined(__WXOSX__) + #include "wx/osx/evtloop.h" +#elif defined(__WXDFB__) + #include "wx/dfb/evtloop.h" +#elif defined(__WXGTK20__) + #include "wx/gtk/evtloop.h" +#else // other platform -class WXDLLEXPORT wxEventLoopImpl; +#include "wx/stopwatch.h" // for wxMilliClock_t -class WXDLLEXPORT wxEventLoop : public wxEventLoopBase +class WXDLLIMPEXP_FWD_CORE wxEventLoopImpl; + +class WXDLLIMPEXP_CORE wxGUIEventLoop : public wxEventLoopBase { public: - wxEventLoop() { m_impl = NULL; } - virtual ~wxEventLoop(); + wxGUIEventLoop() { m_impl = NULL; } + virtual ~wxGUIEventLoop(); + +#if wxUSE_EVENTLOOP_SOURCE + // We need to define a base class pure virtual method but we can't provide + // a generic implementation for it so simply fail. + virtual wxEventLoopSource * + AddSourceForFD(int WXUNUSED(fd), + wxEventLoopSourceHandler * WXUNUSED(handler), + int WXUNUSED(flags)) + { + wxFAIL_MSG( "support for event loop sources not implemented" ); + return NULL; + } +#endif // wxUSE_EVENTLOOP_SOURCE virtual int Run(); virtual void Exit(int rc = 0); virtual bool Pending() const; virtual bool Dispatch(); + virtual int DispatchTimeout(unsigned long timeout) + { + // TODO: this is, of course, horribly inefficient and a proper wait with + // timeout should be implemented for all ports natively... + const wxMilliClock_t timeEnd = wxGetLocalTimeMillis() + timeout; + for ( ;; ) + { + if ( Pending() ) + return Dispatch(); + + if ( wxGetLocalTimeMillis() >= timeEnd ) + return -1; + } + } + virtual void WakeUp() { } + virtual bool YieldFor(long eventsToProcess); protected: // the pointer to the port specific implementation class wxEventLoopImpl *m_impl; - DECLARE_NO_COPY_CLASS(wxEventLoop) - }; + wxDECLARE_NO_COPY_CLASS(wxGUIEventLoop); +}; + +#endif // platforms -#endif // __WXMSW__/!__WXMSW__ +#endif // wxUSE_GUI + +#if wxUSE_GUI + // we use a class rather than a typedef because wxEventLoop is + // forward-declared in many places + class wxEventLoop : public wxGUIEventLoop { }; +#else // !wxUSE_GUI + // we can't define wxEventLoop differently in GUI and base libraries so use + // a #define to still allow writing wxEventLoop in the user code + #if wxUSE_CONSOLE_EVENTLOOP && (defined(__WINDOWS__) || defined(__UNIX__)) + #define wxEventLoop wxConsoleEventLoop + #else // we still must define it somehow for the code below... + #define wxEventLoop wxEventLoopBase + #endif +#endif inline bool wxEventLoopBase::IsRunning() const { return GetActive() == this; } +#if wxUSE_GUI && !defined(__WXOSX__) // ---------------------------------------------------------------------------- // wxModalEventLoop // ---------------------------------------------------------------------------- @@ -109,7 +342,7 @@ inline bool wxEventLoopBase::IsRunning() const { return GetActive() == this; } // implement modality, we will surely need platform-specific implementations // too, this generic implementation is here only temporarily to see how it // works -class WXDLLEXPORT wxModalEventLoop : public wxEventLoop +class WXDLLIMPEXP_CORE wxModalEventLoop : public wxGUIEventLoop { public: wxModalEventLoop(wxWindow *winModal) @@ -123,13 +356,15 @@ protected: delete m_windowDisabler; m_windowDisabler = NULL; - wxEventLoop::OnExit(); + wxGUIEventLoop::OnExit(); } private: wxWindowDisabler *m_windowDisabler; }; +#endif //wxUSE_GUI + // ---------------------------------------------------------------------------- // wxEventLoopActivator: helper class for wxEventLoop implementations // ---------------------------------------------------------------------------- @@ -140,20 +375,50 @@ private: class wxEventLoopActivator { public: - wxEventLoopActivator(wxEventLoop *evtLoop) + wxEventLoopActivator(wxEventLoopBase *evtLoop) { - m_evtLoopOld = wxEventLoop::GetActive(); - wxEventLoop::SetActive(evtLoop); + m_evtLoopOld = wxEventLoopBase::GetActive(); + wxEventLoopBase::SetActive(evtLoop); } ~wxEventLoopActivator() { // restore the previously active event loop - wxEventLoop::SetActive(m_evtLoopOld); + wxEventLoopBase::SetActive(m_evtLoopOld); + } + +private: + wxEventLoopBase *m_evtLoopOld; +}; + +#if wxUSE_CONSOLE_EVENTLOOP + +class wxEventLoopGuarantor +{ +public: + wxEventLoopGuarantor() + { + m_evtLoopNew = NULL; + if (!wxEventLoop::GetActive()) + { + m_evtLoopNew = new wxEventLoop; + wxEventLoop::SetActive(m_evtLoopNew); + } + } + + ~wxEventLoopGuarantor() + { + if (m_evtLoopNew) + { + wxEventLoop::SetActive(NULL); + delete m_evtLoopNew; + } } private: - wxEventLoop *m_evtLoopOld; + wxEventLoop *m_evtLoopNew; }; +#endif // wxUSE_CONSOLE_EVENTLOOP + #endif // _WX_EVTLOOP_H_