ce1002.a12.s101201046

A12.java

package ce1002.a12.s101201046;

import java.awt.event.*;
import java.awt.*;
import javax.swing.*;

public class A12 extends KeyAdapter {
    static JFrame jf;

    static { //initial JFrame
        jf = new JFrame("A12");
        jf.getContentPane().setLayout(null);
        jf.getContentPane().setPreferredSize(new Dimension(500, 500));
        jf.setLocation(300, 300);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.setVisible(true);
        jf.requestFocusInWindow();
        jf.pack();
    }

    public static void main(String[] args) {
        jf.addKeyListener(new A12()); //set keylistener
    }

    public void keyPressed(KeyEvent e) {
        new Thread(new MovingButton()).start(); //create thread
    }
}

MovingButton.java

package ce1002.a12.s101201046;

import javax.swing.*;
import static java.lang.Math.*;

public class MovingButton extends JButton implements Runnable {
    private double dx, dy;
    private int bounceCounter = 0;

    /*** initial **/
    public MovingButton() {
        double r = random() * PI;
        dx = cos(r) * 3.0;
        dy = sin(r) * 3.0;
        A12.jf.getContentPane().add(this);
        this.setBounds((int)(random()*(getParent().getWidth() - 50)),
                       (int)(random()*(getParent().getHeight() - 50)),
                        50, 50);
        this.setText(String.valueOf(bounceCounter));
    }

    //thread run
    public void run() {
        try {
            while(true) {
                Thread.sleep(10);
                setLocation(getX() + (int)dx, getY() + (int)dy);
                
                //wall collision check
                if (getX() < 0 || getX() > (getParent().getWidth() - getWidth())) {
                    dx = -dx;
                    setText(String.valueOf(++bounceCounter));
                }

                if (getY() < 0 || getY() > (getParent().getHeight() - getHeight())) {
                    dy = -dy;
                    setText(String.valueOf(++bounceCounter));
                }

            }   
        } catch(InterruptedException e) {
            e.printStackTrace();    
        }   
    }
}