ActionScript® 3.0 Reference for the Adobe® Flash® Platform
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org.osmf.elements 

ProxyElement  - AS3 OSMF

Packageorg.osmf.elements
Classpublic class ProxyElement
InheritanceProxyElement Inheritance MediaElement Inheritance EventDispatcher Inheritance Object
Subclasses DurationElement, LoadFromDocumentElement

Language Version: ActionScript 3.0
Product Version: OSMF 1.0
Runtime Versions: Flash Player 10, AIR 1.5

ProxyElement is a media element that acts as a wrapper for another MediaElement. Its purpose is to control access to the wrapped element.

ProxyElement is not instantiated directly but rather used as the base class for creating wrappers for specific purposes. ProxyElement can be subclassed for any trait type or set of trait types. The subclass controls access to the proxied element either by overriding one or more of the proxied element's traits or by blocking them.

To override any of the proxied element's traits, the subclass creates its own trait instances, which it substitutes for the proxied element's traits that it wishes to override.

To block traits, the subclass prevents the traits of the proxied element from being exposed by setting the ProxyElement's blockedTraits property for the trait types that it wants to block. This causes the proxied element's hasTrait() method to return false and its getTrait() method to return null for the blocked trait types.

A ProxyElement normally dispatches the proxied element's events, unless the trait's type is among those that are blocked by the ProxyElement.

ProxyElement subclasses are useful for modifying the behavior of a MediaElement in a non-invasive way. An example would be adding temporal capabilities to a set of ImageElements to present them in a slide show in which the images are displayed for a specified duration. The ProxyElement subclass would proxy the non-temporal ImageElements and override the proxied element's TimeTrait to return a custom instance of that trait. A similar approach can be applied to other traits, either to provide an alternate implementation of some of the proxied element's underlying traits, to provide an implementation when a needed underlying trait does not exist, or to prevent an underlying trait from being exposed at all.

Related API Elements



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 Inheritedcontainer : IMediaContainer
[read-only] The media container that this element uses.
MediaElement
 InheritedmetadataNamespaceURLs : Vector.<String>
[read-only] A Vector containing the namespace URLs for all Metadata objects stored within this MediaElement.
MediaElement
  proxiedElement : MediaElement
The MediaElement for which this ProxyElement serves as a proxy, or wrapper.
ProxyElement
 Inheritedresource : MediaResourceBase
The media resource that this media element operates on.
MediaElement
 InheritedtraitTypes : Vector.<String>
[read-only] A Vector of MediaTraitType values representing the trait types on this media element.
MediaElement
Protected Properties
 PropertyDefined By
  blockedTraits : Vector.<String>
The set of MediaTraitTypes that this ProxyElement will block.
ProxyElement
Public Methods
 MethodDefined By
  
ProxyElement(proxiedElement:MediaElement = null)
Constructor.
ProxyElement
 Inherited
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
 Inherited
addMetadata(namespaceURL:String, metadata:Metadata):void
Adds a Metadata object to this MediaElement under the specified namespace URL.
MediaElement
 Inherited
Dispatches an event into the event flow.
EventDispatcher
 Inherited
Returns the Metadata object that is stored under this MediaElement with the specified namespace URL.
MediaElement
 Inherited
Returns the media trait of the specified type.
MediaElement
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Determines whether this media element has a media trait of the specified type.
MediaElement
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
 Inherited
Removes the Metadata object that was stored under this MediaElement with the specified namespace URL.
MediaElement
 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
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Protected Methods
 MethodDefined By
 Inherited
Adds a new media trait to this media element.
MediaElement
 Inherited
Removes a media trait from this media element.
MediaElement
 Inherited
Sets up the traits for this media element.
MediaElement
Events
 Event Summary Defined By
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.EventDispatcher
 InheritedDispatched when the element's container property changed.MediaElement
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.EventDispatcher
 InheritedDispatched when an error which impacts the operation of the media element occurs.MediaElement
 InheritedDispatched when a info which impacts the operation of the media element is available.MediaElement
 InheritedDispatched when a Metadata object has been added to this media element.MediaElement
 InheritedDispatched when a Metadata object has been removed from this media element.MediaElement
 InheritedDispatched when a trait is added to the media element.MediaElement
 InheritedDispatched when a trait is removed from the media element.MediaElement
Property Detail

blockedTraits

property
blockedTraits:Vector.<String>

Language Version: ActionScript 3.0
Product Version: OSMF 1.0
Runtime Versions: Flash Player 10, AIR 1.5

The set of MediaTraitTypes that this ProxyElement will block. When a trait is blocked, the ProxyElement will prevent that trait from being exposed when the proxied element contains the trait and the proxy does not. Subclasses can call this to selectively block access to the traits of the proxied element on a per-type basis.



Implementation
    protected function get blockedTraits():Vector.<String>
    protected function set blockedTraits(value:Vector.<String>):void

proxiedElement

property 
proxiedElement:MediaElement

Language Version: ActionScript 3.0
Product Version: OSMF 1.0
Runtime Versions: Flash Player 10, AIR 1.5

The MediaElement for which this ProxyElement serves as a proxy, or wrapper.



Implementation
    public function get proxiedElement():MediaElement
    public function set proxiedElement(value:MediaElement):void
Constructor Detail

ProxyElement

()Constructor
public function ProxyElement(proxiedElement:MediaElement = null)

Language Version: ActionScript 3.0
Product Version: OSMF 1.0
Runtime Versions: Flash Player 10, AIR 1.5

Constructor.

Parameters
proxiedElement:MediaElement (default = null) — MediaElement to proxy. Changes to the proxied element are reflected in the proxy element's properties and events, with the exception of those changes for which an override takes precedence. If the param is null, then it must be set (via the proxiedElement setter) immediately after this constructor call, and before any other methods on this ProxyElement are called, or an IllegalOperationError will be thrown.