新建controller底色透明

//当前vc
self.definesPresentationContext = YES;

//目标vc
tovc.modalPresentationStyle = UIModalPresentationOverCurrentContext;

//目标vc的底色透明
tovc.view.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.0];

//跳转
[self presentViewController:tovc animated:NO completion:nil];