title: How to erase previous drawing on Canvas?
body: <p>I have a background image (a map) on which I need to regularly draw the you-are-here icon. I use Canvas to draw the icon on top of the map. Assuming that the drawing process is triggered on button click (see code below), how can I erase the previous drawing?</p>
  
  <pre><code>private void displayUserPos(Point userPos) {
      Bitmap marker = BitmapFactory.decodeResource(getResources(), R.drawable.ic_yah);
      canvas.drawBitmap(marker, (float)userPos.getX(), (float)userPos.getY(), null);
      imgView.setImageBitmap(fmOverlay);
  }
  </code></pre>