set a random color in draw method

Question

Ok so this is a shape drawn with a random color, however I'd like that shape to stay that color while being repainted. Right now with this draw method it just draws a new random color every repaint() so it looks like a rainbow shape. How would I make it grab a random color then stick with that for that particular shape?

public void draw(Graphics g) {
    g.setColor(new Color(randomNum.nextInt(256), randomNum.nextInt(256), randomNum.nextInt(256)));
    g.fillOval((int)getX(),(int)getY(), getRadius(), getRadius());

}

Answer 1

By saving the color you're drawing. So you'll only randomly generate it once, and then keep using that color to redraw each time.

Either generate it before the draw like Color c = new Color(randomNum.nextInt(256), randomNum.nextInt(256), randomNum.nextInt(256)); or only generate the variable and test if it has been initialized in your draw method. If it hasn't (the first time running your code), you generate a random color, if it has been initialized, you just skip generating the color and go straight to your g.fillOval

Answer 2

You keep a list of shapes. every shape has his color and radius.

when repaint, you draw every shape in the list.

static class OvalShape {Color color; int radius;}
List<OvalShape> shapeList = new ArrayList<>();

public void draw(Graphics g) {
    for(Shape s : shapeList) {
        g.setColor(s.color);
        g.fillOval((int)getX(),(int)getY(), s.radius, s.radius);
    }
}