From cf2227623a889dd0a5f36288d346fc6bf64b55fa Mon Sep 17 00:00:00 2001 From: Vadim Zeitlin Date: Tue, 23 Oct 2012 12:02:24 +0000 Subject: [PATCH] Add wxEvtHandler::CallAfter() for asynchronous method calls. Add wxAsyncMethodCallEvent that is handled simply by calling the method this event was created for and add default handler for this event to wxEvtHandler. Implement CallAfter() overloads for up to 2 parameters only for now. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72722 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775 --- docs/changes.txt | 1 + include/wx/event.h | 197 ++++++++++++++++++++++++++++++++++++++++++- interface/wx/event.h | 47 +++++++++++ src/common/event.cpp | 12 ++- 4 files changed, 255 insertions(+), 2 deletions(-) diff --git a/docs/changes.txt b/docs/changes.txt index 095511a1d9..4bd6cef11f 100644 --- a/docs/changes.txt +++ b/docs/changes.txt @@ -529,6 +529,7 @@ Major new features in this release All: +- Add wxEvtHandler::CallAfter() method for asynchronous method calls. - Add support for symlinks to wxFileName (David Hart). - Allow testing for symlink/FIFO/socket existence in wxFileName (David Hart). - Many important bug fixes in wxFileSystemWatcher (David Hart). diff --git a/include/wx/event.h b/include/wx/event.h index 5db787ce6c..e28d5c2970 100644 --- a/include/wx/event.h +++ b/include/wx/event.h @@ -33,6 +33,8 @@ #include "wx/meta/convertible.h" #endif +#include "wx/meta/removeref.h" + // ---------------------------------------------------------------------------- // forward declarations // ---------------------------------------------------------------------------- @@ -621,6 +623,7 @@ extern WXDLLIMPEXP_BASE const wxEventType wxEVT_USER_FIRST; // Need events declared to do this class WXDLLIMPEXP_FWD_BASE wxIdleEvent; class WXDLLIMPEXP_FWD_BASE wxThreadEvent; +class WXDLLIMPEXP_FWD_BASE wxAsyncMethodCallEvent; class WXDLLIMPEXP_FWD_CORE wxCommandEvent; class WXDLLIMPEXP_FWD_CORE wxMouseEvent; class WXDLLIMPEXP_FWD_CORE wxFocusEvent; @@ -681,8 +684,9 @@ wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_CORE, wxEVT_COMMAND_TOOL_ENTER, wxCommandEv wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_CORE, wxEVT_COMMAND_COMBOBOX_DROPDOWN, wxCommandEvent); wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_CORE, wxEVT_COMMAND_COMBOBOX_CLOSEUP, wxCommandEvent); - // Thread events + // Thread and asynchronous method call events wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_BASE, wxEVT_THREAD, wxThreadEvent); +wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_BASE, wxEVT_ASYNC_METHOD_CALL, wxAsyncMethodCallEvent); // Mouse event types wxDECLARE_EXPORTED_EVENT(WXDLLIMPEXP_CORE, wxEVT_LEFT_DOWN, wxMouseEvent); @@ -1266,6 +1270,159 @@ private: }; +// Asynchronous method call events: these event are processed by wxEvtHandler +// itself and result in a call to its Execute() method which simply calls the +// specified method. The difference with a simple method call is that this is +// done asynchronously, i.e. at some later time, instead of immediately when +// the event object is constructed. + +// This is a base class used to process all method calls. +class wxAsyncMethodCallEvent : public wxEvent +{ +public: + wxAsyncMethodCallEvent(wxObject* object) + : wxEvent(wxID_ANY, wxEVT_ASYNC_METHOD_CALL) + { + SetEventObject(object); + } + + wxAsyncMethodCallEvent(const wxAsyncMethodCallEvent& other) + : wxEvent(other) + { + } + + virtual void Execute() = 0; +}; + +// This is a version for calling methods without parameters. +template +class wxAsyncMethodCallEvent0 : public wxAsyncMethodCallEvent +{ +public: + typedef T ObjectType; + typedef void (ObjectType::*MethodType)(); + + wxAsyncMethodCallEvent0(ObjectType* object, + MethodType method) + : wxAsyncMethodCallEvent(object), + m_object(object), + m_method(method) + { + } + + wxAsyncMethodCallEvent0(const wxAsyncMethodCallEvent0& other) + : wxAsyncMethodCallEvent(other), + m_object(other.m_object), + m_method(other.m_method) + { + } + + virtual wxEvent *Clone() const + { + return new wxAsyncMethodCallEvent0(*this); + } + + virtual void Execute() + { + (m_object->*m_method)(); + } + +private: + ObjectType* const m_object; + const MethodType m_method; +}; + +// This is a version for calling methods with a single parameter. +template +class wxAsyncMethodCallEvent1 : public wxAsyncMethodCallEvent +{ +public: + typedef T ObjectType; + typedef void (ObjectType::*MethodType)(T1 x1); + typedef typename wxRemoveRef::type ParamType1; + + wxAsyncMethodCallEvent1(ObjectType* object, + MethodType method, + const ParamType1& x1) + : wxAsyncMethodCallEvent(object), + m_object(object), + m_method(method), + m_param1(x1) + { + } + + wxAsyncMethodCallEvent1(const wxAsyncMethodCallEvent1& other) + : wxAsyncMethodCallEvent(other), + m_object(other.m_object), + m_method(other.m_method), + m_param1(other.m_param1) + { + } + + virtual wxEvent *Clone() const + { + return new wxAsyncMethodCallEvent1(*this); + } + + virtual void Execute() + { + (m_object->*m_method)(m_param1); + } + +private: + ObjectType* const m_object; + const MethodType m_method; + const ParamType1 m_param1; +}; + +// This is a version for calling methods with two parameters. +template +class wxAsyncMethodCallEvent2 : public wxAsyncMethodCallEvent +{ +public: + typedef T ObjectType; + typedef void (ObjectType::*MethodType)(T1 x1, T2 x2); + typedef typename wxRemoveRef::type ParamType1; + typedef typename wxRemoveRef::type ParamType2; + + wxAsyncMethodCallEvent2(ObjectType* object, + MethodType method, + const ParamType1& x1, + const ParamType2& x2) + : wxAsyncMethodCallEvent(object), + m_object(object), + m_method(method), + m_param1(x1), + m_param2(x2) + { + } + + wxAsyncMethodCallEvent2(const wxAsyncMethodCallEvent2& other) + : wxAsyncMethodCallEvent(other), + m_object(other.m_object), + m_method(other.m_method), + m_param1(other.m_param1), + m_param2(other.m_param2) + { + } + + virtual wxEvent *Clone() const + { + return new wxAsyncMethodCallEvent2(*this); + } + + virtual void Execute() + { + (m_object->*m_method)(m_param1, m_param2); + } + +private: + ObjectType* const m_object; + const MethodType m_method; + const ParamType1 m_param1; + const ParamType2 m_param2; +}; + #if wxUSE_GUI @@ -3137,6 +3294,44 @@ public: // NOTE: uses AddPendingEvent(); call only from secondary threads #endif + // Asynchronous method calls: these methods schedule the given method + // pointer for a later call (during the next idle event loop iteration). + // + // Notice that the method is called on this object itself, so the object + // CallAfter() is called on must have the correct dynamic type. + // + // These method can be used from another thread. + + template + void CallAfter(void (T::*method)()) + { + QueueEvent( + new wxAsyncMethodCallEvent0(static_cast(this), method) + ); + } + + // Notice that we use P1 and not T1 for the parameter to allow passing + // parameters that are only convertible to the type taken by the method + // instead of being exactly the same, to be closer to the usual method call + // semantics. + template + void CallAfter(void (T::*method)(T1 x1), P1 x1) + { + QueueEvent( + new wxAsyncMethodCallEvent1( + static_cast(this), method, x1) + ); + } + + template + void CallAfter(void (T::*method)(T1 x1, T2 x2), P1 x1, P2 x2) + { + QueueEvent( + new wxAsyncMethodCallEvent2( + static_cast(this), method, x1, x2) + ); + } + // Connecting and disconnecting // ---------------------------- diff --git a/interface/wx/event.h b/interface/wx/event.h index 3946f05f99..3aae72f4a1 100644 --- a/interface/wx/event.h +++ b/interface/wx/event.h @@ -477,6 +477,53 @@ public: */ virtual void AddPendingEvent(const wxEvent& event); + /** + Asynchronously call the given method. + + Calling this function on an object schedules an asynchronous call to + the method specified as CallAfter() argument at a (slightly) later + time. This is useful when processing some events as certain actions + typically can't be performed inside their handlers, e.g. you shouldn't + show a modal dialog from a mouse click event handler as this would + break the mouse capture state -- but you can call a method showing + this message dialog after the current event handler completes. + + The method being called must be the method of the object on which + CallAfter() itself is called. + + Notice that it is safe to use CallAfter() from other, non-GUI, + threads, but that the method will be always called in the main, GUI, + thread context. + + Example of use: + @code + class MyFrame : public wxFrame { + void OnClick(wxMouseEvent& event) { + CallAfter(&MyFrame::ShowPosition, event.GetPosition()); + } + + void ShowPosition(const wxPoint& pos) { + if ( wxMessageBox( + wxString::Format("Perform click at (%d, %d)?", + pos.x, pos.y), "", wxYES_NO) == wxYES ) + { + ... do take this click into account ... + } + } + }; + @endcode + + @param method The method to call. + @param x1 The (optional) first parameter to pass to the method. + @param x2 The (optional) second parameter to pass to the method. + + Note that currently only up to 2 arguments can be passed. + + @since 2.9.5 + */ + template + void CallAfter(void (T::*method)(T1, ...), T1 x1, ...); + /** Processes an event, searching event tables and calling zero or more suitable event handler function(s). diff --git a/src/common/event.cpp b/src/common/event.cpp index fa39ae924b..07e5fc3341 100644 --- a/src/common/event.cpp +++ b/src/common/event.cpp @@ -156,8 +156,9 @@ const wxEventType wxEVT_NULL = wxNewEventType(); wxDEFINE_EVENT( wxEVT_IDLE, wxIdleEvent ); -// Thread event +// Thread and asynchronous call events wxDEFINE_EVENT( wxEVT_THREAD, wxThreadEvent ); +wxDEFINE_EVENT( wxEVT_ASYNC_METHOD_CALL, wxAsyncMethodCallEvent ); #endif // wxUSE_BASE @@ -1564,6 +1565,15 @@ bool wxEvtHandler::TryHereOnly(wxEvent& event) if ( GetEventHashTable().HandleEvent(event, this) ) return true; + // There is an implicit entry for async method calls procession in every + // event handler: + if ( event.GetEventType() == wxEVT_ASYNC_METHOD_CALL && + event.GetEventObject() == this ) + { + static_cast(event).Execute(); + return true; + } + // We don't have a handler for this event. return false; } -- 2.47.2