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second part of #10320: move wxApp event handling functions to wxEventLoopBase (in particular move Yield() functions); add backward compatible redirections to wxApp; update docs; remove global lists wxPendingEvents and wxPendingEventsLocker

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git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58911 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
This commit is contained in:
Francesco Montorsi
2009-02-15 14:25:08 +00:00
parent 145bbf1fdf
commit dde19c2180
50 changed files with 1104 additions and 1070 deletions
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148
include/wx/evtloop.h
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@@ -14,6 +14,36 @@
#include "wx/utils.h"
/*
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
// ----------------------------------------------------------------------------
@@ -22,7 +52,7 @@ class WXDLLIMPEXP_BASE wxEventLoopBase
{
public:
// trivial, but needed (because of wxEventLoopBase) ctor
wxEventLoopBase() { }
wxEventLoopBase();
// dtor
virtual ~wxEventLoopBase() { }
@@ -32,9 +62,18 @@ public:
virtual bool IsOk() const { return true; }
// 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;
@@ -49,6 +88,86 @@ public:
// 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;
// pending events
// --------------
// process all events in the wxHandlersWithPendingEvents list -- it is necessary
// to call this function to process posted events. This happens during each
// event loop iteration in GUI mode but if there is no main loop, it may be
// also called directly.
virtual void ProcessPendingEvents();
// check if there are pending events on global pending event list
bool HasPendingEvents() const;
// temporary suspends processing of the pending events
void SuspendProcessingOfPendingEvents();
// resume processing of the pending events previously stopped because of a
// call to SuspendProcessingOfPendingEvents()
void ResumeProcessingOfPendingEvents();
// called by ~wxEvtHandler to (eventually) remove the handler from the list of
// the handlers with pending events
void RemovePendingEventHandler(wxEvtHandler* toRemove);
// adds an event handler to the list of the handlers with pending events
void AppendPendingEventHandler(wxEvtHandler* toAppend);
// moves the event handler from the list of the handlers with pending events
//to the list of the handlers with _delayed_ pending events
void DelayPendingEventHandler(wxEvtHandler* toDelay);
// idle handling
// -------------
// make sure that idle events are sent again
virtual void WakeUpIdle();
// this virtual function is called when the application
// becomes idle and normally just sends wxIdleEvent to all interested
// parties
//
// 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; }
@@ -56,15 +175,6 @@ public:
// set currently active (running) event loop
static void SetActive(wxEventLoopBase* loop) { ms_activeLoop = 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:
// this function should be called before the event loop terminates, whether
@@ -72,10 +182,25 @@ protected:
// an exception thrown from inside the loop)
virtual void OnExit() { }
// the pointer to currently active loop
static wxEventLoopBase *ms_activeLoop;
// the array of the handlers with pending events which needs to be processed
// inside ProcessPendingEvents()
wxEvtHandlerArray m_handlersWithPendingEvents;
// helper array used by ProcessPendingEvents()
wxEvtHandlerArray m_handlersWithPendingDelayedEvents;
#if wxUSE_THREADS
// this critical section protects both the lists above
wxCriticalSection m_handlersWithPendingEventsLocker;
#endif
// Yield() helpers:
bool m_isInsideYield;
long m_eventsToProcessInsideYield;
wxDECLARE_NO_COPY_CLASS(wxEventLoopBase);
};
@@ -161,6 +286,7 @@ public:
}
}
virtual void WakeUp() { }
virtual bool YieldFor(long eventsToProcess);
protected:
// the pointer to the port specific implementation class