Android drawing - Background caching

Question

Quick question - I'm having control that's extending LinearLayout and I'm overriding it's onPaint method like this

@Override
protected void onDraw(Canvas canvas) {

    super.dispatchDraw(canvas);

    _background.draw(canvas);
    _object1.draw(canvas);
    _object2.draw(canvas);
    _object3.draw(canvas);

    // etc...

}

Every 40ms I invoke postInvalidate() in background and onPaint gets called on UI thread. The problem is _background.draw is taking over 80% of my drawing time.

So - is it possible to somehow cache background and not redraw it every time?

Answer 1

You can specify a region to postInvalidate() to control the area that gets redrawn.