当按“返回"时，如何在 navigationController 中重新加载 rootViewController? [英] How to reload rootViewController in navigationController When press "back"?

问题描述

一个 navigationController 中有 2 个 viewController:navigationController->root->A在viewController A中，如果用户进行一些设置并按下左栏按钮项目(返回)，我希望根视图更新其布局(某些视图的大小将被更改).

There are 2 viewControllers in a navigationController: navigationController->root->A In viewController A, if a user make some settings and press the left bar button item(Back), I want the root view to renew its layout(some views' size will be changed).

现在，我通过在两个 viewControllers 之间添加一个更多的 navigationController(以模态呈现)来使它工作:navigationController->root->navigationController->A.

By now, I make it works by adding one more navigationController between the two viewControllers(present modally): navigationController->root->navigationController->A.

有没有办法用一个导航控制器更新根视图控制器?(截图 1)

Is there a way to renew the root viewController with one navigationController?(Screenshot 1)

谢谢.

----- 已编辑-----

----- Edited -----

示例代码:

override func viewWillAppear(_ animated: Bool) {

    creatButtons()

}

func createButtons(){

    let button1 = UIButton()
    ........
    let button2 = UIButton()
    ........
    .......

}

如果我在viewWillAppear()下创建了16个按钮，从A回来的时候所有的按钮都会被复制吗?它们的大小都需要更新.

If I create 16 buttons under viewWillAppear(), will all the buttons be duplicated when comes back from A? Their size are all need to be renewed.

推荐答案

不确定我是否正确理解您的问题，但这里有两种关于如何处理这种情况的替代方案:

Not sure if I understood your question correctly but here are two alternatives on how to handle this scenario:

如果您想在 A 中更改设置时刷新 root 的视图层次结构，只需确保将更改保留在 root 和 A 可以访问.覆盖root中的-viewWillAppear:(也会在返回"时触发)方法，每次都根据设置布局视图.

If you want to refresh the view hierarchy of root when settings are changed in A just make sure to persist the changes in a place that both root and A can access. Override the -viewWillAppear: (will be triggered on "back" as well) method in root and layout the view according to the settings every time.

其他选择:

您可以为由 root 实现的 A 创建一个 delegate protocol 并将 root 分配为 >A 的 delegate 当 root 实例化或呈现 A 时.

You could create a delegate protocol for A that is implemented by root and assign root as A's delegate when root instantiates or presents A.

A 然后会调用它的委托 (root) 来通知它更改并让 root 更新它的视图.

A would then invoke its delegate (root) to inform it about the change and let root update its views.

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