解决:https://blog.gocy.tech/2016/11/19/iOS-touch-handling/
1. tap.delegate = self; tap加个代理<UIGestureRecognizerDelegate>
2.
//UITapGestureRecognizer 和 UICollectionView 冲突 - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch { if ([touch.view isDescendantOfView:self.collectionView]) { return NO; } return YES; }