why my code “Bouncing ball” doesn't work?

Question

I\'m trying to write a code a bout a bouncing ball, but i\'m stuck in how to make the ball bounced. The code seems correct, no wrong messages from eclipse and yet the ball d

Answer 1

you never declared that the g.fillOval was the ball here do this...

g.drawOval((int)applex, (int)appley, (int)appleradius, appleradius);
  public double applex = ArandomX; //replace the random with values..
    public double appley = ArandomY; //same here
    public int appleradius = 10;

this makes it move...

a.px += a.vx;
        // check for boundaries
        if (a.px >= this.getWidth() || a.px <= 0) {
            // reverse vel and apply
            a.vx = -a.vx;
            a.px += -a.vx; // to prevent sticking
        }

        //a.vx += -gravity; // add this constant to accelerate things down
        a.py += a.vy;
        // check for boundaries
        if (a.py >= this.getHeight() || a.py <= 0) {
            // reverse vel and apply
            a.vy = -a.vy;
            a.py += a.vy; // to prevent sticking
        }`

replace a.vx with your x or dx idk because your variables are unclear and yeah just replace a.vy with either y or dy and do the same for my px... it will work