JavaFX Tutorial - JavaFX ProgressIndicator








A progress indicator shows the progress of an operations in JavaFX in the form of a dynamically changing pie chart.

The following code shows how to create ProgressIndicator with an indeterminate value. 

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.ProgressIndicator;
import javafx.stage.Stage;
/*from  w  w  w. j a va 2  s.  c  om*/
public class Main extends Application {

  @Override
  public void start(Stage stage) {
    Group root = new Group();
    Scene scene = new Scene(root, 260, 80);
    stage.setScene(scene);

    Group g = new Group();

    ProgressIndicator p1 = new ProgressIndicator();
   
    
    g.getChildren().add(p1);
    
    scene.setRoot(g);
    stage.show();
  }

  public static void main(String[] args) {
    launch(args);
  }
}

The code above generates the following result.

null




Creating ProgressIndicator

The following code creates a ProgressIndicator by passing in the progress value.

ProgressIndicator pi = new ProgressIndicator(0.6);

We can create the progress indicator without parameters by using an empty constructor. And then we can assign the value by using the setProgress method.

If the progress cannot be determined, we can set progress controls in indeterminate mode until the length of the task is determined.

The following code shows how to create a ProgressIndicator which is 25% complete. 

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.ProgressIndicator;
import javafx.stage.Stage;
/*from   w w  w.  j  av  a2 s  .c o  m*/
public class Main extends Application {

  @Override
  public void start(Stage stage) {
    Group root = new Group();
    Scene scene = new Scene(root, 260, 80);
    stage.setScene(scene);

    Group g = new Group();

    ProgressIndicator p1 = new ProgressIndicator();
    p1.setProgress(0.25F);
    
    g.getChildren().add(p1);
    
    scene.setRoot(g);
    stage.show();
  }

  public static void main(String[] args) {
    launch(args);
  }
}

The code above generates the following result.

null




ProgressIndicator and Background Processes

/*w  w  w . j  a v  a 2s  .  c  o m*/
import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.concurrent.Task;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.ProgressIndicator;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

public class Main extends Application {
    Task copyWorker;
    public static void main(String[] args) {
        Application.launch(args);
    }
    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("Background Processes");
        Group root = new Group();
        Scene scene = new Scene(root, 330, 120, Color.WHITE);

        BorderPane mainPane = new BorderPane();
        root.getChildren().add(mainPane);

        final Label label = new Label("Files Transfer:");
        final ProgressIndicator progressIndicator = new ProgressIndicator(0);

        final HBox hb = new HBox();
        hb.setSpacing(5);
        hb.setAlignment(Pos.CENTER);
        hb.getChildren().addAll(label, progressIndicator);
        mainPane.setTop(hb);

        final Button startButton = new Button("Start");
        final Button cancelButton = new Button("Cancel");
        final HBox hb2 = new HBox();
        hb2.setSpacing(5);
        hb2.setAlignment(Pos.CENTER);
        hb2.getChildren().addAll(startButton, cancelButton);
        mainPane.setBottom(hb2);

        startButton.setOnAction(new EventHandler<ActionEvent>() {

            public void handle(ActionEvent event) {
                startButton.setDisable(true);
                progressIndicator.setProgress(0);
                cancelButton.setDisable(false);
                copyWorker = createWorker();

                progressIndicator.progressProperty().unbind();
                progressIndicator.progressProperty().bind(copyWorker.progressProperty());
               
                copyWorker.messageProperty().addListener(new ChangeListener<String>() {
                    public void changed(ObservableValue<? extends String> observable, String oldValue, String newValue) {
                        System.out.println(newValue);
                    }
                });

                new Thread(copyWorker).start();
            }
        });
        cancelButton.setOnAction(new EventHandler<ActionEvent>() {
            public void handle(ActionEvent event) {
                startButton.setDisable(false);
                cancelButton.setDisable(true);
                copyWorker.cancel(true);
                progressIndicator.progressProperty().unbind();
                progressIndicator.setProgress(0);
                System.out.println("cancelled.");
            }
        });
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public Task createWorker() {
        return new Task() {
            @Override
            protected Object call() throws Exception {
                for (int i = 0; i < 10; i++) {
                    Thread.sleep(2000);
                    updateMessage("2000 milliseconds");
                    updateProgress(i + 1, 10);
                }
                return true;
            }
        };
    }
}

The code above generates the following result.

null