I Have bad performance on using shadow effect

Question

I put some image views on scroll view. And when I drag this scroll view, I didn\'t have any problems.

But after I applied shadow effect to these image views, dragging th

Answer 1

Whenever you work with shadows its better to use a bezier path as the background. This will help you set the shadowPath, which will drastically improve performance. Rasterize will improve performance, but setShadowPath will improve 5x more than just setting rasterize.

path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, 100, 100) cornerRadius:10];
[self.layer setShadowColor:[UIColor blackColor].CGColor];
[self.layer setShadowOpacity:1.0f];
[self.layer setShadowRadius:10.0f];
[self.layer setShadowPath:[path CGPath]];