Adobe® Flex® 4 Language Reference
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mx.utils 
ObjectProxy 
Packagemx.utils
Classpublic dynamic class ObjectProxy
InheritanceObjectProxy Inheritance Proxy Inheritance Object
Implements IExternalizable, IPropertyChangeNotifier
Subclasses ManagedObjectProxy

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

This class provides the ability to track changes to an item managed by this proxy. Any number of objects can "listen" for changes on this object, by using the addEventListener() method.



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  uid : String
The unique identifier for this object.
ObjectProxy
Protected Properties
 PropertyDefined By
  dispatcher : EventDispatcher
A reference to the EventDispatcher for this proxy.
ObjectProxy
  notifiers : Object
A hashmap of property change notifiers that this proxy is listening for changes from; the key of the map is the property name.
ObjectProxy
  object : Object
[read-only] The object being proxied.
ObjectProxy
  propertyList : Array
Contains a list of all of the property names for the proxied object.
ObjectProxy
  proxyClass : Class
Indicates what kind of proxy to create when proxying complex properties.
ObjectProxy
  type : QName
The qualified type name associated with this object.
ObjectProxy
Public Methods
 MethodDefined By
  
ObjectProxy(item:Object = null, uid:String = null, proxyDepth:int = -1)
Initializes this proxy with the specified object, id and proxy depth.
ObjectProxy
  
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object so that the listener receives notification of an event.
ObjectProxy
  
Dispatches an event into the event flow.
ObjectProxy
  
Checks whether there are any event listeners registered for a specific type of event.
ObjectProxy
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
  
Called when a complex property is updated.
ObjectProxy
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
  
Since Flex only uses ObjectProxy to wrap anonymous objects, the server flex.messaging.io.ObjectProxy instance serializes itself as a Map that will be returned as a plain ActionScript object.
ObjectProxy
  
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes an event listener.
ObjectProxy
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
  
Checks whether an event listener is registered with this object or any of its ancestors for the specified event type.
ObjectProxy
  
Since Flex only serializes the inner ActionScript object that it wraps, the server flex.messaging.io.ObjectProxy populates itself with this anonymous object's contents and appears to the user as a Map.
ObjectProxy
Protected Methods
 MethodDefined By
  
callProperty(name:*, ... rest):*
[override] Returns the value of the proxied object's method with the specified name.
ObjectProxy
  
[override] Deletes the specified property on the proxied object and sends notification of the delete to the handler.
ObjectProxy
  
getComplexProperty(name:*, value:*):*
Provides a place for subclasses to override how a complex property that needs to be either proxied or daisy chained for event bubbling is managed.
ObjectProxy
  
[override] Returns the specified property value of the proxied object.
ObjectProxy
  
setProperty(name:*, value:*):void
[override] Updates the specified property on the proxied object and sends notification of the update to the handler.
ObjectProxy
  
This method creates an array of all of the property names for the proxied object.
ObjectProxy
Property Detail

dispatcher

property
protected var dispatcher:EventDispatcher

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

A reference to the EventDispatcher for this proxy.

notifiers

property 
protected var notifiers:Object

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

A hashmap of property change notifiers that this proxy is listening for changes from; the key of the map is the property name.

object

property 
object:Object  [read-only]

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

The object being proxied.



Implementation
    object_proxy function get object():Object

propertyList

property 
protected var propertyList:Array

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Contains a list of all of the property names for the proxied object. Descendants need to fill this list by overriding the setupPropertyList() method.

proxyClass

property 
protected var proxyClass:Class

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Indicates what kind of proxy to create when proxying complex properties. Subclasses should assign this value appropriately.

type

property 
type:QName

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

The qualified type name associated with this object.



Implementation
    object_proxy function get type():QName
    object_proxy function set type(value:QName):void

uid

property 
uid:String

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

The unique identifier for this object.



Implementation
    public function get uid():String
    public function set uid(value:String):void
Constructor Detail

ObjectProxy

()Constructor
public function ObjectProxy(item:Object = null, uid:String = null, proxyDepth:int = -1)

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Initializes this proxy with the specified object, id and proxy depth.

Parameters
item:Object (default = null) — Object to proxy. If no item is specified, an anonymous object will be constructed and assigned.
 
uid:String (default = null) — String containing the unique id for this object instance. Required for IPropertyChangeNotifier compliance as every object must provide a unique way of identifying it. If no value is specified, a random id will be assigned.
 
proxyDepth:int (default = -1) — An integer indicating how many levels in a complex object graph should have a proxy created during property access. The default is -1, meaning "proxy to infinite depth".

Example
How to use this example
      import mx.events.PropertyChangeEvent;
      import mx.utils.ObjectUtil;
      import mx.utils.ObjectProxy;
      import mx.utils.StringUtil;
     
      var a:Object = { name: "Tyler", age: 5, ssnum: "555-55-5555" };
      var p:ObjectProxy = new ObjectProxy(a);
      p.addEventListener(PropertyChangeEvent.PROPERTY_CHANGE, updateHandler);
      p.name = "Jacey";
      p.age = 2;
      delete p.ssnum;
     
      // handler function
      function updateHandler(event:PropertyChangeEvent):void
      {
          trace(StringUtil.substitute("updateHandler('{0}', {1}, {2}, {3}, '{4}')",
                                         event.kind,
                                         event.property,
                                         event.oldValue,
                                         event.newValue,
                                         event.target.uid));
      }
     
      // trace output
      updateHandler('opUpdate', name, Jacey, '698AF8CB-B3D9-21A3-1AFFDGHT89075CD2')
      updateHandler('opUpdate', age, 2, '698AF8CB-B3D9-21A3-1AFFDGHT89075CD2')
      updateHandler('opDelete', ssnum, null, '698AF8CB-B3D9-21A3-1AFFDGHT89075CD2')
      
Method Detail

addEventListener

()method
public function addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Registers an event listener object so that the listener receives notification of an event. For more information, including descriptions of the parameters see addEventListener() in the flash.events.EventDispatcher class.

Parameters

type:String
 
listener:Function
 
useCapture:Boolean (default = false)
 
priority:int (default = 0)
 
useWeakReference:Boolean (default = false)

See also

callProperty

()method 
override flash_proxy function callProperty(name:*, ... rest):*

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Returns the value of the proxied object's method with the specified name.

Parameters

name:* — The name of the method being invoked.
 
... rest — An array specifying the arguments to the called method.

Returns
* — The return value of the called method.

deleteProperty

()method 
override flash_proxy function deleteProperty(name:*):Boolean

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Deletes the specified property on the proxied object and sends notification of the delete to the handler.

Parameters

name:* — Typically a string containing the name of the property, or possibly a QName where the property name is found by inspecting the localName property.

Returns
Boolean — A Boolean indicating if the property was deleted.

dispatchEvent

()method 
public function dispatchEvent(event:Event):Boolean

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Dispatches an event into the event flow. For more information, see the flash.events.EventDispatcher class.

Parameters

event:Event — The Event object that is dispatched into the event flow. If the event is being redispatched, a clone of the event is created automatically. After an event is dispatched, its target property cannot be changed, so you must create a new copy of the event for redispatching to work.

Returns
Boolean — Returns true if the event was successfully dispatched. A value of false indicates failure or that preventDefault() was called on the event.

See also

getComplexProperty

()method 
object_proxy function getComplexProperty(name:*, value:*):*

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Provides a place for subclasses to override how a complex property that needs to be either proxied or daisy chained for event bubbling is managed.

Parameters

name:* — Typically a string containing the name of the property, or possibly a QName where the property name is found by inspecting the localName property.
 
value:* — The property value.

Returns
* — The property value or an instance of ObjectProxy.

getProperty

()method 
override flash_proxy function getProperty(name:*):*

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Returns the specified property value of the proxied object.

Parameters

name:* — Typically a string containing the name of the property, or possibly a QName where the property name is found by inspecting the localName property.

Returns
* — The value of the property. In some instances this value may be an instance of ObjectProxy.

hasEventListener

()method 
public function hasEventListener(type:String):Boolean

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Checks whether there are any event listeners registered for a specific type of event. This allows you to determine where an object has altered handling of an event type in the event flow hierarchy. For more information, see the flash.events.EventDispatcher class.

Parameters

type:String — The type of event

Returns
Boolean — Returns true if a listener of the specified type is registered; false otherwise.

See also

propertyChangeHandler

()method 
public function propertyChangeHandler(event:PropertyChangeEvent):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Called when a complex property is updated.

Parameters

event:PropertyChangeEvent — An event object that has changed.

readExternal

()method 
public function readExternal(input:IDataInput):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Since Flex only uses ObjectProxy to wrap anonymous objects, the server flex.messaging.io.ObjectProxy instance serializes itself as a Map that will be returned as a plain ActionScript object. You can then set the object_proxy object property to this value.

Parameters

input:IDataInput — The source object from which the ObjectProxy is deserialized.

removeEventListener

()method 
public function removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Removes an event listener. If there is no matching listener registered with the EventDispatcher object, a call to this method has no effect. For more information, see the flash.events.EventDispatcher class.

Parameters

type:String — The type of event.
 
listener:Function — The listener object to remove.
 
useCapture:Boolean (default = false) — Specifies whether the listener was registered for the capture phase or the target and bubbling phases. If the listener was registered for both the capture phase and the target and bubbling phases, two calls to removeEventListener() are required to remove both, one call with useCapture set to true, and another call with useCapture set to false.

See also

setProperty

()method 
override flash_proxy function setProperty(name:*, value:*):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Updates the specified property on the proxied object and sends notification of the update to the handler.

Parameters

name:* — Object containing the name of the property that should be updated on the proxied object.
 
value:* — Value that should be set on the proxied object.

setupPropertyList

()method 
protected function setupPropertyList():void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

This method creates an array of all of the property names for the proxied object. Descendants must override this method if they wish to add more properties to this list. Be sure to call super.setupPropertyList before making any changes to the propertyList property.

willTrigger

()method 
public function willTrigger(type:String):Boolean

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Checks whether an event listener is registered with this object or any of its ancestors for the specified event type. This method returns true if an event listener is triggered during any phase of the event flow when an event of the specified type is dispatched to this object or any of its descendants. For more information, see the flash.events.EventDispatcher class.

Parameters

type:String — The type of event.

Returns
Boolean — Returns true if a listener of the specified type will be triggered; false otherwise.

See also

writeExternal

()method 
public function writeExternal(output:IDataOutput):void

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Since Flex only serializes the inner ActionScript object that it wraps, the server flex.messaging.io.ObjectProxy populates itself with this anonymous object's contents and appears to the user as a Map.

Parameters

output:IDataOutput — The source object from which the ObjectProxy is deserialized.