title: Custom Seekbar with masking effect with two drawables?
body: <p>I am using a custom seekbar to show a graph. I had done till this. I am showing this graph by applying a background drawable to the seekbar. Now my problem is, I need to set the blue one as progress drawable and need to set the background of seekbar as the red graph. So that when progress happens thumb moves over red the area where thumb passed should be changed to blue color like a masking effect. Can any one tell the best possible way to do this. My pictures are shown below <img src="https://i.stack.imgur.com/TWONJ.png" alt="Secondary progress"><img src="https://i.stack.imgur.com/6VQ9m.png" alt="Background"></p>