void SetEvtHandlerEnabled(bool enabled) { m_enabled = enabled; }
bool GetEvtHandlerEnabled() const { return m_enabled; }
- // process an event right now
+ // Process an event right now: this can only be called from the main
+ // thread, use QueueEvent() for scheduling the events for
+ // processing from other threads.
virtual bool ProcessEvent(wxEvent& event);
// Process an event by calling ProcessEvent and handling any exceptions
// wouldn't correctly propagate to wxEventLoop.
bool SafelyProcessEvent(wxEvent& event);
- // add an event to be processed later
- virtual void AddPendingEvent(const wxEvent& event);
+ // Schedule the given event to be processed later. It takes ownership of
+ // the event pointer, i.e. it will be deleted later. This is safe to call
+ // from multiple threads although you still need to ensure that wxString
+ // fields of the event object are deep copies and not use the same string
+ // buffer as other wxString objects in this thread.
+ virtual void QueueEvent(wxEvent *event);
+
+ // Add an event to be processed later: notice that this function is not
+ // safe to call from threads other than main, use QueueEvent()
+ virtual void AddPendingEvent(const wxEvent& event)
+ {
+ // notice that the thread-safety problem comes from the fact that
+ // Clone() doesn't make deep copies of wxString fields of wxEvent
+ // object and so the same wxString could be used from both threads when
+ // the event object is destroyed in this one -- QueueEvent() avoids
+ // this problem as the event pointer is not used any more in this
+ // thread at all after it is called.
+ QueueEvent(event.Clone());
+ }
void ProcessPendingEvents();
};
#endif // wxUSE_WEAKREF
-// Post a message to the given eventhandler which will be processed during the
-// next event loop iteration
+// Post a message to the given event handler which will be processed during the
+// next event loop iteration.
+//
+// Notice that this one is not thread-safe, use wxQueueEvent()
inline void wxPostEvent(wxEvtHandler *dest, const wxEvent& event)
{
- wxCHECK_RET( dest, wxT("need an object to post event to in wxPostEvent") );
+ wxCHECK_RET( dest, "need an object to post event to" );
dest->AddPendingEvent(event);
}
+// Wrapper around wxEvtHandler::QueueEvent(): adds an event for later
+// processing, unlike wxPostEvent it is safe to use from different thread even
+// for events with wxString members
+inline void wxQueueEvent(wxEvtHandler *dest, wxEvent *event)
+{
+ wxCHECK_RET( dest, "need an object to queue event for" );
+
+ dest->QueueEvent(event);
+}
+
typedef void (wxEvtHandler::*wxEventFunction)(wxEvent&);
typedef void (wxEvtHandler::*wxIdleEventFunction)(wxIdleEvent&);