JavaFX 2.x : How to draw parallel line? - charts

Question

This code below draw lines on an XY lineChart
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.chart.CategoryAxis;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.scene.control.Label;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Line;
import javafx.scene.shape.LineTo;
import javafx.scene.shape.MoveTo;
import javafx.scene.shape.Path;
import javafx.stage.Stage;
public class Lines extends Application {
Path path;
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage stage) {
final CategoryAxis xAxis = new CategoryAxis();
final NumberAxis yAxis = new NumberAxis(0.5, 9.5, 0.1);
yAxis.setTickUnit(1);
//yAxis.setPrefWidth(35);
yAxis.setMinorTickCount(10);
yAxis.setTickLabelFormatter(new NumberAxis.DefaultFormatter(yAxis) {
#Override
public String toString(Number object) {
String label;
label = String.format("%7.2f", object.floatValue());
return label;
}
});
final LineChart<String, Number> lineChart = new LineChart<String, Number>(xAxis, yAxis);
lineChart.setCreateSymbols(false);
lineChart.setAlternativeRowFillVisible(false);
lineChart.setLegendVisible(false);
XYChart.Series series1 = new XYChart.Series();
series1.getData().add(new XYChart.Data("Jan", 1));
series1.getData().add(new XYChart.Data("Feb", 4.5));
series1.getData().add(new XYChart.Data("Mar", 2.5));
series1.getData().add(new XYChart.Data("Apr", 6.5));
series1.getData().add(new XYChart.Data("May", 4.5));
series1.getData().add(new XYChart.Data("Jun", 8.5));
series1.getData().add(new XYChart.Data("Jul", 6.5));
BorderPane bp = new BorderPane();
bp.setCenter(lineChart);
Scene scene = new Scene(bp, 800, 600);
lineChart.setAnimated(false);
lineChart.getData().addAll(series1);
Lines.MouseHandler mh = new Lines.MouseHandler( bp );
bp.setOnMouseClicked( mh );
bp.setOnMouseMoved( mh );
stage.setScene(scene);
path = new Path();
path.setStrokeWidth(1);
path.setStroke(Color.BLACK);
scene.setOnMouseDragged(mh);
scene.setOnMousePressed(mh);
bp.getChildren().add(path);
stage.setScene(scene);
stage.show();
}
class MouseHandler implements EventHandler< MouseEvent > {
private boolean gotFirst = false;
private Line line;
private Pane pane;
private double x1, y1, x2, y2;
public MouseHandler( Pane pane ) {
this.pane = pane;
}
#Override
public void handle( MouseEvent event ) {
if( event.getEventType() == MouseEvent.MOUSE_CLICKED ) {
if( !gotFirst ) {
x1 = x2 = event.getX();
y1 = y2 = event.getY();
line = new Line( x1, y1, x2, y2 );
pane.getChildren().add( line );
gotFirst = true;
}
else {
line = null;
gotFirst = false;
}
}
else {
if( line != null ) {
x2 = event.getX();
y2 = event.getY();
// update line
line.setEndX( x2 );
line.setEndY( y2 );
}
}
}
}
}
I would like to copy (clone) a line once drawn, such as this picture
So, first left mouse click on point 1, then second mouse click on point 2: my goal is to have now a copy of this line (same lenght, same slope) that I can place anywhere on the chart, in this example by a third left mouse click on point 3.
How to do this?
Thanks!