How to add Id to canvas on Android?

Question

I need to add a circle across the canvas every time I click a button (identical behavior to Paint from Windows). But to move the circle clicked on the screen I need an Id. Does anyone have any idea where I can add this Id? Thanks in advance.

Answer 1

The easiest way to do this is to create a Custom View. Not to mention that this will probably avoid Boilerplate in your code.

private class CircleCanvas extends View {

    public CircleCanvas(Context context) {
        super(context);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        ...
        createCircle(...)
    }

}

And when creating the circle in your code, use the method View#setId().

CircleCanvas circle = new CircleCanvas(ctx);
circle.setId(CIRCLE_ID);