whose view is not in the window hierarchy

视图层级混乱造成的 打开控制器的方式present 与push 都不行，可以执行下面的方法

- (UIViewController *)goBackForViewController{

    UIViewController *topRootViewController = [UIApplication sharedApplication].keyWindow.rootViewController;

    while (topRootViewController.presentedViewController)

    {

        topRootViewController = topRootViewController.presentedViewController;

    }

    return topRootViewController;

}

调用  [[self goBackForViewController] presentViewController:新创建的控制器(或者push)];

[topRootViewController presentViewController:nav animated:NO completion:nil];

whose view is not in the window hierarchy

原文：http://www.cnblogs.com/tryFighting/p/6398828.html