javafx - Line Chart Live update

Question

Live update Line Chart

I want to modify this simple example of Line Chart and add live update.

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.stage.Stage;


public class LineChartSample extends Application {

    @Override public void start(Stage stage) {
        stage.setTitle("Line Chart Sample");
        //defining the axes
        final NumberAxis xAxis = new NumberAxis();
        final NumberAxis yAxis = new NumberAxis();
        xAxis.setLabel("Number of Month");
        //creating the chart
        final LineChart<Number,Number> lineChart = 
                new LineChart<Number,Number>(xAxis,yAxis);

        lineChart.setTitle("Stock Monitoring, 2010");
        //defining a series
        XYChart.Series series = new XYChart.Series();
        series.setName("My portfolio");
        //populating the series with data
        series.getData().add(new XYChart.Data(1, 23));
        series.getData().add(new XYChart.Data(2, 14));
        series.getData().add(new XYChart.Data(3, 15));
        series.getData().add(new XYChart.Data(4, 24));
        series.getData().add(new XYChart.Data(5, 34));
        series.getData().add(new XYChart.Data(6, 36));
        series.getData().add(new XYChart.Data(7, 22));
        series.getData().add(new XYChart.Data(8, 45));
        series.getData().add(new XYChart.Data(9, 43));
        series.getData().add(new XYChart.Data(10, 17));
        series.getData().add(new XYChart.Data(11, 29));
        series.getData().add(new XYChart.Data(12, 25));

        Scene scene  = new Scene(lineChart,800,600);
        lineChart.getData().add(series);

        stage.setScene(scene);
        stage.show();
    }

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

For example I want to get this result:

http://dev.sencha.com/deploy/ChartsDemo/examples/chart/Live%20Animated.html

How I can modify the Line chart to get the same result? Is there already made example?

P.S I tested this example to animate the Line Chart

import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.animation.AnimationTimer;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.AreaChart;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.stage.Stage;


public class MainApp extends Application {

    private static final int MAX_DATA_POINTS = 50;
    private int xSeriesData = 0;
    private XYChart.Series series1;
    private XYChart.Series series2;
    private XYChart.Series series3;
    private ExecutorService executor;
    private AddToQueue addToQueue;
    private ConcurrentLinkedQueue<Number> dataQ1 = new ConcurrentLinkedQueue<Number>();
    private ConcurrentLinkedQueue<Number> dataQ2 = new ConcurrentLinkedQueue<Number>();
    private ConcurrentLinkedQueue<Number> dataQ3 = new ConcurrentLinkedQueue<Number>();

    private NumberAxis xAxis = new NumberAxis();
    final NumberAxis yAxis = new NumberAxis();
    final LineChart<Number,Number> lineChart =
                new LineChart<Number,Number>(xAxis,yAxis);

    private void init(Stage primaryStage) {
        xAxis = new NumberAxis(0,MAX_DATA_POINTS,MAX_DATA_POINTS/10);
        xAxis.setForceZeroInRange(false);
        xAxis.setAutoRanging(false);

        xAxis.setTickLabelsVisible(false);
        xAxis.setTickMarkVisible(false);
        xAxis.setMinorTickVisible(false);


        NumberAxis yAxis = new NumberAxis();
        yAxis.setAutoRanging(true);

        //-- Chart
        final LineChart<Number, Number> sc = new LineChart<Number, Number>(xAxis, yAxis) {
            // Override to remove symbols on each data point
            @Override protected void dataItemAdded(Series<Number, Number> series, int itemIndex, Data<Number, Number> item) {}
        };
        sc.setAnimated(false);
        sc.setId("liveLineeChart");
        sc.setTitle("Animated Line Chart");

        //-- Chart Series
        series1 = new XYChart.Series<Number, Number>();
        series2 = new XYChart.Series<Number, Number>();
        series3 = new XYChart.Series<Number, Number>();
        lineChart.getData().addAll(series1, series2, series3);

        series1.setName("Test 1");
        series2.setName("Test 2");
        series3.setName("Test 3");



        primaryStage.setScene(new Scene(lineChart));
    }





    @Override public void start(Stage stage) {
        stage.setTitle("Animated Line Chart Sample");
        init(stage);
        stage.show();


        executor = Executors.newCachedThreadPool(new ThreadFactory() {
            @Override public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                return thread;
            }
        });
        addToQueue = new AddToQueue();
        executor.execute(addToQueue);
        //-- Prepare Timeline
        prepareTimeline();


    }

    private class AddToQueue implements Runnable {
        @Override
        public void run() {
            try {
                // add a item of random data to queue
                dataQ1.add(Math.random());
                dataQ2.add(Math.random());
                dataQ3.add(Math.random());

                Thread.sleep(1000);
                executor.execute(this);
            } catch (InterruptedException ex) {
                Logger.getLogger(MainApp.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }

  //-- Timeline gets called in the JavaFX Main thread
    private void prepareTimeline() {
        // Every frame to take any data from queue and add to chart
        new AnimationTimer() {
            @Override public void handle(long now) {
                addDataToSeries();
            }
        }.start();
    }

    private void addDataToSeries() {
        for (int i = 0; i < 20; i++) { //-- add 20 numbers to the plot+
            if (dataQ1.isEmpty()) break;
            series1.getData().add(new AreaChart.Data(xSeriesData++, dataQ1.remove()));
            series2.getData().add(new AreaChart.Data(xSeriesData++, dataQ2.remove()));
            series3.getData().add(new AreaChart.Data(xSeriesData++, dataQ3.remove()));
        }
        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series1.getData().size() > MAX_DATA_POINTS) {
            series1.getData().remove(0, series1.getData().size() - MAX_DATA_POINTS);
        }
        if (series2.getData().size() > MAX_DATA_POINTS) {
            series2.getData().remove(0, series2.getData().size() - MAX_DATA_POINTS);
        }
        if (series3.getData().size() > MAX_DATA_POINTS) {
            series3.getData().remove(0, series3.getData().size() - MAX_DATA_POINTS);
        }
        // update
        xAxis.setLowerBound(xSeriesData-MAX_DATA_POINTS);
        xAxis.setUpperBound(xSeriesData-1);
    }


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

The code it's not working properly because only new value are added. Old values are not destroyed.

Answer 1

Based on JewelSea's example on AnimatedAreaChart, I modified it to make a similar example for you based on LineGraph. Please have a look at the example, hope it satisfies your need!

import javafx.animation.AnimationTimer;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.stage.Stage;

import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;


public class AnimatedLineChart extends Application {

    private static final int MAX_DATA_POINTS = 50;
    private int xSeriesData = 0;
    private XYChart.Series<Number, Number> series1 = new XYChart.Series<>();
    private XYChart.Series<Number, Number> series2 = new XYChart.Series<>();
    private XYChart.Series<Number, Number> series3 = new XYChart.Series<>();
    private ExecutorService executor;
    private ConcurrentLinkedQueue<Number> dataQ1 = new ConcurrentLinkedQueue<>();
    private ConcurrentLinkedQueue<Number> dataQ2 = new ConcurrentLinkedQueue<>();
    private ConcurrentLinkedQueue<Number> dataQ3 = new ConcurrentLinkedQueue<>();

    private NumberAxis xAxis;

    private void init(Stage primaryStage) {

        xAxis = new NumberAxis(0, MAX_DATA_POINTS, MAX_DATA_POINTS / 10);
        xAxis.setForceZeroInRange(false);
        xAxis.setAutoRanging(false);
        xAxis.setTickLabelsVisible(false);
        xAxis.setTickMarkVisible(false);
        xAxis.setMinorTickVisible(false);

        NumberAxis yAxis = new NumberAxis();

        // Create a LineChart
        final LineChart<Number, Number> lineChart = new LineChart<Number, Number>(xAxis, yAxis) {
            // Override to remove symbols on each data point
            @Override
            protected void dataItemAdded(Series<Number, Number> series, int itemIndex, Data<Number, Number> item) {
            }
        };

        lineChart.setAnimated(false);
        lineChart.setTitle("Animated Line Chart");
        lineChart.setHorizontalGridLinesVisible(true);

        // Set Name for Series
        series1.setName("Series 1");
        series2.setName("Series 2");
        series3.setName("Series 3");

        // Add Chart Series
        lineChart.getData().addAll(series1, series2, series3);

        primaryStage.setScene(new Scene(lineChart));
    }


    @Override
    public void start(Stage stage) {
        stage.setTitle("Animated Line Chart Sample");
        init(stage);
        stage.show();


        executor = Executors.newCachedThreadPool(new ThreadFactory() {
            @Override
            public Thread newThread(Runnable r) {
                Thread thread = new Thread(r);
                thread.setDaemon(true);
                return thread;
            }
        });

        AddToQueue addToQueue = new AddToQueue();
        executor.execute(addToQueue);
        //-- Prepare Timeline
        prepareTimeline();
    }

    private class AddToQueue implements Runnable {
        public void run() {
            try {
                // add a item of random data to queue
                dataQ1.add(Math.random());
                dataQ2.add(Math.random());
                dataQ3.add(Math.random());

                Thread.sleep(500);
                executor.execute(this);
            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }
        }
    }

    //-- Timeline gets called in the JavaFX Main thread
    private void prepareTimeline() {
        // Every frame to take any data from queue and add to chart
        new AnimationTimer() {
            @Override
            public void handle(long now) {
                addDataToSeries();
            }
        }.start();
    }

    private void addDataToSeries() {
        for (int i = 0; i < 20; i++) { //-- add 20 numbers to the plot+
            if (dataQ1.isEmpty()) break;
            series1.getData().add(new XYChart.Data<>(xSeriesData++, dataQ1.remove()));
            series2.getData().add(new XYChart.Data<>(xSeriesData++, dataQ2.remove()));
            series3.getData().add(new XYChart.Data<>(xSeriesData++, dataQ3.remove()));
        }
        // remove points to keep us at no more than MAX_DATA_POINTS
        if (series1.getData().size() > MAX_DATA_POINTS) {
            series1.getData().remove(0, series1.getData().size() - MAX_DATA_POINTS);
        }
        if (series2.getData().size() > MAX_DATA_POINTS) {
            series2.getData().remove(0, series2.getData().size() - MAX_DATA_POINTS);
        }
        if (series3.getData().size() > MAX_DATA_POINTS) {
            series3.getData().remove(0, series3.getData().size() - MAX_DATA_POINTS);
        }
        // update
        xAxis.setLowerBound(xSeriesData - MAX_DATA_POINTS);
        xAxis.setUpperBound(xSeriesData - 1);
    }

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

N.B. I haven't taken care of updating the values on the X-axis, you can do that !