UITextField未更新以更改ObservableObject（SwiftUI）

我正在尝试创建一个UITextView，用于编辑值

currentDisplayedAddress

。其他视图也会更改该值，我希望UITextView在发生这种情况时更新其文本

视图初始化正确，我可以从

AddressTextField

编辑

currentDisplayedAddress

，没有问题，并触发相关视图更新。但是，当值被其他视图更改时，文本字段的文本不会更改，即使

textField.text

在

updateUIView

中打印正确的更新值，其他视图也会相应更新

我不知道这可能是什么原因。非常感谢您的帮助

struct AddressTextField: UIViewRepresentable {
    private let textField = UITextField(frame: .zero)
    var commit: () -> Void
    @EnvironmentObject var userData: UserDataModel

    func makeUIView(context: UIViewRepresentableContext<AddressTextField>) -> UITextField {
        textField.text = self.userData.currentDisplayedAddress
        textField.delegate = context.coordinator
        return textField
    }

    func updateUIView(_ uiView: UITextField, context: UIViewRepresentableContext<AddressTextField>) {
        if self.textField.text != self.userData.currentDisplayedAddress {
        DispatchQueue.main.async {
            self.textField.text = self.userData.currentDisplayedAddress
            }
        }
    }

   (...)

    func makeCoordinator() -> Coordinator { Coordinator(self) }

    class Coordinator: NSObject, UITextFieldDelegate {
        var addressTextField: AddressTextField

        func textFieldShouldReturn(_ textField: UITextField) -> Bool {   //delegate method
            textField.resignFirstResponder()
            addressTextField.userData.currentDisplayedAddress = textField.text ?? String()
            addressTextField.commit()
            return true
        }
    }
}

struct AddressTextField:UIViewRepresentable{
私有let textField=UITextField（帧：.0）
var commit:（）->Void
@EnvironmentObject var userData:UserDataModel
func makeUIView（上下文：UIViewRepresentableContext）->UITextField{
textField.text=self.userData.currentDisplayedAddress
textField.delegate=context.coordinator
返回文本字段
}
func updateUIView（uiView:UITextField，context:UIViewRepresentableContext）{
如果self.textField.text！=self.userData.currentDisplayedAddress{
DispatchQueue.main.async{
self.textField.text=self.userData.currentDisplayedAddress
}
}
}
(...)
func makeCoordinator（）->Coordinator{Coordinator（self）}
类协调器：NSObject，UITextFieldDelegate{
var addressTextField:addressTextField
func textField应该返回（textField:UITextField）->Bool{//delegate方法
textField.resignFirstResponder（）辞职
addressTextField.userData.currentDisplayedAddress=textField.text？？字符串（）
addressTextField.commit（）
返回真值
}
}
}

您不应该将

UITextField

创建为属性，因为在父级更新期间可以重新创建

AddressTextField

结构。

makeUIView

正是创建UI实例的地方，representable代表您处理其引用

这里是固定变量。使用Xcode 11.4/iOS 13.4进行测试

struct AddressTextField: UIViewRepresentable {
    var commit: () -> Void = {}
    @EnvironmentObject var userData: UserDataModel

    func makeUIView(context: UIViewRepresentableContext<AddressTextField>) -> UITextField {
        let textField = UITextField(frame: .zero)
        textField.text = self.userData.currentDisplayedAddress
        textField.delegate = context.coordinator
        return textField
    }

    func updateUIView(_ textField: UITextField, context: UIViewRepresentableContext<AddressTextField>) {
        if textField.text != self.userData.currentDisplayedAddress {
            textField.text = self.userData.currentDisplayedAddress
        }
    }

    func makeCoordinator() -> Coordinator { Coordinator(self) }

    class Coordinator: NSObject, UITextFieldDelegate {
        var addressTextField: AddressTextField
        init(_ addressTextField: AddressTextField) {
            self.addressTextField = addressTextField
        }
        func textFieldShouldReturn(_ textField: UITextField) -> Bool {   //delegate method
            textField.resignFirstResponder()
            addressTextField.userData.currentDisplayedAddress = textField.text ?? String()
            addressTextField.commit()
            return true
        }
    }
}

struct AddressTextField:UIViewRepresentable{
var commit:（）->Void={}
@EnvironmentObject var userData:UserDataModel
func makeUIView（上下文：UIViewRepresentableContext）->UITextField{
设textField=UITextField（帧：.0）
textField.text=self.userData.currentDisplayedAddress
textField.delegate=context.coordinator
返回文本字段
}
func updateUIView（textField:UITextField，context:UIViewRepresentableContext）{
如果textField.text！=self.userData.currentDisplayedAddress{
textField.text=self.userData.currentDisplayedAddress
}
}
func makeCoordinator（）->Coordinator{Coordinator（self）}
类协调器：NSObject，UITextFieldDelegate{
var addressTextField:addressTextField
init（uAddressTextField:addressTextField）{
self.addressTextField=addressTextField
}
func textField应该返回（textField:UITextField）->Bool{//delegate方法
textField.resignFirstResponder（）辞职
addressTextField.userData.currentDisplayedAddress=textField.text？？字符串（）
addressTextField.commit（）
返回真值
}
}
}

您不应该将

UITextField

创建为属性，因为在父级更新期间可以重新创建

AddressTextField

结构。

makeUIView

正是创建UI实例的地方，representable代表您处理其引用

这里是固定变量。使用Xcode 11.4/iOS 13.4进行测试

struct AddressTextField: UIViewRepresentable {
    var commit: () -> Void = {}
    @EnvironmentObject var userData: UserDataModel

    func makeUIView(context: UIViewRepresentableContext<AddressTextField>) -> UITextField {
        let textField = UITextField(frame: .zero)
        textField.text = self.userData.currentDisplayedAddress
        textField.delegate = context.coordinator
        return textField
    }

    func updateUIView(_ textField: UITextField, context: UIViewRepresentableContext<AddressTextField>) {
        if textField.text != self.userData.currentDisplayedAddress {
            textField.text = self.userData.currentDisplayedAddress
        }
    }

    func makeCoordinator() -> Coordinator { Coordinator(self) }

    class Coordinator: NSObject, UITextFieldDelegate {
        var addressTextField: AddressTextField
        init(_ addressTextField: AddressTextField) {
            self.addressTextField = addressTextField
        }
        func textFieldShouldReturn(_ textField: UITextField) -> Bool {   //delegate method
            textField.resignFirstResponder()
            addressTextField.userData.currentDisplayedAddress = textField.text ?? String()
            addressTextField.commit()
            return true
        }
    }
}

struct AddressTextField:UIViewRepresentable{
var commit:（）->Void={}
@EnvironmentObject var userData:UserDataModel
func makeUIView（上下文：UIViewRepresentableContext）->UITextField{
设textField=UITextField（帧：.0）
textField.text=self.userData.currentDisplayedAddress
textField.delegate=context.coordinator
返回文本字段
}
func updateUIView（textField:UITextField，context:UIViewRepresentableContext）{
如果textField.text！=self.userData.currentDisplayedAddress{
textField.text=self.userData.currentDisplayedAddress
}
}
func makeCoordinator（）->Coordinator{Coordinator（self）}
类协调器：NSObject，UITextFieldDelegate{
var addressTextField:addressTextField
init（uAddressTextField:addressTextField）{
self.addressTextField=addressTextField
}
func textField应该返回（textField:UITextField）->Bool{//delegate方法
textField.resignFirstResponder（）辞职
addressTextField.userData.currentDisplayedAddress=textField.text？？字符串（）
addressTextField.commit（）
返回真值
}
}
}