软件简介

解决iOS 7中短时间内连续push或者pop view动画操作而产生崩溃的bug。
bug描述原因为 Can’t add self as subview。可以用下面这段代码重现这个bug：

- (void)viewWillAppear:(BOOL)animated
{
 [super viewWillAppear:animated];
 UIViewController *vc = [[UIViewController alloc] init];
 [self.navigationController pushViewController:vc animated:YES];
}

将会得到以下错误:
2014-07-03 11:54:25.051 Demo[2840:60b] nested push animation can result in
corrupted navigation bar 2014-07-03 11:54:25.406 Demo[2840:60b] Finishing up a
navigation transition in an unexpected state. Navigation Bar subview tree
might get corrupted.