ios - 使用 presentingViewController 关闭 viewController

Question

我有三个 ViewController，它的顺序是(A present B which presents C)， 当我留在 C viewController 中时，我必须将 ViewController 解散到 B viewController。

对于C viewController，它的presentingViewCONtroller是B viewController

当然，我可以用

[self dismissViewControllerAnimated:YES completion:NULL];//self means C ViewController

但我想知道我还可以使用以下方法:

[self.presentingViewController dismissViewControllerAnimated:YES completion:NULL];

因为C的presentingViewController是B的ViewController，但是效果是一样的。 self 表示 C ViewController 而 self.presentingViewController 表示 B ViewController，但它们也做了同样的工作

第二个问题是我不能使用下面的命令连续关闭两个 viewController:

  [self dismissViewControllerAnimated:YES completion:^{
    [self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:NULL];
}]; //self means C viewController

感谢您的帮助!

Answer 1

of course ,I can use

[self dismissViewControllerAnimated:YES completion:NULL];//self means C ViewController

这只会忽略 C，而不是您想要的 B。

But I was wondering I can also use the following method:

[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:NULL];

是的，这行得通。如有疑问，请尝试一下。

The second question is I cannot use the following to dismiss two viewController in succession:

[self dismissViewControllerAnimated:YES completion:^{
    [self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:NULL];
}]; //self means C viewController

这不是问题。不管怎样，它不起作用的原因是在你解雇自己之后，你的 presentingViewController 是 nil。您需要将其存储在一个临时变量中。

UIViewController *gp = self.presentingViewController.presentingViewController;
[self dismissViewControllerAnimated:YES completion:^{
    [gp dismissViewControllerAnimated:YES completion:nil];
    [self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil];
}];

当然，两者会有不同的动画，你需要决定你喜欢哪个。