如何添加动作到UIAlertController并获得动作的结果(Swift)

Question

我想建立一个UIAlertController，有四个动作按钮，按钮的标题设置为"红心"，"黑桃"，"方块"one_answers"梅花"。当按钮被按下时，我想返回它的标题。

总之，这是我的计划:

// TODO: Create a new alert controller
for i in ["hearts", "spades", "diamonds", "clubs"] {
    // TODO: Add action button to alert controller
    // TODO: Set title of button to i
}
// TODO: return currentTitle() of action button that was clicked

Answer 1

试试这个:

let alert = UIAlertController(title: "Alert Title", message: "Alert Message", style = .Alert)
for i in ["hearts", "spades", "diamonds", "hearts"] {
    alert.addAction(UIAlertAction(title: i, style: .Default, handler: doSomething)
}
self.presentViewController(alert, animated: true, completion: nil)

和处理动作在这里:

func doSomething(action: UIAlertAction) {
    //Use action.title
}

为将来的参考，你应该看看苹果的文档ualertcontrollers

Answer 2

下面是一个示例代码，包含两个action +和ok-action:

import UIKit
// The UIAlertControllerStyle ActionSheet is used when there are more than one button.
@IBAction func moreActionsButtonPressed(sender: UIButton) {
    let otherAlert = UIAlertController(title: "Multiple Actions", message: "The alert has more than one action which means more than one button.", preferredStyle: UIAlertControllerStyle.ActionSheet)
    let printSomething = UIAlertAction(title: "Print", style: UIAlertActionStyle.Default) { _ in
        print("We can run a block of code." )
    }
    let callFunction = UIAlertAction(title: "Call Function", style: UIAlertActionStyle.Destructive, handler: myHandler)
    let dismiss = UIAlertAction(title: "OK", style: UIAlertActionStyle.Cancel, handler: nil)
    // relate actions to controllers
    otherAlert.addAction(printSomething)
    otherAlert.addAction(callFunction)
    otherAlert.addAction(dismiss)
    presentViewController(otherAlert, animated: true, completion: nil)
}
func myHandler(alert: UIAlertAction){
    print("You tapped: (alert.title)")
}}

与e.g. handler: myHandler定义一个函数，读取结果.

这只是一种方法;-)

有什么问题吗?