包 | com.adobe.icomm.assetplacement.model |
类 | public final class PackageDefinitionLoader |
继承 | PackageDefinitionLoader Object |
语言版本: | ActionScript 3.0 |
产品版本: | Asset Placement Building Block 9.5 |
运行时版本: | AIR 1.0, Flash Player 9, Flash Player 10 |
The PackageDefinition
object loads the package definition file (package.xml) in a
non-blocking operation. The PackageDefinitionLoader uses an eventListener/eventDispatcher mechanism
to get a reference to the PackageDefinition object, in order to ensure:
- That every caller gets access to the same object (to prevent redundant loading of the package.xml file); and
- That the package is fully loaded before a caller makes use of it.
In order to get a reference to the PackageDefinition object, add an event listener for the
PackageDefinitionReadyEvent and make a call to getPackageDefinition()
. When
the PackageDefinition object is ready for use, the listener will be called. Add an event listener for the
PackageDefinitionLoadFailed event to get notification that the package definition failed to load.
Note: the PackageDefinitionReadyEvent listener should be removed once the event fires; if it is not removed the event may fire multiple times when other requesters ask for the PackageDefinition object.
相关 API 元素
com.adobe.icomm.assetplacement.model.PackageDefinitionReadyEvent
com.adobe.icomm.assetplacement.model.PackageDefinitionLoadFailedEvent
方法 | 由以下参数定义 | ||
---|---|---|---|
Calling the constructor will result in a runtime error. | PackageDefinitionLoader | ||
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void [静态]
Registers an event listener object with an EventDispatcher object so that the listener receives notification
of an event. | PackageDefinitionLoader | ||
表示对象是否已经定义了指定的属性。 | Object | ||
表示 Object 类的实例是否在指定为参数的对象的原型链中。 | Object | ||
表示指定的属性是否存在、是否可枚举。 | Object | ||
[静态]
Ask for the PackageDefinition object. | PackageDefinitionLoader | ||
[静态]
Removes a listener from the EventDispatcher object. | PackageDefinitionLoader | ||
设置循环操作动态属性的可用性。 | Object | ||
返回此对象的字符串表示形式,其格式设置遵守区域设置特定的约定。 | Object | ||
返回指定对象的字符串表示形式。 | Object | ||
返回指定对象的原始值。 | Object |
PackageDefinitionLoader | () | 构造函数 |
public function PackageDefinitionLoader()
语言版本: | ActionScript 3.0 |
产品版本: | Asset Placement Building Block 9.5 |
运行时版本: | AIR 1.0, Flash Player 9, Flash Player 10 |
Calling the constructor will result in a runtime error.
addEventListener | () | 方法 |
public static function addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
语言版本: | ActionScript 3.0 |
产品版本: | Asset Placement Building Block 9.5 |
运行时版本: | AIR 1.0, Flash Player 9, Flash Player 10 |
Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event. You can register event listeners on all nodes in the display list for a specific type of event, phase, and priority.
After you successfully register an event listener, you cannot change its priority through additional calls to addEventListener(). To change a listener's priority, you must first call removeListener(). Then you can register the listener again with the new priority level.
Keep in mind that after the listener is registered, subsequent calls to addEventListener() with a different type or useCapture value result in the creation of a separate listener registration. For example, if you first register a listener with useCapture set to true, it listens only during the capture phase. If you call addEventListener() again using the same listener object, but with useCapture set to false, you have two separate listeners: one that listens during the capture phase and another that listens during the target and bubbling phases.
You cannot register an event listener for only the target phase or the bubbling phase. Those phases are coupled during registration because bubbling applies only to the ancestors of the target node.
If you no longer need an event listener, remove it by calling removeEventListener(), or memory problems could result. Event listeners are not automatically removed from memory because the garbage collector does not remove the listener as long as the dispatching object exists (unless the useWeakReference parameter is set to true).
Copying an EventDispatcher instance does not copy the event listeners attached to it. (If your newly created node needs an event listener, you must attach the listener after creating the node.) However, if you move an EventDispatcher instance, the event listeners attached to it move along with it.
If the event listener is being registered on a node while an event is being processed on this node, the event listener is not triggered during the current phase but can be triggered during a later phase in the event flow, such as the bubbling phase.
If an event listener is removed from a node while an event is being processed on the node, it is still triggered by the current actions. After it is removed, the event listener is never invoked again (unless registered again for future processing).
参数
type:String — The type of event.
| |
listener:Function — The listener function that processes the event. This function must accept an Event object as
its only parameter and must return nothing, as this example shows:
function(evt:Event):void The function can have any name. | |
useCapture:Boolean (default = false ) — Determines whether the listener works in the capture phase or the target and bubbling phases.
If useCapture is set to true, the listener processes the event only during the capture phase and not in the target
or bubbling phase. If useCapture is false, the listener processes the event only during the target or bubbling
phase. To listen for the event in all three phases, call addEventListener twice, once with useCapture set to true,
then again with useCapture set to false.
| |
priority:int (default = 0 ) — The priority level of the event listener. The priority is designated by a signed 32-bit integer.
The higher the number, the higher the priority. All listeners with priority n are processed before listeners of
priority n-1. If two or more listeners share the same priority, they are processed in the order in which they
were added. The default priority is 0.
| |
useWeakReference:Boolean (default = false ) — Determines whether the reference to the listener is strong or weak. A strong reference
(the default) prevents your listener from being garbage-collected. A weak reference does not.
Class-level member functions are not subject to garbage collection, so you can set useWeakReference to true for class-level member functions without subjecting them to garbage collection. If you set useWeakReference to true for a listener that is a nested inner function, the function will be garbage-collected and no longer persistent. If you create references to the inner function (save it in another variable) then it is not garbage-collected and stays persistent. |
readyPackageDefinition | () | 方法 |
public static function readyPackageDefinition(onPackageDefinitionReady:Function = null):void
语言版本: | ActionScript 3.0 |
产品版本: | Asset Placement Building Block 9.5 |
运行时版本: | AIR 1.0, Flash Player 9, Flash Player 10 |
Ask for the PackageDefinition object. When the object is ready, listeners will receive a PackageDefinitionReadyEvent that contains a reference to the PackageDefinition object.
参数
onPackageDefinitionReady:Function (default = null ) — The function to be called when the PackageDefinitionReadyEvent fires.
|
相关 API 元素
removeEventListener | () | 方法 |
public static function removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
语言版本: | ActionScript 3.0 |
产品版本: | Asset Placement Building Block 9.5 |
运行时版本: | AIR 1.0, Flash Player 9, Flash Player 10 |
Removes a listener from the EventDispatcher object. If there is no matching listener registered with the EventDispatcher object, a call to this method has no effect.
参数
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.
|
public function init():void { PackageDefinitionLoader.addEventListener(PackageDefinitionReadyEvent.PACKAGE_DEFINITION_READY, onPackageDefinitionReady); PackageDefinitionLoader.addEventListener(PackageDefinitionLoadFailedEvent.PACKAGE_DEFINITION_LOAD_FAILED, onPackageDefinitionLoadFailed); PackageDefinitionLoader.readyPackageDefinition(); } public function onPackageDefinitionReady(event:PackageDefinitionReadyEvent):void { // Once we get the ready event, we don't want to listen for it anymore PackageDefinitionLoader.removeEventListener(PackageDefinitionReadyEvent.PACKAGE_DEFINITION_READY, onPackageDefinitionReady); PackageDefinitionLoader.removeEventListener(PackageDefinitionLoadFailedEvent.PACKAGE_DEFINITION_LOAD_FAILED, onPackageDefinitionLoadFailed); var packageDef:PackageDefinition = event.packageDefinition; } public function onPackageDefinitionLoadFailed(event:PackageDefinitionLoadFailedEvent):void { PackageDefinitionLoader.removeEventListener(PackageDefinitionReadyEvent.PACKAGE_DEFINITION_READY, onPackageDefinitionReady); PackageDefinitionLoader.removeEventListener(PackageDefinitionLoadFailedEvent.PACKAGE_DEFINITION_LOAD_FAILED, onPackageDefinitionLoadFailed); var error:String = event.error; }
Tue Jun 12 2018, 11:04 AM Z