WeakInvalidationListener (JavaFX 17)

Module javafx.base
Package javafx.beans

## Class WeakInvalidationListener

- java.lang.Object
- - javafx.beans.WeakInvalidationListener

- All Implemented Interfaces:
    `InvalidationListener`, `WeakListener`

      public final class WeakInvalidationListener
      extends Object
      implements InvalidationListener, WeakListener

  A `WeakInvalidationListener` can be used if an `Observable` 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.

  A `WeakInvalidationListener` is created by passing in the original `InvalidationListener`. The `WeakInvalidationListener` should then be registered to listen for changes of the observed object.

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

  Since:
    JavaFX 2.0
  See Also:
    `InvalidationListener`, `Observable`

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `WeakInvalidationListener​(InvalidationListener listener)` | The constructor of `WeakInvalidationListener`.

  - ### Method Summary

    - ### Methods declared in class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

    - ### Methods declared in interface javafx.beans.InvalidationListener

      `invalidated`

    - ### Methods declared in interface javafx.beans.WeakListener

      `wasGarbageCollected`

- - ### Constructor Detail

    - #### WeakInvalidationListener

          public WeakInvalidationListener​(InvalidationListener listener)

      The constructor of `WeakInvalidationListener`.
      Parameters:
        `listener` - The original listener that should be notified