don't know how to call the Canvas' setPoint() method ?

Question about the task

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Cannot access it from Ball ? Do I need to create a new Canvas object each time in the Ball.draw() method ? Then call the newly created canvas object's setPoint() ? Makes no sense ? Second question: The original creation requirement for Ball, had another constructor. Had to modify it now with this task's requirements, but what happens to the local variables ? I mean, I assume (because I'm not certain) that I still have to pass variables to the superclass (BaseObject), so what do i do with my local dx and dy variables ? Also increase them ? Currently, this is my constructor: public Ball(double x, double y, double speed, double direction) { super(x, y, 1); this.speed = speed; this.direction = direction; this.dx = x; this.dy = y; isFrozen = true; }

The Ball class is missing something:

First, you need to implement the move() method inherited from BaseObject:
a) x should increase by dx each turn
b) y must increase by dy each turn
If the ball is frozen, then x and y should not change

Second, you need to implement the draw(Canvas canvas) method:
You need to call the canvas object's setPoint method with arguments (x, y, 'O')

Third, you need to implement the start() method
This call "thaws" the ball.
You decide for yourself what you need to do to accomplish this.

P.S. Oh, I almost forgot! The x, y, and radius fields are declared with the private access modifier in the BaseObject class,
which isn't very convenient. Change the modifier to protected so that all of the BaseObject class's descendants can control their own
coordinates and dimensions without the need to use "foreign" getters and setters.

Requirements:

The Ball class's move() method should increment the value of x by dx if the isFrozen field is false.
The Ball class's move() method should increment the value of y by dy if the isFrozen field is false.
The Ball class's move method should not change the values of the x and y fields if the isFrozen field is true.
The Ball class must implement the draw(Canvas canvas) method according to the task conditions.
The Ball class must implement a start() method that sets the isFrozen field to false.
The access modifier of the x field in the BaseObject class must be changed to protected.
The access modifier of the y field in the BaseObject class must be changed to protected.
The access modifier of the radius field in the BaseObject class must be changed to protected.

package com.codegym.task.task24.task2413; import java.util.List; public class Arkanoid { private int width; private int height; private Ball ball; private Paddle paddle; private List<Brick> bricks; public static Arkanoid game; public Arkanoid(int width, int height) { this.width = width; this.height = height; } public int getWidth() { return width; } public int getHeight() { return height; } public void setWidth(int width) { this.width = width; } public void setHeight(int height) { this.height = height; } public Ball getBall() { return ball; } public Paddle getPaddle() { return paddle; } public List<Brick> getBricks() { return bricks; } public void setBall(Ball ball) { this.ball = ball; } public void setPaddle(Paddle paddle) { this.paddle = paddle; } public void setBricks(List<Brick> bricks) { this.bricks = bricks; } public void run(){ } public void move(){ } public static void main(String[] args){ } }

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Johannes

Level 27 , Centurion, Pretoria, South-Africa

4 May 2020, 10:07

no worries. I was having a blonde moment. The Ball's draw() method receives a Canvas object, which I can use to call the setPoint() method. Just a tip: the setPoint parameters are the super's x, y and the LETTER "O", not the number.