private void createChart() {
    xAxis = new NumberAxis();
    xAxis.setForceZeroInRange(false);
    xAxis.setAutoRanging(true);
    xAxis.setLabel(priceColumnLabel.get());

    yAxis = new NumberAxis();
    yAxis.setForceZeroInRange(false);
    yAxis.setAutoRanging(true);
    yAxis.setLabel("Amount in BTC");
    yAxis.setTickLabelFormatter(new NumberAxis.DefaultFormatter(yAxis, "", ""));

    seriesBuy = new XYChart.Series();
    seriesBuy.setName("Offers for  buy bitcoin  ");

    seriesSell = new XYChart.Series();
    seriesSell.setName("Offers for sell bitcoin");

    areaChart = new AreaChart<>(xAxis, yAxis);
    areaChart.setAnimated(false);
    areaChart.setId("charts");
    areaChart.setMinHeight(300);
    areaChart.setPadding(new Insets(0, 30, 10, 0));
    areaChart.getData().addAll(seriesBuy, seriesSell);
  }
 protected AreaChart<Number, Number> createChart() {
   final NumberAxis xAxis = new NumberAxis(0, 128, 8);
   final NumberAxis yAxis = new NumberAxis(0, 50, 10);
   final AreaChart<Number, Number> ac = new AreaChart<Number, Number>(xAxis, yAxis);
   // setup chart
   ac.setId("audioAreaDemo");
   ac.setLegendVisible(false);
   ac.setTitle("Live Audio Spectrum Data");
   ac.setAnimated(false);
   xAxis.setLabel("Frequency Bands");
   yAxis.setLabel("Magnitudes");
   yAxis.setTickLabelFormatter(new NumberAxis.DefaultFormatter(yAxis, null, "dB"));
   // add starting data
   XYChart.Series<Number, Number> series = new XYChart.Series<Number, Number>();
   series.setName("Audio Spectrum");
   //noinspection unchecked
   series1Data = new XYChart.Data[(int) xAxis.getUpperBound()];
   for (int i = 0; i < series1Data.length; i++) {
     series1Data[i] = new XYChart.Data<Number, Number>(i, 50);
     series.getData().add(series1Data[i]);
   }
   ac.getData().add(series);
   return ac;
 }