wxWidgets/include/wx/eventfilter.h
Dimitri Schoolwerth d9384bfb6d no code changes, fixed some typos
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70302 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
2012-01-09 14:04:25 +00:00

73 lines
2.2 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Name: wx/eventfilter.h
// Purpose: wxEventFilter class declaration.
// Author: Vadim Zeitlin
// Created: 2011-11-21
// RCS-ID: $Id$
// Copyright: (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
#ifndef _WX_EVENTFILTER_H_
#define _WX_EVENTFILTER_H_
#include "wx/defs.h"
class WXDLLIMPEXP_FWD_BASE wxEvent;
class WXDLLIMPEXP_FWD_BASE wxEvtHandler;
// ----------------------------------------------------------------------------
// wxEventFilter is used with wxEvtHandler::AddFilter() and ProcessEvent().
// ----------------------------------------------------------------------------
class wxEventFilter
{
public:
// Possible return values for FilterEvent().
//
// Notice that the values of these enum elements are fixed due to backwards
// compatibility constraints.
enum
{
// Process event as usual.
Event_Skip = -1,
// Don't process the event normally at all.
Event_Ignore = 0,
// Event was already handled, don't process it normally.
Event_Processed = 1
};
wxEventFilter()
{
m_next = NULL;
}
virtual ~wxEventFilter()
{
wxASSERT_MSG( !m_next, "Forgot to call wxEvtHandler::RemoveFilter()?" );
}
// This method allows to filter all the events processed by the program, so
// you should try to return quickly from it to avoid slowing down the
// program to a crawl.
//
// Return value should be -1 to continue with the normal event processing,
// or true or false to stop further processing and pretend that the event
// had been already processed or won't be processed at all, respectively.
virtual int FilterEvent(wxEvent& event) = 0;
private:
// Objects of this class are made to be stored in a linked list in
// wxEvtHandler so put the next node ponter directly in the class itself.
wxEventFilter* m_next;
// And provide access to it for wxEvtHandler [only].
friend class wxEvtHandler;
wxDECLARE_NO_COPY_CLASS(wxEventFilter);
};
#endif // _WX_EVENTFILTER_H_