override public function addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void| Versione linguaggio: | ActionScript 3.0 |
| Versione prodotto: | Adobe Digital Enterprise Platform Experience Services - Composite Application Framework 10 |
| Versioni runtime: | AIR 2.6, Flash Player 10.2 |
Overridden EventDispatcher addEventListener.
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).
Parametri
| type:String — The type of event.
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| 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:
The function can have any name.
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| useCapture:Boolean (default = false)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.
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| priority:int (default = 0) |
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| useWeakReference:Boolean (default = false)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.
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FrameworkInitializer