Interface ChangeListener<T>

All Known Implementing Classes:
BidirectionalBinding, BidirectionalBinding.StringConversionBidirectionalBinding, WeakChangeListener
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface public interface ChangeListener<T>
A ChangeListener is notified whenever the value of an ObservableValue changes. It can be registered and unregistered with ObservableValue.addListener(ChangeListener) respectively ObservableValue.removeListener(ChangeListener)

For an in-depth explanation of change events and how they differ from invalidation events, see the documentation of ObservableValue.

The same instance of ChangeListener can be registered to listen to multiple ObservableValues.

Since:
JavaFX 2.0
See Also:
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    changed(ObservableValue<? extends T> observable, T oldValue, T newValue)
    This method needs to be provided by an implementation of ChangeListener.
  • Method Details

    • changed

      void changed(ObservableValue<? extends T> observable, T oldValue, T newValue)
      This method needs to be provided by an implementation of ChangeListener. It is called if the value of an ObservableValue changes.

      In general is is considered bad practice to modify the observed value in this method.

      Parameters:
      observable - The ObservableValue which value changed
      oldValue - The old value
      newValue - The new value