IlvActionHistory Class Reference

A repository of user actions. More...

#include <ilviews/base/action.h>

Inheritance diagram for IlvActionHistory:

List of all members.

Public Member Functions
	IlvActionHistory (IlUInt m=8)
	Constructor.
virtual void	add (IlvAction *a)
	Adds an action or a command and executes it (if necessary).
void	addProperty (const IlSymbol *key, IlAny value)
	Adds a property.
virtual IlvAction *	canRepeat ()
	Specifies whether the last executed action can be repeated.
IlvAction *	getAction (IlUInt i) const
	Returns the i th action stored in the history.
IlvValueInterface *const *	getCurrentSelection (IlUInt &c)
	Simplifies access to the current selection in the attached document.
IlvAction *	getLast () const
	Shortcut method for getAction(0).
IlUInt	getLength () const
	Returns the number of actions stored in the history.
IlUInt	getMaxLength () const
	Returns the maximum number of commands that can be stored in the history.
IlAny	getProperty (const IlSymbol *key) const
	Gets a property.
IlvActionSelectionHandler *	getSelectionHandler () const
	Returns the selection handler attached to this history.
IlBoolean	hasProperty (const IlSymbol *key) const
	Property-setting member functions.
virtual void	purge (IlUInt i=(IlUInt)-1)
	Purges the history of recorded actions or commands.
IlBoolean	removeProperty (const IlSymbol *key)
	Removes a property.
virtual void	repeatLast ()
	Repeats the last action stored in the history by duplicating it, executing it, and adding it to the history.
IlBoolean	replaceProperty (const IlSymbol *key, IlAny value)
	Replaces a property.
virtual void	setMaxLength (IlUInt maxLength)
	Sets the maximum number of commands that can be stored in the history.
void	setSelectionHandler (IlvActionSelectionHandler *handler)
	Attaches a selection handler to a history.

---

Detailed Description

A repository of user actions.

Library: views

The class IlvActionHistory defines a repository of user actions. It allows you to implement user feedback, smart repeat, and other advanced input features based on the analysis of the recorded user actions.

See also:

IlvAction, IlvCommand, IlvCommandHistory.

---

Constructor & Destructor Documentation

IlvActionHistory::IlvActionHistory

(

IlUInt

m = 8

)

Constructor.

Parameters:

m

The maximum number of actions that can be recorded in the history.

---

Member Function Documentation

virtual void IlvActionHistory::add

(

IlvAction *

a

)

[virtual]

Adds an action or a command and executes it (if necessary).

If the total number of actions exceeds the maximum number of actions that can be stored in the history, the least recently executed actions are deleted with the delete operator. This means actions added to an action history must be dynamically allocated with the new operator for the action history to keep track of more than one action.

Parameters:

a

The action to be added to the history.

Reimplemented in IlvCommandHistory.

void IlvActionHistory::addProperty	(	const IlSymbol *	key,
		IlAny	value
	)

Adds a property.

See below.

virtual IlvAction* IlvActionHistory::canRepeat

(

)

[virtual]

Specifies whether the last executed action can be repeated.

Returns:

The last executed action if it can be repeated, or 0 if it cannot.

IlvAction* IlvActionHistory::getAction

(

IlUInt

i

)

const

Returns the i ^th action stored in the history.

h.getAction(0) returns the last executed action. h.getAction(h.getLength()-1) returns the earliest executed action still stored in the history.

Parameters:

i

The index of the action to be retrieved.

IlvValueInterface* const* IlvActionHistory::getCurrentSelection

(

IlUInt &

c

)

Simplifies access to the current selection in the attached document.

This method delegates its implementation to the attached IlvActionSelectionHandler object, if any.

IlvAction* IlvActionHistory::getLast

(

)

const

Shortcut method for getAction(0).

Returns:

A pointer to the last action.

IlUInt IlvActionHistory::getLength

(

)

const

Returns the number of actions stored in the history.

Returns:

The number of actions stored in the history.

IlUInt IlvActionHistory::getMaxLength

(

)

const

Returns the maximum number of commands that can be stored in the history.

Returns:

The maximum length of the history stack.

IlAny IlvActionHistory::getProperty

(

const IlSymbol *

key

)

const

Gets a property.

See below.

IlvActionSelectionHandler* IlvActionHistory::getSelectionHandler

(

)

const

Returns the selection handler attached to this history.

Returns:

The selection handler of this history.

IlBoolean IlvActionHistory::hasProperty

(

const IlSymbol *

key

)

const

Property-setting member functions.

Properties can be added to the history through commands or other objects, therefore allowing you to implement smart repeat features.

See also:

IlvPropClassInfo.

virtual void IlvActionHistory::purge

(

IlUInt

i = (IlUInt)-1

)

[virtual]

Purges the history of recorded actions or commands.

Parameters:

i

The number of actions to be removed from the history.

IlBoolean IlvActionHistory::removeProperty

(

const IlSymbol *

key

)

Removes a property.

See below.

virtual void IlvActionHistory::repeatLast

(

)

[virtual]

Repeats the last action stored in the history by duplicating it, executing it, and adding it to the history.

The latest repeatable action stored in the history is repeated.

IlBoolean IlvActionHistory::replaceProperty	(	const IlSymbol *	key,
		IlAny	value
	)

Replaces a property.

See below.

virtual void IlvActionHistory::setMaxLength

(

IlUInt

maxLength

)

[virtual]

Sets the maximum number of commands that can be stored in the history.

Parameters:

maxLength

The maximum length of the history stack.

void IlvActionHistory::setSelectionHandler

(

IlvActionSelectionHandler *

handler

)

Attaches a selection handler to a history.

Parameters:

handler

The selection handler to attach to this history. If this parameter is set to 0, the handler is detached.