griffon.transform

Annotation Type ChangeListener

@Retention(value=SOURCE)
 @Target(value=FIELD)
public @interface ChangeListener

Annotates a property.

This transformation provides a convenient way to register ChangeListeners on an observable bean by leveraging Groovy's closures and the Groovy cast operator.

The following code exemplifies what must be written by hand in order to register a ChangeListener.

 import griffon.transform.FXObservable
 import javafx.beans.value.ChangeListener

 class MyModel {
     @FXObservable String name
     @FXObservable String lastname

     private def snoopAll = { ob, ov, nv -> ... }

     MyModel() {
         nameProperty().addListener(snoopAll as ChangeListener)
         lastnameProperty().addListener({ ob, ov, nv ->
             controller.someAction(nv)
         } as ChangeListener)
     }
 }
 

Applying @ChangeListener to the previous snippet results in the following code

 import griffon.transform.FXObservable
 import griffon.transform.ChangeListener

 class MyModel {
     @FXObservable
     @ChangeListener(snoopAll)
     String name

     @FXObservable
     @ChangeListener({ ob, ov, nv -> controller.someAction(nv)})
     String lastname

     private def snoopAll = { ob, ov, nv -> ... }
 }
 

Any closures found as the annotation's value will be either transformed into inner classes that implement ChangeListener (when the value is a closure defined in place) or be casted as a proxy of ChangeListener (when the value is a property reference found in the same class).

List of closures are also supported.

Author:

Andres Almiray

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
String	value

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	weak If the ChangeListener should be wrapped with a WeakChangeListener or not

Element Detail

value

public abstract String value

weak

public abstract boolean weak

If the ChangeListener should be wrapped with a WeakChangeListener or not

Since:

2.4.0

Default:

true