OOP Program-18

(18) Write a program that moves a circle up, down, left or right using arrow keys.

  

Program Code:

 import javafx.application.Application;

import javafx.scene.Scene;

import javafx.scene.shape.Circle;

import javafx.scene.layout.Pane;

import javafx.geometry.Insets;

import javafx.stage.Stage;

public class OOP_18 extends Application 

{

 @Override 

 public void start(Stage primaryStage) {

  Pane pane = new Pane();

  pane.setPadding(new Insets(30, 30, 30, 30));

  Circle circle = new Circle(30, 30, 30);

  pane.getChildren().add(circle);

  pane.setOnKeyPressed(e -> {

   switch (e.getCode()) {

    case UP : circle.setCenterY(circle.getCenterY() > 

     circle.getRadius() ? circle.getCenterY() - 15 :

     circle.getCenterY()); break;

    case DOWN : circle.setCenterY(circle.getCenterY() < 

     pane.getHeight() - circle.getRadius() ? 

     circle.getCenterY() + 15 : circle.getCenterY()); 

     break;

    case LEFT : circle.setCenterX(circle.getCenterX() >

     circle.getRadius() ? circle.getCenterX() - 15 :

     circle.getCenterX()); break;

    case RIGHT : circle.setCenterX(circle.getCenterX() <

     pane.getWidth() - circle.getRadius() ?

     circle.getCenterX() + 15: circle.getCenterX());

   }

  });

  Scene scene = new Scene(pane, 200, 200);

  primaryStage.setTitle("OOP_18"); 

  primaryStage.setScene(scene); 

  primaryStage.show(); 

  pane.requestFocus();

 }

}

Output:

1) Default output:

2) 
Circle is moved after we press up, down, left or right arrow keys: