Swift 按下一步后无法让文本字段切换焦点

我有一个文本视图列表，我想在按下一个键后切换焦点.我有一个 struct 体，它代表我的文本字段数据:

struct WordEntry : BaseIndexStruct, Identifiable, Equatable, Hashable{
    let id = UUID()
    var word : String = ""
    var index : Int
    
    init(index: Int) {
        self.index = index
    }
}

然后我有了一个控制焦点的文本字段的视图，我在这里添加了一条print语句来查看word.index==Focus！实际上从来都是真的.它确实变成了真的，但是设置isFocused没有影响，在打印期间它仍然是假的.

struct SolvedField: View {
    @State var word: WordEntry
    @FocusState var isFocused: Bool
    @Binding var focus: Int?
    var nextFocus: (Int) -> Void

    var body: some View {
        TextField("", text: $word.word)
            .onChange(of: focus, perform: { newValue in
                if(focus != nil){
                    self.isFocused = word.index == focus!
                    print("index \(word.index), focus \(focus!), isfocused: \(self.isFocused) should be focused \(word.index == focus!)")
                }
            })
            .focused(self.$isFocused)
            .submitLabel(.next)
            .onSubmit {
                isFocused = false
                self.nextFocus(word.index)
            }
    }
}

然后是包含单词条目列表的视图，这些单词条目随后被显示为文本字段控件.

    struct SolvedLettersLine: View {
        @State var words = [WordEntry(index: 0), WordEntry(index: 1), WordEntry(index: 2), WordEntry(index: 3)]
        @State var focus : Int?
        
        var body: some View {
            VStack(spacing:10){
                Group{
                    ForEach(words) { word in
                        SolvedField(word: word, focus: $focus, nextFocus:{
                            focus = $0 + 1
                        })
        

            }
        }
   }
}

不幸的是，我完全被困在如何让iOS将Textfield焦点切换到工作上，有人知道吗？