dolphin/Externals/wxWidgets3/include/wx/tracker.h

93 lines
2.6 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: wx/tracker.h
// Purpose: Support class for object lifetime tracking (wxWeakRef<T>)
// Author: Arne Steinarson
// Created: 28 Dec 07
// RCS-ID: $Id: tracker.h 51448 2008-01-29 17:41:10Z RD $
// Copyright: (c) 2007 Arne Steinarson
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
#ifndef _WX_TRACKER_H_
#define _WX_TRACKER_H_
#include "wx/defs.h"
class wxEventConnectionRef;
// This class represents an object tracker and is stored in a linked list
// in the tracked object. It is only used in one of its derived forms.
class WXDLLIMPEXP_BASE wxTrackerNode
{
public:
wxTrackerNode() : m_nxt(NULL) { }
virtual ~wxTrackerNode() { }
virtual void OnObjectDestroy() = 0;
virtual wxEventConnectionRef *ToEventConnection() { return NULL; }
private:
wxTrackerNode *m_nxt;
friend class wxTrackable; // For list access
friend class wxEvtHandler; // For list access
};
// Add-on base class for a trackable object.
class WXDLLIMPEXP_BASE wxTrackable
{
public:
void AddNode(wxTrackerNode *prn)
{
prn->m_nxt = m_first;
m_first = prn;
}
void RemoveNode(wxTrackerNode *prn)
{
for ( wxTrackerNode **pprn = &m_first; *pprn; pprn = &(*pprn)->m_nxt )
{
if ( *pprn == prn )
{
*pprn = prn->m_nxt;
return;
}
}
wxFAIL_MSG( "removing invalid tracker node" );
}
wxTrackerNode *GetFirst() const { return m_first; }
protected:
// this class is only supposed to be used as a base class but never be
// created nor destroyed directly so all ctors and dtor are protected
wxTrackable() : m_first(NULL) { }
// copy ctor and assignment operator intentionally do not copy m_first: the
// objects which track the original trackable shouldn't track the new copy
wxTrackable(const wxTrackable& WXUNUSED(other)) : m_first(NULL) { }
wxTrackable& operator=(const wxTrackable& WXUNUSED(other)) { return *this; }
// dtor is not virtual: this class is not supposed to be used
// polymorphically and adding a virtual table to it would add unwanted
// overhead
~wxTrackable()
{
// Notify all registered refs
while ( m_first )
{
wxTrackerNode * const first = m_first;
m_first = first->m_nxt;
first->OnObjectDestroy();
}
}
wxTrackerNode *m_first;
};
#endif // _WX_TRACKER_H_