ardour/libs/pbd/pbd/memento_command.h
2008-12-12 14:43:24 +00:00

101 lines
2.3 KiB
C++

/*
Copyright (C) 2006 Paul Davis
Author: Hans Fugal
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef __lib_pbd_memento_command_h__
#define __lib_pbd_memento_command_h__
#include <iostream>
#include <pbd/command.h>
#include <pbd/stacktrace.h>
#include <pbd/xml++.h>
#include <pbd/shiva.h>
#include <sigc++/slot.h>
#include <typeinfo>
/** This command class is initialized with before and after mementos
* (from Stateful::get_state()), so undo becomes restoring the before
* memento, and redo is restoring the after memento.
*/
template <class obj_T>
class MementoCommand : public Command
{
public:
MementoCommand(obj_T &object, XMLNode *before, XMLNode *after)
: obj(object), before(before), after(after)
{
/* catch destruction of the object */
new PBD::PairedShiva<obj_T,MementoCommand<obj_T> > (object, *this);
}
~MementoCommand ()
{
GoingAway(); /* EMIT SIGNAL */
if (before)
delete before;
if (after)
delete after;
}
void operator() ()
{
if (after)
obj.set_state(*after);
}
void undo()
{
if (before)
obj.set_state(*before);
}
virtual XMLNode &get_state()
{
string name;
if (before && after)
name = "MementoCommand";
else if (before)
name = "MementoUndoCommand";
else
name = "MementoRedoCommand";
XMLNode *node = new XMLNode(name);
node->add_property("obj_id", obj.id().to_s());
node->add_property("type_name", typeid(obj).name());
if (before)
node->add_child_copy(*before);
if (after)
node->add_child_copy(*after);
return *node;
}
protected:
obj_T &obj;
XMLNode *before, *after;
};
#endif // __lib_pbd_memento_h__