Single Listener for multiple controls

Question

Assuming I have 3 Slider Controls representing 3 different properties of an Object. How could I use a Single Listener/Handler to track the changes from all 3 sliders.

Answer 1

Simply attach the same ChangeListener to all three sliders, but instead of looking at the new/old value parameters, just query all 3 of the sliders for their current values and use those.
package hs.javafx;
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Scene;
import javafx.scene.control.Slider;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class ThreeSliderTest extends Application {
  public static void main(String[] args) {
    Application.launch(args);
  @Override
  public void start(Stage primaryStage) throws Exception {
    VBox vbox = new VBox();
    final Slider slider = new Slider(0, 100, 15);
    final Slider slider2 = new Slider(0, 100, 65);
    final Slider slider3 = new Slider(0, 100, 55);
    ChangeListener<Number> changeListener = new ChangeListener<Number>() {
      @Override
      public void changed(ObservableValue<? extends Number> observable, Number oldValue, Number value) {
        System.out.println("R,G,B = " + slider.getValue() + "," + slider2.getValue() + "," + slider3.getValue());
    slider.valueProperty().addListener(changeListener);
    slider2.valueProperty().addListener(changeListener);
    slider3.valueProperty().addListener(changeListener);
    vbox.getChildren().addAll(slider, slider2, slider3);
    Scene scene = new Scene(vbox);
    primaryStage.setScene(scene);
    primaryStage.show();
}