How to implement selection of Nodes in JavaFX

Question

I am very new JavaFX, started learning it yesterday. Spent the whole day reading through the documentation, but learned nothing...

Here is what I want to do, make a

Answer 1

This is how I did it... Simple and Easy

Main Class

public class Lab05 extends Application {

    @Override
    public void start(Stage primaryStage) {
        double width = 400;
        double height = 400;

        int num_of_circles = 5;
        int radius_of_circles = 20;

        BorderPane root = new BorderPane();

        for (int i = 0; i < num_of_circles; i++) {
            MyCircle temp = createCircle(radius_of_circles, (50 * i) + 1, 100);
            temp.setFrame(width, height);
            root.getChildren().add(temp.getCircle());
            temp.getCircle().addEventFilter(MouseEvent.ANY, temp);
        }

        Scene scene = new Scene(root, width, height);

        primaryStage.setTitle("Lab 05");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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

    public static MyCircle createCircle(int radius, int x, int y){
        MyCircle circle = new MyCircle();
        circle.setCircle(radius, x, y);
        return circle;
    }
}

MyCircle Class

public class MyCircle implements EventHandler{
    private static double frameX = 0;
    private static double frameY = 0;
    private final Circle circle = new Circle();
    private static final List CIRCLES = new ArrayList<>();

    public void setCircle(int radius, int x, int y){
        circle.setRadius(radius);
        position(x,y);
        circle.setStrokeWidth(3);
        circle.setStroke(Color.valueOf("white"));
        CIRCLES.add(circle);
    }

    public void setFrame(double x, double y){
        frameX = x;
        frameY = y;
    }

    public Circle getCircle(){
        return circle;
    }

    public void position(double x, double y){
        if ( x < frameX && x > 0)
            circle.setCenterX(x);
        if ( y < frameY && y > 0)
            circle.setCenterY(y);
    }

    public void selected(){
        CIRCLES.stream().forEach((c) -> {
            c.setStroke(Color.valueOf("white"));
        });
        circle.setStroke(Color.valueOf("orange"));
    }

    public void unselected() {
        circle.setStroke(Color.valueOf("white"));
    }

    @Override
    public void handle(MouseEvent event) {
        if (event.getEventType() == MouseEvent.MOUSE_PRESSED){
            selected();
        }
        else if (event.getEventType() == MouseEvent.MOUSE_DRAGGED){
            position(event.getX(), event.getY());
        }
    }
}