如何在使用Swift反转Segue时在iOS中传递信息？ [英] How to Pass information Back in iOS when reversing a Segue using Swift?

问题描述

我有两个视图控制器，一个和两个。我从VC One转到VC Two。在VC Two上，我选择了一些存储在数组中的数据。当我按下导航栏上的后退按钮时，我想将该阵列发送回VC One。

I have two view controllers, One and Two. I go from VC One to VC Two. On VC Two, I select some data that I store in an array. When I press the "Back" button on the navigation bar, I would like to send that array back to VC One.

使用Swift和放大器的最佳方法是什么;故事板？

What's the best way to do this using Swift & Storyboards?

谢谢！

推荐答案

如果您要呈现模态使用完成和取消按钮查看（有点像选择器），在展开segue方法期间获取值可能是最简单的。

If you were presenting a modal view with Done and Cancel buttons (sort of like a picker), grabbing the value during an unwind segue method would probably be the easiest.

鉴于您要使用导航控制器的本机后退按钮，最佳做法可能是实现VC One可以符合的协议，然后更新VC One一旦选择了VC Two上的数据。类似于：

Given that you want to use the navigation controller's native Back button, the best practice would probably be to implement a protocol that VC One can conform to, and then update VC One as soon as the data on VC Two is selected. Something like:

在VCTwo.swift中：

In VCTwo.swift:

protocol VCTwoDelegate {
    func updateData(data: String)
}

class VCTwo : UIViewController {
    var delegate: VCTwoDelegate?
    ...
    @IBAction func choiceMade(sender: AnyObject) {
        // do the things
        self.delegate?.updateData(self.data)
    }
    ...
}

和VCOne.swift：

and in VCOne.swift:

class VCOne: ViewController {
    ...
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "VCTwoSegue" {
            (segue.destinationViewController as VCTwo).delegate = self
        }
    }
    ...
}

extension VCOne: VCTwoDelegate {
    func updateData(data: String) {
        self.internalData = data
    }
}

这篇关于如何在使用Swift反转Segue时在iOS中传递信息？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！