下一个模态出现后，立即解雇或删除以前模态显示的视图控制器 [英] Dismiss or remove previous modally presented view controller as soon as the next one appear modally

问题描述

我的目标包括很多视图，需要根据每个用户操作以模态呈现不同的视图.这是我想要做的事情，以获得更清晰的视图层次结构和更好的用户体验.

My target include a lot view need to present different view modally base on each user action. Here what I want to do to get cleaner view hierarchy and better user experience.

1. 根视图控制器以模态形式存在第一个View Controller
2. 当我单击第一视图控制器"上的按钮时，第二视图控制器将以模态形式显示在其上方.
3. 第二个View Controller出现后，我想从视图层次结构中删除或删除第一个.

1. Root View Controller present First View Controller modally
2. When I clicked button on the First View Controller, then the Second View Controller appear modally over it.
3. As soon as the Second View Controller did appear, I want to dismiss or remove the first one from view hierarchy.

我可以这样做吗? 如果是这样，我应该怎么做?

Can I do that? If so, how should i do it?

如果不是，什么是解决此问题的正确方法，因为我将在每个视图上呈现许多模态呈现的视图控制器.我认为，即使我要关闭当前视图，在关闭当前视图时仍会保留前一个视图.

If not, what is the right way to solve this out cause I will present many modally presented view controllers over each view. I think even if I want to dismiss current view, the previous one will still remain appear when current one dismiss.

更新:

VC1(根目录)> VC 2(以模态形式出现)> VC 3(以前是 通过VC 2模态呈现)

当我关闭VC3时，VC2仍在视图内存中.因此，我不想在退出VC3后立即显示VC2，而是希望通过从视图层次结构中删除或取消VC2来看到VC1.

When i dismiss VC3, the VC2 is still on view memory. So, I don't want to appear VC2 as soon as I dismiss VC3 and instead I want to see VC1 by removing or dismissing VC2 from view hierarchy.

Want :在图像上，当我关闭蓝色时，我不想在视图内存中看到粉红色，我想在蓝色出现后立即将其删除

WANT : At the image, when I dismiss the blue,I don't want see the pink in my view memory and I want to remove it as soon as the blue one appear.

这就是我想要做的.

有帮助吗?

推荐答案

所以，我们假设您有一个类似于以下内容的故事板:

So, let's assume that you have a storyboard similar to:

应该发生的是:

• 呈现第二个ViewController(来自第一个ViewController).
• 呈现第三个ViewController(来自第二个ViewController).
• 从第三个ViewController释放到第一个ViewController.

在第三个ViewController按钮的操作中:

In the third ViewController button's action:

@IBAction func tapped(_ sender: Any) {
    presentingViewController?.presentingViewController?.dismiss(animated: true, completion: nil)
}

如您所见，通过访问当前版本的 presentingViewController ViewController，您可以关闭视图控制器的先前层次结构:

As you can see, by accessing the presentingViewController of the current ViewController, you can dismiss the previous hierarchy of the view controllers:

展示此视图控制器的视图控制器.

The view controller that presented this view controller.

实现presentingViewController?.presentingViewController?意味着:当前ViewController的呈现:)

By implementing presentingViewController?.presentingViewController? that means that: the presented of the presented current ViewController :)

这似乎有点令人困惑，但它非常简单.

It might seem a little bit confusing, but it is pretty simple.

所以输出应该是这样的(我在viewControllers中添加了背景色-如vc1:橙色，vc2:黑色和vc3:浅橙色-以使其清晰可见):

So the output should be like (I added background colors to the viewControllers -as vc1: orange, vc2: black and vc3: light orange- to make it appears clearly):

如果您要删除中间的ViewController(在此示例中为第二个ViewController)，请

If you are asking to remove the ViewController(s) in the middle (which in this example the second ViewController), dismiss(animated:completion:) does this automatically:

如果您连续显示多个视图控制器，则构建一个 呈现的视图控制器的堆栈，在视图上调用此方法 堆栈中较低的控制器取消其直接子视图 控制器和堆栈上该子项之上的所有视图控制器. 发生这种情况时，动画中仅关闭最顶层的视图 时尚;只需将所有中间视图控制器从 堆.最顶层的视图使用其模态过渡被消除 样式，可能与其他视图控制器使用的样式不同 在堆栈中较低的位置.

If you present several view controllers in succession, thus building a stack of presented view controllers, calling this method on a view controller lower in the stack dismisses its immediate child view controller and all view controllers above that child on the stack. When this happens, only the top-most view is dismissed in an animated fashion; any intermediate view controllers are simply removed from the stack. The top-most view is dismissed using its modal transition style, which may differ from the styles used by other view controllers lower in the stack.

参考您的要求:

我认为，即使我想关闭当前视图，上一个也会 当前的一个解雇仍然存在.

I think even if I want to dismiss current view, the previous one will still remain appear when current one dismiss.

我认为这在UI上很明显(并且我觉得还可以)，但是正如dismiss文档讨论中所提到的，第三个和第二个都将从堆栈中删除.这是正确的方法.

I think that appears clearly on the UI (and I find it ok), but as mentioned in the dismiss documentation discussion, both the third and the second will be removed from the stack. That's the right way.

这篇关于下一个模态出现后，立即解雇或删除以前模态显示的视图控制器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！