Android :: Set Image / Background Source Dynamically

Is there any possibility to set background image dynamically? I try to explain what I mean.

String picVariable = getPictureFromServer();
ImageView image = (ImageView)v.findViewById(R.id.dynamic_image);
// I know, that doesn't work, but that's the way I looking for
image.setBackgroundResource(picVariable);

I also read this article. It would suggested in one answer, to use java reflection to get a field of the R class by name. But I've never used reflextion before.