如何在 Swift 中为多个 UIActionSheet 创建通用方法

Question

我正在设置一个 UIViewController 和 2 UIButtons。每个按钮都有一个功能，显示 UIAlertController 和几个选项。可以创建一个通用方法来避免两个函数中的代码重复吗？

我已经尝试创建一个参数类型为 UIAlertController 的函数，但我无法使用该参数。

我在这里创建了一个示例来向您展示我尝试重构的内容：

func showFirstMenu(){

    let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

    let optionOne = UIAlertAction(title: "Option 1", style: .default) { action in
        self.performSegue(withIdentifier: "optionOne", sender: self)
    }

    let optionTwo = UIAlertAction(title: "Option 2", style: .default) { action in
        self.performSegue(withIdentifier: "optionTwo", sender: self)
    }

    actionSheet.addAction(optionOne)
    actionSheet.addAction(optionTwo)
    actionSheet.addAction(cancel)

    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad ){
        actionSheet.popoverPresentationController?.sourceView = self.view
        actionSheet.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        actionSheet.popoverPresentationController?.permittedArrowDirections = []
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPad")
    }
    else{
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPhone")
    }
}

func showSecondMenu(){

    let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

    let optionThree = UIAlertAction(title: "Option 3", style: .default) { action in
        self.performSegue(withIdentifier: "optionThree", sender: self)
    }

    let optionFour = UIAlertAction(title: "Option 4", style: .default) { action in
        self.performSegue(withIdentifier: "optionFour", sender: self)
    }

    actionSheet.addAction(optionThree)
    actionSheet.addAction(optionFour)
    actionSheet.addAction(cancel)

    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad ){
        actionSheet.popoverPresentationController?.sourceView = self.view
        actionSheet.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        actionSheet.popoverPresentationController?.permittedArrowDirections = []
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPad")
    }
    else{
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPhone")
    }
}

有什么方法可以减少代码量吗？或者这是声明 UIActionSheet ?

的唯一方法

感谢您阅读本文。

Answer 1

解决方案一：

如果您的 AlertViewController 的操作将始终有 segue 执行，您可以使用结构和可变参数显着减少重复，如下所示：

struct Option {
    var name: String
    var segueIdentifier: String
}

func configureActionSheet(options: Option...) {
    let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
    actionSheet.addAction(cancel)

    for option in options {
        let currentOption = UIAlertAction(title: option.name, style: .default) { action in
            self.performSegue(withIdentifier: option.segueIdentifier, sender: self)
        }
        actionSheet.addAction(currentOption)
    }

    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad ){
        actionSheet.popoverPresentationController?.sourceView = self.view
        actionSheet.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        actionSheet.popoverPresentationController?.permittedArrowDirections = []
    }

    self.present(actionSheet, animated: true, completion: nil)
}

func showMenu1() {
    let option1 = Option(name: "Option 1", segueIdentifier: "optionOne")
    let option2 = Option(name: "Option 2", segueIdentifier: "optionTwo")
    self.configureActionSheet(options: option1, option2)
}

方案二：

如果您的 AlertViewController 的操作总是不同，那么您无能为力，但仍然可以避免重复，如下所示：

func configureActionSheet() -> UIAlertController {
    let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
    actionSheet.addAction(cancel)

    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad ){
        actionSheet.popoverPresentationController?.sourceView = self.view
        actionSheet.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        actionSheet.popoverPresentationController?.permittedArrowDirections = []
    }

    return actionSheet
}


func showFirstMenu() {
    let optionOne = UIAlertAction(title: "Option 1", style: .default) { action in
        self.performSegue(withIdentifier: "optionOne", sender: self)
    }

    let optionTwo = UIAlertAction(title: "Option 2", style: .default) { action in
        self.performSegue(withIdentifier: "optionTwo", sender: self)
    }

    let actionSheet = configureActionSheet()
    actionSheet.addAction(optionOne)
    actionSheet.addAction(optionTwo)
    self.present(actionSheet, animated: true, completion: nil)
}

Answer 2

你可以这样写一个函数

func presentActionsheetWithOptions(title:String, msg: String, options:[String:String], isCancelRequired:Bool) {

    let actionSheet = UIAlertController(title: title, message: msg, preferredStyle: .actionSheet)

    for (header,seg) in options {
        let optionOne = UIAlertAction(title: header, style: .default) { action in
            self.performSegue(withIdentifier: seg, sender: self)
        }
        actionSheet.addAction(optionOne)

    }
    if(isCancelRequired) {
        let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
        actionSheet.addAction(cancel)

    }
    if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad ){
        actionSheet.popoverPresentationController?.sourceView = self.view
        actionSheet.popoverPresentationController?.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
        actionSheet.popoverPresentationController?.permittedArrowDirections = []
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPad")
    }
    else{
        self.present(actionSheet, animated: true, completion: nil)
        print("Display on iPhone")
    }
}

像这样调用函数

        presentActionsheetWithOptions(title: "test", msg: "testmsg", options: ["option1":"optionone","option2":"optiontwo"], isCancelRequired: true);

决定应该是可选的变量

Answer 3

您可以像这样在每个 UIButton 中设置一个标签：

//For the first button
UIButton.tag = 1

//For the second button
UIButton.tag = 2

然后，您将此标记传递到您的菜单函数中，创建一个包含您的 UIAlertAction 标题和标识符的数组，循环它们并使用 switch 方法将适当的操作添加到警报中：

  func showMenu(sender: UIButton) {
     let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
     let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

     let titles = ["Option 1", "Option 2", "Option 3", "Option 4"]
     let identifiers = ["optionOne","optionTwo","optionThree","optionFour"]
     let tags = [1,1,2,2] //match the button tag with the array index

     for (index, title) in titles.enumerated(){
        if sender.tag == tags[index] {
           let action = self.getAction(title: title, identifier:identifiers[index])
           actionSheet.addAction(action)
        }
      }
      actionSheet.addAction(cancel)
  }

  func getAction(title: String, identifier: String) -> UIAlertAction {
      let action = (title: title, style: .default) { action in
         self.performSegue(withIdentifier: identifier, sender: self)
      }
      return action
  }

希望对您有所帮助！

如何在 Swift 中为多个 UIActionSheet 创建通用方法

How to create a general method for multiple UIActionSheet in Swift

uikit

ios

swift

uialertcontroller