Swift 中的闭包数组

Question

我有一个接受 Array 参数的函数。该数组将由各种闭包组成。如何获取闭包数组并在函数内访问该数组？

func showAlert(_ title: String, message: String, actions: [String], handler: [()->()]) -> Void {

}

Alertift.alert(title: "test",
                           message: "test")
                .action(.default("OK")) {

                }
               .action(.default("Cancel")) {

                }
                .show(on: self)

现在在我的函数中，我将接收到动作的数量和关联的处理程序或闭包的数量。现在如何使用数组将每个动作分配给闭包。

Answer 1

在你的方法中访问闭包：

func showAlert(_ title: String, message: String, actions: [String], handler: [()->()]) -> Void {
    for closure in handler {
        closure()
    }
}

将您的方法与闭包数组一起使用：

showAlert("foo", message: "bar", actions: ["foo", "bar"], handler: [{
        print("foo")
        }, {
        print("bar")
        }
    ])

Answer 2

以下应该有效。因为我不想安装库，所以我没有对此进行全面测试，但无论如何你应该明白这一点：

func showAlert(_ title: String, message: String, actions: [String], handler: [()->()]) -> Void {
    let alert = Alertift.alert(title: title, message: message)
    for (action, handler) in zip(actions, handler) {
        alert.action(.default(action), handler: handler)
    }
}

请注意，将Strings 与操作直接分组会更好：

func showAlert(_ title: String, message: String, actionsAndHandlers: [(String, ()->())]) -> Void {
    let alert = Alertift.alert(title: title, message: message)
actionsAndHandlers.forEach {
        alert.action(.default($0.0), handler: $0.1)
    }
}

Answer 3

在 @RohitaxRajguru 的情况下，以下内容应适用于 Alertift v2.0 和 Swift 3。

func showAlert(_ title: String, message: String, actions: [String], @escaping handler: [()->()]) -> Void {
    Alertift.alert(title: title, message: message)
        .actions(actions) { _, index, _ in
            handler[index]()
        }
        .show(on: self)
}

// ===============
showAlert("Foo", messge: "bar bazz.", actions: ["A", "B", "C"], handler: [
    {
        print("A selected")
    },
    {
        print("B selected")
    },
    {
        print("C selected")
    }
])

https://github.com/sgr-ksmt/Alertift

Answer 4

我想你要实现的是这个，看看共享文件-

drive

import Foundation
import UIKit

class Alert {

    var okAction : AlertSuccess?
    typealias AlertSuccess = (()->())?

    public func show(title : String?, message : String?, viewController : UIViewController?, okAction : AlertSuccess = nil) {

        let version : NSString = UIDevice.current.systemVersion as NSString
        if  version.doubleValue >= 8 {
            let alert:UIAlertController = UIAlertController(title: title, message: message, preferredStyle:.alert)
            alert.addAction(UIAlertAction(title: "OK".localized, style: .default, handler: { (action: UIAlertAction) in

                if let okAction = okAction {
                    okAction()
                }
            }))
            viewController?.present(alert, animated:true, completion:nil);
        }
    }

    public func showWithCancelAndOk(title : String, okTitle : String, cancelTitle : String, message : String, viewController : UIViewController?, okAction : AlertSuccess = nil, cancelAction : AlertSuccess = nil) {
        let version:NSString = UIDevice.current.systemVersion as NSString;

        if  version.doubleValue >= 8 {
            let alert:UIAlertController = UIAlertController(title: title, message: message, preferredStyle:.alert)

            alert.addAction(UIAlertAction(title: cancelTitle, style: .default, handler: { (action: UIAlertAction) in

                if let cancelAction = cancelAction {
                    cancelAction()
                }
            }))
            alert.addAction(UIAlertAction(title: okTitle, style: .default, handler: { (action: UIAlertAction) in

                if let okAction = okAction {
                    okAction()
                }
            }))
            viewController?.present(alert, animated:true, completion:nil);
        }
    }
}