javafx.event

Class WeakEventHandler<T extends Event>

java.lang.Object

javafx.event.WeakEventHandler<T>

Type Parameters:

T - the event class this handler can handle

All Implemented Interfaces:

public final class WeakEventHandler<T extends Event>
extends Object
implements EventHandler<T>

Used in event handler registration in place of its associated event handler. Its sole purpose is to break the otherwise strong reference between an event handler container and its associated event handler. While the container still holds strong reference to the registered WeakEventHandler proxy, the proxy itself references the original handler only weakly and so doesn't prevent it from being garbage collected. Until this weak reference is broken, any event notification received by the proxy is forwarded to the original handler.

Since:

JavaFX 8.0

Constructor Summary

Constructors
Constructor and Description

WeakEventHandler(EventHandler<T> eventHandler)
Creates a new instance of WeakEventHandler.

Constructors
Constructor and Description
`WeakEventHandler(EventHandler<T> eventHandler)` Creates a new instance of `WeakEventHandler`.

Method Summary

All MethodsInstance MethodsConcrete Methods
Modifier and Type	Method and Description
`void`	`handle(T event)` Forwards event notification to the associated event handler.
`boolean`	`wasGarbageCollected()` Indicates whether the associated event handler has been garbage collected.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- WeakEventHandler
```
public WeakEventHandler(EventHandler<T> eventHandler)
```
  Creates a new instance of WeakEventHandler.
  
  Parameters:
  
  eventHandler - the original event handler to which to forward event notifications

Method Detail
- wasGarbageCollected
```
public boolean wasGarbageCollected()
```
  Indicates whether the associated event handler has been garbage collected. Used by containers to detect when the storage of corresponding references to this WeakEventHandler is no longer necessary.
  
  Returns:
  
  true if the associated handler has been garbage collected, false otherwise
- handle
```
public void handle(T event)
```
  Forwards event notification to the associated event handler.
  
  Specified by:
  
  handle in interface EventHandler<T extends Event>
  
  Parameters:
  
  event - the event which occurred

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Documentation extracted from JavaFX API Documentation.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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Class WeakEventHandler<T extends Event>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WeakEventHandler

Method Detail

wasGarbageCollected

handle