swiftui 自定义 textfield

参考自BBCo
struct MyTextField:UIViewRepresentable{
    let placeholder:String?
    @Binding var text:String
    @Binding var showText:Bool
    let onCommit:()->Void
    
    init(placeholder:String? = nil,
         text:Binding<String>,
         showText:Binding<Bool>,
         onCommit:@escaping ()->Void = {}
    ){
        self.placeholder = placeholder
        self._text = text
        self._showText = showText
        self.onCommit = onCommit
    }
    
    
    func makeCoordinator() -> Coordinator {
        Coordinator(view: self)
    }
    
    class Coordinator:NSObject,UITextFieldDelegate{
        let parent:MyTextField
        init(view:MyTextField) {
            parent = view
        }
        func textFieldDidBeginEditing(_ textField: UITextField) {
            print("开始输入")
        }
        func textFieldShouldClear(_ textField: UITextField) -> Bool {
            print("textFieldShouldClear")
            return true
        }
        func textFieldShouldReturn(_ textField: UITextField) -> Bool {
            print("收起键盘")
            textField.endEditing(true)
            parent.onCommit()
            return true
        }
        func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
            //if return true ,can update ,if return false cannot update
            print(string)
            print(range)
            if string == "\n"{
                textField.endEditing(true)
               print("string == \n *********************** ")
            }
            return true
        }
        
    }
   
    
    func makeUIView(context: Context) -> UITextField {
        let view = UITextField()
        view.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        view.textColor = .black
        view.tintColor = .black
        view.text = text

        view.placeholder = placeholder
        view.adjustsFontSizeToFitWidth = true
        view.borderStyle = .none
        view.delegate = context.coordinator
        view.clearButtonMode = .whileEditing
        view.clearsOnBeginEditing = true
      
        return view
    }
    func updateUIView(_ uiView: UITextField, context: Context) {
        uiView.isSecureTextEntry = !showText
        print("updateUIView**************************** ")
    }
    
}