Movement of UIButton which is in the UIScrollview becomes slow after pinching/zooming out

I have UIButtons in UIScrollview and also UIScrollview contains Imageview too. If i move UIButtons, particular area of the image within that UIButtons arranged will be colored.. Its happening well but my problem is movement of individual buttons are happening well If image is in normal size. and movemen开发者_运维技巧t is getting delayed once after pinching or zooming..

Can anyone tell the reason why this is happening?

Thanks and Regards, V.Karuna.

This kind of issue is usually down to the level of processing effort on the phone. Having to clip obscured views, and deal with transparency slows things down a lot. Make sure that you set everything you can to be opaque. This can make a massive difference. (opaque is a property of UIView therefore inherited by all controls, buttons etc)