javafx.collections

Class WeakListChangeListener<E>

java.lang.Object

javafx.collections.WeakListChangeListener<E>

Type Parameters:

E - The type of the observed value

All Implemented Interfaces:

public final class WeakListChangeListener<E>
extends Object
implements ListChangeListener<E>, WeakListener

A WeakListChangeListener can be used, if an ObservableList should only maintain a weak reference to the listener. This helps to avoid memory leaks, that can occur if observers are not unregistered from observed objects after use.

WeakListChangeListener are created by passing in the original ListChangeListener. The WeakListChangeListener should then be registered to listen for changes of the observed object.

Note: You have to keep a reference to the ListChangeListener, that was passed in as long as it is in use, otherwise it will be garbage collected to soon.

Since:

JavaFX 2.1

Constructors
Constructor and Description
`WeakListChangeListener(ListChangeListener<E> listener)` The constructor of `WeakListChangeListener`.

Method Summary

All MethodsInstance MethodsConcrete Methods
Modifier and Type	Method and Description
`void`	`onChanged(ListChangeListener.Change<? extends E> change)` Called after a change has been made to an ObservableList.
`boolean`	`wasGarbageCollected()` Returns `true` if the linked listener was garbage-collected.

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

Constructor Detail
- WeakListChangeListener
```
public WeakListChangeListener(ListChangeListener<E> listener)
```
  The constructor of WeakListChangeListener.
  
  Parameters:
  
  listener - The original listener that should be notified

Method Detail
- wasGarbageCollected
```
public boolean wasGarbageCollected()
```
  Returns true if the linked listener was garbage-collected. In this case, the listener can be removed from the observable.
  
  Specified by:
  
  wasGarbageCollected in interface WeakListener
  
  Returns:
  
  true if the linked listener was garbage-collected.
- onChanged
```
public void onChanged(ListChangeListener.Change<? extends E> change)
```
  Called after a change has been made to an ObservableList.
  
  Specified by:
  
  onChanged in interface ListChangeListener<E>
  
  Parameters:
  
  change - an object representing the change that was done
  
  See Also:
  
  ListChangeListener.Change

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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 WeakListChangeListener<E>

Nested Class Summary

Nested classes/interfaces inherited from interface javafx.collections.ListChangeListener

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WeakListChangeListener

Method Detail

wasGarbageCollected

onChanged