edu.ucdavis.cstars.client

Class UndoManager

java.lang.Object

com.google.gwt.core.client.JavaScriptObject

edu.ucdavis.cstars.client.UndoManager

public class UndoManager
extends com.google.gwt.core.client.JavaScriptObject

The Undo Manager is a utility object that allows you to easily build applications with undo/redo functionality. Use the Undo Manager to add operations (edits, navigation changes, graphics drawing) to the stack. The API includes a set of edit operations (add,delete,update, cut and union), created by inherting from the OperationBase class. You can inherit from the OperationBase class to create custom operations that take advantage of undo/redo.

Author:

Justin Merz

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UndoManager.Options

Method Summary

Methods

Modifier and Type	Method and Description
void	add(OperationBase operation) Adds an undo operation to the stack and clears the redo stack.
void	addAddHandler(UndoManagerAddHandler handler) Add handler for when operation is added
void	addChangeHandler(UndoManagerChangeHandler handler) Add handler for when stack changes.
void	addRedoHandler(UndoManagerRedoHandler handler) Add handler for redo operation
void	addUndoHandler(UndoManagerUndoHandler handler) Add handler for undo operation
static boolean	assertLoaded() Check that the esri.undoManager has been loaded
boolean	canRedo() When true, there are redo operations available on the stack.
boolean	canUndo() When true, there are undo operations available on the stack
void	clearRedo() clear the redo stack
void	clearUndo() clear the undo stack
static UndoManager	create(UndoManager.Options options) Creates a new UndoManager object.
void	destroy() Destroy the operation manager.
OperationBase	get(int operationId) Get the specified operation from the stack.
int	getLength() The number of operations stored in the history stack.
OperationBase	peekRedo() Get the next redo operation from the stack
OperationBase	peekUndo() Get the next undo operation from the stack.
int	position() The current operation position.
void	redo() Moves the current position to the next redo operation and calls the operation's performRedo() method.
OperationBase	remove(int operationId) Remove the specified operation from the stack.
void	undo() Moves the current position to the next undo operation and calls the operation's performUndo method.

Methods inherited from class com.google.gwt.core.client.JavaScriptObject

cast, createArray, createArray, createFunction, createObject, equals, hashCode, toSource, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Method Detail

create

public static UndoManager create(UndoManager.Options options)

Creates a new UndoManager object.

Parameters:

options -

Returns:

UndoManager

assertLoaded

public static boolean assertLoaded()

Check that the esri.undoManager has been loaded

Returns:

boolean

canRedo

public final boolean canRedo()

When true, there are redo operations available on the stack.

Returns:

boolean

canUndo

public final boolean canUndo()

When true, there are undo operations available on the stack

Returns:

boolean

getLength

public final int getLength()

The number of operations stored in the history stack.

Returns:

int

position

public final int position()

The current operation position. A position value of 0 means that no operations are available on the stack. When an undo operation is performed the position decreases by 1. When a redo occurs the position is incremented by 1.

Returns:

int

add

public final void add(OperationBase operation)

Adds an undo operation to the stack and clears the redo stack.

Parameters:

operation - - operation to add.

clearRedo

public final void clearRedo()

clear the redo stack

clearUndo

public final void clearUndo()

clear the undo stack

destroy

public final void destroy()

Destroy the operation manager. Sets the history stack to null and cleans up all references.

get

public final OperationBase get(int operationId)

Get the specified operation from the stack.

Parameters:

operationId - - the operation id.

Returns:

OperationBase

peekRedo

public final OperationBase peekRedo()

Get the next redo operation from the stack

Returns:

OperationBase

peekUndo

public final OperationBase peekUndo()

Get the next undo operation from the stack.

Returns:

OperationBase

redo

public final void redo()

Moves the current position to the next redo operation and calls the operation's performRedo() method.

remove

public final OperationBase remove(int operationId)

Remove the specified operation from the stack.

Parameters:

operationId - - the operation id

Returns:

OperationBase

undo

public final void undo()

Moves the current position to the next undo operation and calls the operation's performUndo method.

addAddHandler

public final void addAddHandler(UndoManagerAddHandler handler)

Add handler for when operation is added

Parameters:

handler - - Fires when the add method is called to add an operation is added to the stack.

addChangeHandler

public final void addChangeHandler(UndoManagerChangeHandler handler)

Add handler for when stack changes.

Parameters:

handler - - Fires when the undo/redo stack changes.

addRedoHandler

public final void addRedoHandler(UndoManagerRedoHandler handler)

Add handler for redo operation

Parameters:

handler - - Fires when the redo method is called.

addUndoHandler

public final void addUndoHandler(UndoManagerUndoHandler handler)

Add handler for undo operation

Parameters:

handler - - Fires when the undo method is called.