ios - 类 func 中的 UITextViewDelegate

Question

我正在使用 swift 3，我有一个类如下:

class Assistor : NSObject , UITextViewDelegate {


private override init() {

}

class func RegisterTextView(uiview:UIView) {

    if let RegisteredView = uiview as? UITextView {
        RegisteredView.delegate = self as! UITextViewDelegate
    }
}


func textViewDidBeginEditing(_ textView: UITextView) {
    print("Begin")
}

func textViewDidEndEditing(_ textView: UITextView) {
    print("End")
}
}

在普通的 uiviewcontroller 中，我想在 viewDidLoad 中像这样调用 Assistor 函数:

class InqueryDetailsViewController: UIViewController {
    @IBOutlet weak var AnswerTextView:UITextView!
override func viewDidLoad() {
    super.viewDidLoad()

Assistor.RegisterTextView(uiview: AnswerTextView)
}
}

很明显，我想从助手而不是 uiviewcontroller 触发 textViewDidBeginEditing。怎么做？

Answer 1

首先你的 Assistor 必须声明为对象，如果你只想要一个你可以将它作为单例，你需要将 init 更改为 public，并将 registerTextView 更改为实例方法

试试这个

class Assistor : NSObject , UITextViewDelegate {

    //Singleton
     static let sharedInstance: Assistor = Assistor()

    override init() {
        super.init()
    }

    func registerTextView(uiview:UIView) {
        if let RegisteredView = uiview as? UITextView {
            RegisteredView.delegate = self as! UITextViewDelegate
        }
    }


    func textViewDidBeginEditing(_ textView: UITextView) {
        print("Begin")
    }

    func textViewDidEndEditing(_ textView: UITextView) {
        print("End")
    }
}

使用它

class ViewController: UIViewController {

    @IBOutlet weak var textView: UITextView!

    var assistor : Assistor = Assistor()

    override func viewDidLoad() {
        super.viewDidLoad()

        self.assistor.registerTextView(uiview: self.textView)
        //using as singleton
        //Assistor.sharedInstance.registerTextView(uiview: self.textView)
    }
}

希望对你有帮助