自定义标题为AlertAction iOS

Question

我正在尝试为alertAction的AlertController创建一个自定义标题，其条件函数取决于不同switches的状态：

let alert = UIAlertController(title: “Got it”, message: “Please, select:”, preferredStyle: UIAlertControllerStyle.Alert)


name01: String = "name01"
name02: String = "name02"
name03: String = "name03" 

if switch01.on {
        let action01 = UIAlertAction(title: name01, style: .Default) { (_) in }
    }
    if switch02.on {
        let action02 = UIAlertAction(title: name02, style: .Default) { (_) in }
    }
    if switch03.on {
        let action03 = UIAlertAction(title: name03, style: .Default) { (_) in }
    }



    let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel) { (_) in }

    alert.addAction(action01)//Cannot convert value of type 'String' to expected argument type 'UIAlertAction'
    alert.addAction(action02)//Cannot convert value of type 'String' to expected argument type 'UIAlertAction'
    alert.addAction(action03)//Cannot convert value of type 'String' to expected argument type 'UIAlertAction'
    alert.addAction(cancelAction)//No error

提前致谢。

Answer 1

您需要在if块外创建AlertController的Action ，因为在if block它们不可访问，还需要使用if条件来像这样确定标题。

name01: String = "name01"
name02: String = "name02"
name03: String = "name03" 

if switch01.on {
    name01 = "Title Chanhed"
}
if switch02.on {
    name02 = "Title Chanhed"
}
if switch03.on {
    name03 = "Title Chanhed"
}
let action01 = UIAlertAction(title: name01, style: .Default) { (_) in }
let action02 = UIAlertAction(title: name02, style: .Default) { (_) in }
let action03 = UIAlertAction(title: name03, style: .Default) { (_) in }
alert.addAction(action01)
alert.addAction(action02)
alert.addAction(action03)
alert.addAction(cancelAction)

另外，如果您要基于标题执行动作，则可以在动作处理程序中像这样比较标题。

let action01 = UIAlertAction(title: name01, style: .Default) { (action:UIAlertAction) in 
     if action.title == "name01" {

     }
     else {

     }
}