Opacity on a background Drawable image in View (using XML Layout)
I ended up just going with the programmatical solution, since it doesn't look like it can be done via the XML layouts.
Drawable rightArrow = getResources().getDrawable(R.drawable.green_arrow_right_small);// setting the opacity (alpha)rightArrow.setAlpha(10);// setting the images on the ImageViewsrightImage.setImageDrawable(rightArrow);