// Author: Vadim Zeitlin
// Modified by:
// Created: 01.06.01
-// RCS-ID: $Id$
// Copyright: (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
#ifndef _WX_EVTLOOP_H_
#define _WX_EVTLOOP_H_
+#include "wx/event.h"
#include "wx/utils.h"
+// 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.
+*/
+
// ----------------------------------------------------------------------------
// wxEventLoopBase: interface for wxEventLoop
// ----------------------------------------------------------------------------
{
public:
// trivial, but needed (because of wxEventLoopBase) ctor
- wxEventLoopBase() { }
+ wxEventLoopBase();
// dtor
virtual ~wxEventLoopBase() { }
// 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
+ // monitor it for events occurring on this descriptor in all event loops
+ static wxEventLoopSource *
+ AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags);
+#endif // wxUSE_EVENTLOOP_SOURCE
+
+ // dispatch&processing
+ // -------------------
+
// start the event loop, return the exit code when it is finished
- virtual int Run() = 0;
+ //
+ // notice that wx ports should override DoRun(), this method is virtual
+ // only to allow overriding it in the user code for custom event loops
+ virtual int Run();
+
+ // 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;
+ //
+ // this can be only used to exit the currently running loop, use
+ // ScheduleExit() if this might not be the case
+ virtual void Exit(int rc = 0);
+
+ // ask the event loop to exit with the given exit code, can be used even if
+ // this loop is not running right now but the loop must have been started,
+ // i.e. Run() should have been already called
+ virtual void ScheduleExit(int rc = 0) = 0;
// return true if any events are available
virtual bool Pending() const = 0;
// 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 wxEventLoopBase *GetActive() { return ms_activeLoop; }
// set currently active (running) event loop
- static void SetActive(wxEventLoopBase* 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;
-
- // 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;
protected:
+ // real implementation of Run()
+ virtual int DoRun() = 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)
- virtual void OnExit() { }
+ virtual void OnExit();
+
+ // Return true if we're currently inside our Run(), even if another nested
+ // event loop is currently running, unlike IsRunning() (which should have
+ // been really called IsActive() but it's too late to change this now).
+ bool IsInsideRun() const { return m_isInsideRun; }
// the pointer to currently active loop
static wxEventLoopBase *ms_activeLoop;
- DECLARE_NO_COPY_CLASS(wxEventLoopBase)
+ // should we exit the loop?
+ bool m_shouldExit;
+
+ // YieldFor() helpers:
+ bool m_isInsideYield;
+ long m_eventsToProcessInsideYield;
+
+private:
+ // this flag is set on entry into Run() and reset before leaving it
+ bool m_isInsideRun;
+
+ wxDECLARE_NO_COPY_CLASS(wxEventLoopBase);
};
-#if defined(__WXMSW__) || defined(__WXMAC__) || defined(__WXDFB__) || defined(__UNIX__)
+#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()
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);
+ virtual void ScheduleExit(int rc = 0);
protected:
+ // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
+ // terminating when Exit() is called
+ virtual int DoRun();
+
// 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"
-#elif defined(__WXMAC__)
+#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
+#include "wx/stopwatch.h" // for wxMilliClock_t
+
class WXDLLIMPEXP_FWD_CORE wxEventLoopImpl;
class WXDLLIMPEXP_CORE wxGUIEventLoop : public wxEventLoopBase
wxGUIEventLoop() { m_impl = NULL; }
virtual ~wxGUIEventLoop();
- virtual int Run();
- virtual void Exit(int rc = 0);
+ virtual void ScheduleExit(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:
+ virtual int DoRun();
+
// the pointer to the port specific implementation class
wxEventLoopImpl *m_impl;
- DECLARE_NO_COPY_CLASS(wxGUIEventLoop)
+ wxDECLARE_NO_COPY_CLASS(wxGUIEventLoop);
};
#endif // platforms
-// also include the header defining wxConsoleEventLoop for Unix systems
-#if defined(__UNIX__)
- #include "wx/unix/evtloop.h"
-#endif
+#endif // wxUSE_GUI
-// we use a class rather than a typedef because wxEventLoop is forward-declared
-// in many places
#if wxUSE_GUI
+ // we use a class rather than a typedef because wxEventLoop is
+ // forward-declared in many places
class wxEventLoop : public wxGUIEventLoop { };
-#else // !GUI
+#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(__WXMSW__) || defined(__UNIX__))
+ #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
inline bool wxEventLoopBase::IsRunning() const { return GetActive() == this; }
-#if wxUSE_GUI
+#if wxUSE_GUI && !defined(__WXOSX__)
// ----------------------------------------------------------------------------
// wxModalEventLoop
// ----------------------------------------------------------------------------
projects / wxWidgets.git / blobdiff