mx.data.ItemReference - Adobe® Flex® 4 Language Reference (Flex 4)

Package	mx.data
Class	public dynamic class ItemReference
Inheritance	ItemReference AsyncToken EventDispatcher Object

Language Version:

ActionScript 3.0

Product Version:

LiveCycle Data Services 3

Runtime Versions:

Flash Player 9, AIR 1.1

An ItemReference instance is returned from the DataService.getItem() and DataService.createItem() methods to provide a way to manage a reference to the remote object. The AsyncToken implementation that this class extends provides a list of responders to be notified of result and fault events that occur on the operation to retrieve the item (the get or the create). A binding can be made to the value of the result property that always maintains a reference to the managed instance. If the item is deleted in another client, the result property will be set to null. If a fault occurs and the DatService instance cannot retrieve the item, the invalid property is set to true. Listen for the fault event to get more information about what caused the error.

To release the reference to this managed item, call the ItemReference.releaseItem() method. This is similar to calling the DataService.releaseItem() method however, unlike the DataService.releaseItem() this method releases this reference rather than the first item instance found of that type. This occurs when more than one getItem() method call to retrieve the same item from different parts of an application is made.

Public Properties

Hide Inherited Public Properties

Show Inherited Public Properties

	Property		Defined By
		constructor : Object A reference to the class object or constructor function for a given object instance.	Object
		message : IMessage [read-only] Provides access to the associated message.	AsyncToken
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object
		responders : Array [read-only] An array of IResponder handlers that will be called when the asynchronous request completes.	AsyncToken
		result : Object [read-only] The result that was returned by the associated RPC call.	AsyncToken
		valid : Boolean Set to false if the ItemReference becomes invalid either because the server faulted when trying to retrieve the item or if the retrieved item was itself null.	ItemReference

Public Methods

Hide Inherited Public Methods

Show Inherited Public Methods

	Method		Defined By
		ItemReference(msg:IMessage) Constructor.	ItemReference
		addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.	EventDispatcher
		addResponder(responder:IResponder):void Adds a responder to an Array of responders.	AsyncToken
		dispatchEvent(event:Event):Boolean Dispatches an event into the event flow.	EventDispatcher
		hasEventListener(type:String):Boolean Checks whether the EventDispatcher object has any listeners registered for a specific type of event.	EventDispatcher
		hasOwnProperty(name:String):Boolean Indicates whether an object has a specified property defined.	Object
		hasResponder():Boolean Determines if this token has at least one mx.rpc.IResponder registered.	AsyncToken
		isPrototypeOf(theClass:Object):Boolean Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.	Object
		propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable.	Object
		releaseItem(copyStillManagedItems:Boolean = true, enableStillManagedCheck:Boolean = true):void Releases the managed item reference retrieved with the getItem() or createItem() method call that returned this ItemReference.	ItemReference
		removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void Removes a listener from the EventDispatcher object.	EventDispatcher
		setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations.	Object
		toLocaleString():String Returns the string representation of this object, formatted according to locale-specific conventions.	Object
		toString():String Returns the string representation of the specified object.	Object
		valueOf():Object Returns the primitive value of the specified object.	Object
		willTrigger(type:String):Boolean Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.	EventDispatcher

Events

Click for more information on events

Hide Inherited Events

Show Inherited Events

	Summary	Defined By
activate	[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.	EventDispatcher
deactivate	[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.	EventDispatcher
propertyChange	Dispatched when a property of the channel set changes.	AsyncToken

Property Detail

valid

property

valid:Boolean

Language Version:

ActionScript 3.0

Product Version:

LiveCycle Data Services 3

Runtime Versions:

Flash Player 9, AIR 1.1

Set to false if the ItemReference becomes invalid either because the server faulted when trying to retrieve the item or if the retrieved item was itself null. This property can be used to bind to your user interface controls to display status information for this item without having to listen for explicit fault events.

This property can be used as the source for data binding. When this property is modified, it dispatches the propertyChange event.

Implementation
public function get valid():Boolean
public function set valid(value:Boolean):void

Constructor Detail

ItemReference

()

Constructor

public function ItemReference(msg:IMessage)

Language Version:

ActionScript 3.0

Product Version:

LiveCycle Data Services 3

Runtime Versions:

Flash Player 9, AIR 1.1

Constructor.

Parameters

msg:IMessage — A message object.

Method Detail

releaseItem

()

method

public function releaseItem(copyStillManagedItems:Boolean = true, enableStillManagedCheck:Boolean = true):void

Language Version:

ActionScript 3.0

Product Version:

LiveCycle Data Services 3

Runtime Versions:

Flash Player 9, AIR 1.1

Releases the managed item reference retrieved with the getItem() or createItem() method call that returned this ItemReference. It is possible to have more than one ItemReference that points to the same item on the same client. Use this method to release the proper reference.

Parameters

	`copyStillManagedItems:Boolean` (default = `true`) — Boolean indicating that a copy of this item should be placed in this ItemReference should the current item still be referenced. This can occur if more than one call to `DataService.gteItem()` for this same item is made, or if this item is referenced by a collection returned from a call to `DataService.fill()`.

	`enableStillManagedCheck:Boolean` (default = `true`)