How to detect double touch in UIButton inside of a UIScrollView

Question

Hi,

In my exercise app, i have a 10 x 10 grid of large UIButtons. and then I added that UIButtons in a UIView, then I added that UIView in a UIScrollView so that I can scroll or pinch or expand. Now my problem is when every time I pinch or expand gesture in the UIScrollView sometimes I tap two UIButtons and execute at the same time. How can I detect double touch or tap in the UIButtons?

Thanks.