Tuesday, February 25, 2014

Update JavaFX UI in scheduled task, of Thread(Task), Thread(Runnable) and Timer with TimerTask

This example implement scheduled task, of Thread(Task), Thread(Runnable) and Timer with TimerTask. To update JavaFX UI ProgressBar.



package javafx_timertask;

import java.util.Timer;
import java.util.TimerTask;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.concurrent.Task;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.ProgressBar;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

/**
 *
 * @web http://java-buddy.blogspot.com/
 */
public class JavaFX_TimerTask extends Application {
    
    final int MAX = 100;
    
    Thread myTaskThread;
    Thread myRunnableThread;
    Timer myTimer;
    
    MyTask myTask;
    MyRunnable myRunnable;
    MyTimerTask myTimerTask;
    
    @Override
    public void start(Stage primaryStage) {
        
        myTask = new MyTask();
        ProgressBar progressBarTask = new ProgressBar();
        progressBarTask.setProgress(0);
        progressBarTask.progressProperty().bind(myTask.progressProperty());
        
        ProgressBar progressBarRunnable = new ProgressBar();
        progressBarRunnable.setProgress(0);
        myRunnable = new MyRunnable(progressBarRunnable);
        
        ProgressBar progressBarTimerTask = new ProgressBar();
        progressBarTimerTask.setProgress(0);
        myTimerTask = new MyTimerTask(progressBarTimerTask);
        
        Button btnStart = new Button("Start Task");
        btnStart.setOnAction(new EventHandler<ActionEvent>() {
 
            @Override
            public void handle(ActionEvent t) {
                myTaskThread = new Thread(myTask);
                myTaskThread.start();
                
                myRunnableThread = new Thread(myRunnable);
                myRunnableThread.start();
                
                myTimer = new Timer();
                myTimer.scheduleAtFixedRate(myTimerTask, 0, 100);
            }
        });
        
        VBox vBox = new VBox();
        vBox.setPadding(new Insets(5, 5, 5, 5));
        vBox.setSpacing(5);
        vBox.getChildren().addAll(
                new Label("Run in Thread(Task)"),
                progressBarTask,
                new Label("Run in Thread(Runnable)"),
                progressBarRunnable,
                new Label("Run in Timer and TimerTask"),
                progressBarTimerTask,
                btnStart);
        
        StackPane root = new StackPane();
        root.getChildren().add(vBox);
 
        Scene scene = new Scene(root, 300, 250);
 
        primaryStage.setTitle("java-buddy.blogspot.com");
        primaryStage.setScene(scene);
        primaryStage.show();

    }

    public static void main(String[] args) {
        launch(args);
    }
    
    class MyTask extends Task<Void>{
        
        @Override
        protected Void call() throws Exception {
            for (int i = 1; i <= MAX; i++) {
                updateProgress(i, MAX);
                Thread.sleep(100);
            }
            return null;
        }
        
    }
    
    class MyRunnable implements Runnable{
        
        ProgressBar bar;

        public MyRunnable(ProgressBar b) {
            bar = b;
        }

        @Override
        public void run() {
            for (int i = 1; i <= MAX; i++) {
                
                final double update_i = i;
                
                //Not work if update JavaFX UI here!
                //bar.setProgress(i/MAX);
                
                //Update JavaFX UI with runLater() in UI thread
                Platform.runLater(new Runnable(){

                    @Override
                    public void run() {
                        bar.setProgress(update_i/MAX);
                    }
                });
                
                try {
                    Thread.sleep(100);
                } catch (InterruptedException ex) {
                    Logger.getLogger(JavaFX_TimerTask.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }
        
    }
    
    class MyTimerTask extends TimerTask{

        ProgressBar bar;
        double count;

        public MyTimerTask(ProgressBar b) {
            bar = b;
            count = 0;
        }

        @Override
        public void run() {

            bar.setProgress(count++/MAX);
            
            if(count >= MAX){
                myTimer.cancel();
            }
            
        }
        
    }
    
}


2 comments:

  1. HI, this helped a lot, thanks for sharing!

    ReplyDelete
  2. Is not neccessary to update JavaFX UI with runLater in MyTimerTask.run() as in MyRunnable.run() ?

    ReplyDelete