Listing 28.10, ConnectedCircles.java, allows the user to create circles and determine whether they are connected. Rewrite the program for rectangles. The program lets the user create a rectangle by clicking a mouse in a blank area that is not currently covered by a rectangle. As the rectangles are added, the rectangles are repainted as filled if they are connected or are unfilled otherwise, as shown in Figure 28.25b?c.

Listing

(b) (c) 1 import javafx.application. Application; 2 import javafx.geometry.Point2D; 3 import javafx.scene.Node; 4 import javafx.scene.Scene; 5 import javafx.scene.layout.Pane; 6 import javafx.scene.paint.Color; 7 import javafx.scene.shape.Circle; 8 import javafx.stage.Stage; 10 public class ConnectedCircles extends Application { 11 12 13 14 15 16 17 18 19 @Override // Override the start method in the Application class public void start(Stage primaryStage) { // Create a scene and place it in the stage Scene scene = new Scene(new CirclePane(), 450, 350); primaryStage.setTitle("ConnectedCircles"); // Set the stage title primaryStage.setScene(scene); // Place the scene in the stage primaryStage.show(); // Display the stage /** Pane for displaying circles */ class CirclePane extends Pane { 20 21 public CirclePane () { this.setOnMouseClicked(e -> { if (!isInsideACircle(new Point2D(e.getX(), e.getY()))) { // Add a new circle getChildren ().add(new Circle(e.getX(), e.getY(), 20)); colorIfConnected(); 22 23 24 25 26 27 28 29 }); 30