Using String Time stamps in LineChart - javafx

Question

I'm using JavaFX.
I've modified an example of a Zoom function on a LineChart. I get an exception when doing the zoom. I've figured out that there is a mismatch between Types on the xAxis, it wants Numbers and I'm using String Time stamps. How can I adapt this to work with time strings like "12:33:23" on xAxis?
package javafxapplication28;
import java.util.Collections;
import java.util.Random;
import static java.util.UUID.fromString;
import javafx.application.Application;
import javafx.beans.binding.BooleanBinding;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Point2D;
import javafx.geometry.Pos;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.chart.Axis;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart.Data;
import javafx.scene.chart.XYChart.Series;
import javafx.scene.control.Button;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
import javafx.beans.property.StringProperty;
import javafx.util.StringConverter;
public class JavaFXApplication28 extends Application {
private static final int NUM_DATA_POINTS = 1000 ;
#Override
public void start(Stage primaryStage) {
final LineChart<Number, Number> chart = createChart();
final StackPane chartContainer = new StackPane();
chartContainer.getChildren().add(chart);
final Rectangle zoomRect = new Rectangle();
zoomRect.setManaged(false);
zoomRect.setFill(Color.LIGHTSEAGREEN.deriveColor(0, 1, 1, 0.5));
chartContainer.getChildren().add(zoomRect);
setUpZooming(zoomRect, chart);
final HBox controls = new HBox(10);
controls.setPadding(new Insets(10));
controls.setAlignment(Pos.CENTER);
final Button zoomButton = new Button("Zoom");
final Button resetButton = new Button("Reset");
zoomButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
doZoom(zoomRect, chart);
}
});
resetButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
final NumberAxis xAxis = (NumberAxis)chart.getXAxis();
xAxis.setLowerBound(10);
xAxis.setUpperBound(200);
final NumberAxis yAxis = (NumberAxis)chart.getYAxis();
yAxis.setLowerBound(0);
yAxis.setUpperBound(200);
zoomRect.setWidth(0);
zoomRect.setHeight(0);
}
});
final BooleanBinding disableControls =
zoomRect.widthProperty().lessThan(5)
.or(zoomRect.heightProperty().lessThan(5));
zoomButton.disableProperty().bind(disableControls);
controls.getChildren().addAll(zoomButton, resetButton);
final BorderPane root = new BorderPane();
root.setCenter(chartContainer);
root.setBottom(controls);
final Scene scene = new Scene(root, 600, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
private LineChart<Number, Number> createChart() {
final NumberAxis xAxis = createAxis_x();
final NumberAxis yAxis = createAxis_y();
final LineChart<Number, Number> chart = new LineChart<>(xAxis, yAxis);
chart.setAnimated(false);
chart.setCreateSymbols(false);
chart.setData(generateChartData());
return chart ;
}
//Set range of x axis
private NumberAxis createAxis_x() {
final NumberAxis xAxis = new NumberAxis();
xAxis.setAutoRanging(false);
String xMin = "12:30:12";
String xMax = "13:21:01";
double xminDouble = Double.parseDouble(xMin);
double xmaxDouble = Double.parseDouble(xMax);
xAxis.setLowerBound(xminDouble);
xAxis.setUpperBound(xmaxDouble);
return xAxis;
}
//Set range of y axis
private NumberAxis createAxis_y() {
final NumberAxis yAxis = new NumberAxis();
yAxis.setAutoRanging(false);
String yMin = "40";
String yMax = "400";
double yminDouble = Double.parseDouble(yMin);
double ymaxDouble = Double.parseDouble(yMax);
yAxis.setLowerBound(yminDouble);
yAxis.setUpperBound(ymaxDouble);
return yAxis;
}
private ObservableList<Series<Number, Number>> generateChartData() {
final Series<Number, Number> series = new Series<>();
series.setName("Data");
final Random rng = new Random();
for (int i=0; i<NUM_DATA_POINTS; i++) {
Data<Number, Number> dataPoint = new Data<Number, Number>(i, rng.nextInt(1000));
series.getData().add(dataPoint);
}
return FXCollections.observableArrayList(Collections.singleton(series));
}
private void setUpZooming(final Rectangle rect, final Node zoomingNode) {
final ObjectProperty<Point2D> mouseAnchor = new SimpleObjectProperty<>();
zoomingNode.setOnMousePressed(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
mouseAnchor.set(new Point2D(event.getX(), event.getY()));
rect.setWidth(0);
rect.setHeight(0);
}
});
zoomingNode.setOnMouseDragged(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
double x = event.getX();
double y = event.getY();
rect.setX(Math.min(x, mouseAnchor.get().getX()));
rect.setY(Math.min(y, mouseAnchor.get().getY()));
rect.setWidth(Math.abs(x - mouseAnchor.get().getX()));
rect.setHeight(Math.abs(y - mouseAnchor.get().getY()));
}
});
}
private void doZoom(Rectangle zoomRect, LineChart<Number, Number> chart) {
Point2D zoomTopLeft = new Point2D(zoomRect.getX(), zoomRect.getY());
Point2D zoomBottomRight = new Point2D(zoomRect.getX() + zoomRect.getWidth(), zoomRect.getY() + zoomRect.getHeight());
final NumberAxis yAxis = (NumberAxis) chart.getYAxis();
Point2D yAxisInScene = yAxis.localToScene(0, 0);
final NumberAxis xAxis = (NumberAxis) chart.getXAxis();
System.out.println(xAxis);
Point2D xAxisInScene = xAxis.localToScene(0, 0);
double xOffset = zoomTopLeft.getX() - yAxisInScene.getX() ;
double yOffset = zoomBottomRight.getY() - xAxisInScene.getY();
double xAxisScale = xAxis.getScale();
double yAxisScale = yAxis.getScale();
xAxis.setLowerBound(xAxis.getLowerBound() + xOffset / xAxisScale);
xAxis.setUpperBound(xAxis.getLowerBound() + zoomRect.getWidth() / xAxisScale);
yAxis.setLowerBound(yAxis.getLowerBound() + yOffset / yAxisScale);
yAxis.setUpperBound(yAxis.getLowerBound() - zoomRect.getHeight() / yAxisScale);
System.out.println(yAxis.getLowerBound() + " " + yAxis.getUpperBound());
zoomRect.setWidth(0);
zoomRect.setHeight(0);
}
public static void main(String[] args) {
launch(args);
}
}
It works like this. Draw a rectangle in the Linechart for the area to zoom in. Then press the zoom button.
The sample code above gives an exception due to the problem with time strings. To get it to work use this instead:
String xMin = "40";
String xMax = "300";
Thanks for ur help!