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sliderjavafxlabeldrag

Make a label update while dragging a slider


I'm using a Slider in my javaFX project and I have a Label that updates when I move the slider.

I want the Label to update whilst I'm dragging the Slider and not only when the drag is dropped.

This is my code:

 betSlider.valueChangingProperty().addListener(new ChangeListener<Boolean>() {
            @Override
            public void changed(ObservableValue<? extends Boolean> source, Boolean oldValue, Boolean newValue) {
                betLabel.textProperty().setValue(String.valueOf((int)betSlider.getValue()));
  } });

Solution

  • You just need to change the valueChangingProperty() to valueProperty() and TADA, it works as you want !

    A small sample is attached here :

    import javafx.application.Application;
    import javafx.beans.value.ChangeListener;
    import javafx.beans.value.ObservableValue;
    import javafx.scene.Scene;
    import javafx.scene.control.Label;
    import javafx.scene.control.Slider;
    import javafx.scene.layout.VBox;
    import javafx.stage.Stage;
    
    public class Demo extends Application {
    
        @Override
        public void start(Stage primaryStage) {
            // Add a scene
            VBox root = new VBox();
            Scene scene = new Scene(root, 500, 200);
    
            final Label betLabel = new Label("sdsd");
    
            final Slider betSlider = new Slider();
            betSlider.valueProperty().addListener(new ChangeListener<Number>() {
    
                    @Override
                    public void changed(
                       ObservableValue<? extends Number> observableValue, 
                       Number oldValue, 
                       Number newValue) { 
                          betLabel.textProperty().setValue(
                               String.valueOf(newValue.intValue());
                      }
                }
            });
    
            root.getChildren().addAll(betSlider, betLabel);
            betLabel.textProperty().setValue("abc");
    
            // show the stage
            primaryStage.setTitle("Demo");
            primaryStage.setScene(scene);
            primaryStage.show();
        }
    
        public static void main(String[] args) {
            launch(args);
        }
    }