First, the SmileyBouncing exampleis not mine it's Erels'.
It's a good trick but I want to learn another "perfect" solution for this problem.
What do you mean with 'perfect' solution.
Why do you mean that the ImageView principle is 'not perfect' ?
For me it's the most efficient method.
I don't think that extracting and saving the portion of the background bitmap of the activity that is behind the images and, at each image change, draw the background, draw the new image and invalidate the rectangle of the concerned activity area is the most efficient nor 'perfect'.
But, well, that's only my opinion.
Best regards.