Locking the GUI, spinning dial (simillar to JXLayer)

Question

Hello,
I am looking for a way to lock the GUI (and display a spinning dial) when a long running thread is running.
How would one do this with JavaFX?
Thanks in advance

Answer 1

Yes. Using a progress indicator instead of a cursor is a good idea.
   import javafx.application.Application;
import javafx.beans.binding.When;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.concurrent.Task;
import javafx.concurrent.Worker.State;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
import javafx.scene.Cursor;
import javafx.scene.control.ProgressIndicator;
public class TaskProgs extends Application {
    @Override
    public void start(Stage primaryStage) {
        Button btn = new Button();
        btn.setText("Submit");
        btn.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent event) {
                System.out.println("click...");
        final StackPane root = new StackPane();
        root.getChildren().add(btn);
        final Scene scene = new Scene(root, 300, 250);
        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
        Task<Integer> task = new Task<Integer>() {
            @Override
            protected Integer call() throws Exception {
                int iterations;
                for (iterations = 0; iterations < 10000000; iterations++) {
                    if (isCancelled()) {
                        updateMessage("Cancelled");
                        break;
                    updateMessage("Iteration " + iterations);
                    updateProgress(iterations, 10000000);
                return iterations;
        final ProgressIndicator pi = new ProgressIndicator();
        pi.setProgress(ProgressIndicator.INDETERMINATE_PROGRESS); 
        scene.getRoot().mouseTransparentProperty().bind(task.runningProperty());
        Thread th = new Thread(task);
        th.start();
        task.stateProperty().addListener(new ChangeListener<State>() {
            public void changed(ObservableValue<? extends State> observable, State oldValue, State newValue) {
                if (newValue == State.SUCCEEDED) {
                    root.getChildren().remove(pi);
                } else if (newValue == State.RUNNING) {
                    root.getChildren().add(pi);
    public static void main(String[] args) {
        launch(args);