ios - 将状态/绑定(bind)传递给 UIViewRepresentable

Question

将状态变量传递给我的自定义文本字段的正确方法是什么？我希望避免其他方法/可观察的。这不应该工作吗？

我在示例项目中重新创建了以下问题。

import SwiftUI

struct ParentView: View {
    @State var text: String = "initial"
    var body: some View {
        VStack {
            ChildView(text: $text)
            Text(self.text)
        }
    }
}
struct ChildView: View {
    @Binding var text: String
    var body: some View {
        MyTextField(text: $text).frame(width: 300, height: 40, alignment: .center)
    }
}

struct MyTextField: UIViewRepresentable {
    @Binding var text: String
    func makeUIView(context: Context) -> UITextField {
        let view = UITextField()
        view.borderStyle = UITextField.BorderStyle.roundedRect
        return view
    }
    func updateUIView(_ uiView: UITextField, context: Context) {
        uiView.text = text
    }
}

Answer 1

创建 @Binding您的 CustomTextField 中的属性(property)像:

struct CustomTextField: UIViewRepresentable {
    @Binding var text: String 
}

初始化您的 @Binding位于 init() 的属性(property)像:

init(text: Binding<String>) {
    self._text = text
}

通过text属性(property)给 UITextField像:

func makeUIView(context: Context) -> UITextField {
    // Customise the TextField as you wish
    textField.text = text        
    return textField
}

更新 text的 UITextField像:

func updateUIView(_ uiView: UITextField, context: Context) {
    uiView.text = self.text
}

更新 @Binding带有用户输入文本的属性，例如:

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    if let value = textField.text as NSString? {
    let proposedValue = value.replacingCharacters(in: range, with: string)
        parent.text = proposedValue as String // Here is updating
    }
    return true
}

您的 ContentView应该看起来像:

struct ContentView: View {
    @State var text: String = ""
    var body: some View {
        CustomTextField(text: $text)
    }
}

现在好了，如果你想要 CustomTextField 的完整代码然后看this answer .