FX::FXCommand Class Reference

Base class for undoable commands. More...

#include <FXUndoList.h>

Inheritance diagram for FX::FXCommand:

List of all members.

Public Member Functions
virtual void	undo ()=0
virtual void	redo ()=0
virtual FXuint	size () const
virtual FXString	undoName () const
virtual FXString	redoName () const
virtual bool	canMerge () const
virtual bool	mergeWith (FXCommand *command)
virtual	~FXCommand ()
Friends
class	FXUndoList
class	FXCommandGroup

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Detailed Description

Base class for undoable commands.

Each undo records all the information necessary to undo as well as redo a given operation. Since commands are derived from FXObject, subclassed commands can both send and receive messages (like ID_GETINTVALUE, for example).

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Constructor & Destructor Documentation

virtual FX::FXCommand::~FXCommand (   )  [inline, virtual]

Delete undo command.

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Member Function Documentation

virtual void FX::FXCommand::undo (   )  [pure virtual]

Undo this command; this should save the information for a subsequent redo. Implemented in FX::FXCommandGroup, and FX::FXUndoList.

virtual void FX::FXCommand::redo (   )  [pure virtual]

Redo this command; this should save the information for a subsequent undo. Implemented in FX::FXCommandGroup, and FX::FXUndoList.

virtual FXuint FX::FXCommand::size (   )  const [virtual]

Return the size of the information in the undo record. The undo list may be trimmed to limit memory usage to a certain limit. The value returned should include the size of the command record itself as well as any data linked from it. Reimplemented in FX::FXCommandGroup, and FX::FXUndoList.

virtual FXString FX::FXCommand::undoName (   )  const [virtual]

Name of the undo command to be shown on a button; for example, "Undo Delete". Reimplemented in FX::FXUndoList.

virtual FXString FX::FXCommand::redoName (   )  const [virtual]

Name of the redo command to be shown on a button; for example, "Redo Delete". Reimplemented in FX::FXUndoList.

virtual bool FX::FXCommand::canMerge (   )  const [virtual]

Return TRUE if this command can be merged with previous undo commands. This is useful to combine e.g. multiple consecutive single-character text changes into a single block change. The default implementation returns FALSE.

virtual bool FX::FXCommand::mergeWith (  FXCommand *  command  )  [virtual]

Called by the undo system to try and merge the new incoming command with this command; should return TRUE if merging was possible. The default implementation returns FALSE.

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Friends And Related Function Documentation

friend class FXUndoList [friend]

Reimplemented in FX::FXCommandGroup.

friend class FXCommandGroup [friend]

Copyright © 1997-2005 Jeroen van der Zijp