Xcode中的可重用*按鈕*

Question

我已經創建了一個actionSheet，其中包含3個選項，可以推送到其他視圖控制器並調用一個數字。該選項位於我的應用程序的每個屏幕上的導航欄上的按鈕上。我試圖找到一種重用代碼的方式，而不必爲每個屏幕重新輸入代碼。我知道有一種方法可以通過子類化UIButton來完成此操作，但我已經搜索了幾天，並且無法找到關於如何實際編寫子類的明確答案。現在我的代碼如下：

class moreButton: UIButton { 

@IBAction func displayActionSheet(_ sender: Any) { 
    let alertController = UIAlertController(title: nil, message: "Get Your Roast On", preferredStyle: .actionSheet) 
     let followAction = UIAlertAction(title: "Follow Us", style: .default, handler: {(action: UIAlertAction!)->Void in self.performSegue(withIdentifier: "moveSegue", sender: self) 
    }) 
     let shopAction = UIAlertAction(title: "Visit Shop", style: .default, handler: {(action: UIAlertAction!)->Void in self.performSegue(withIdentifier: "shopSegue", sender: self) 
    }) 
     let callAction = UIAlertAction(title: "Call Us Now", style: .default) { _ in 
      let url:URL = URL(string: "tel://number")! 
      UIApplication.shared.open(url, options: [:], completionHandler: nil) 

    } 

    let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil) 

    alertController.addAction(followAction) 
    alertController.addAction(shopAction) 
    alertController.addAction(callAction) 
    alertController.addAction(cancel) 


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

，我發現了錯誤：

value of type 'moreButton' has no member 'performSegue'

同時在followAction和shopAction線和「型‘moreButton’的值沒有任何成員‘存在’ 「在最後一行。當我直接從按鈕創建IBAction時，此代碼正在工作，但現在它似乎有錯誤，我不知道如何糾正。

Answer 1

你會得到這些錯誤，因爲performSegue和present是UIViewController方法。

而不是繼承UIButton，我會創建一個新的助手類，用類方法爲您構建UIAlertController。該方法將接受UIViewController作爲其參數，以便它可以正確構建UIAlertAction。

你會從displayActionSheet喜歡把這種新的方法：

let alertController = ActionSheetBuilder.build(viewController: self) 
present(alert, animated: true, completion: nil) 

適應你的創作代碼粘貼到新的類會出來這樣的：

final class ActionSheetBuilder { 
    class func build(viewController: UIViewController) -> UIAlertController { 
     let alertController = UIAlertController(title: nil, message: "Get Your Roast On", preferredStyle: .actionSheet) 
     let followAction = UIAlertAction(title: "Follow Us", style: .default, handler: {(action: UIAlertAction!)->Void in viewController.performSegue(withIdentifier: "moveSegue", sender: viewController) }) 
     let shopAction = UIAlertAction(title: "Visit Shop", style: .default, handler: {(action: UIAlertAction!)->Void in viewController.performSegue(withIdentifier: "shopSegue", sender: viewController) }) 
     let callAction = UIAlertAction(title: "Call Us Now", style: .default) { _ in 
      let url:URL = URL(string: "tel://2845471035")! 
      UIApplication.shared.open(url, options: [:], completionHandler: nil) 
     } 
     let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil) 

     alertController.addAction(followAction) 
     alertController.addAction(shopAction) 
     alertController.addAction(callAction) 
     alertController.addAction(cancel) 

     return alertController 
    } 
}