我正在尝试了解如何知道用户何时点击了使用.searchable修饰符的iOS应用程序中的搜索字段。苹果文档称，用户可以通过获取Environment值来了解用户何时与由searchable（text：placement：prompt：）等可搜索修饰符生成的搜索字段交互
然而，这第一个代码不起作用。文本总是说不搜索。我一定错过了一些基本的东西：

struct ContentView: View {
    @Environment(\.isSearching) var isSearching
    @State private var searchText: String = ""

    var items = ["One", "Two", "Three", "Four", "Five"]

    var body: some View {
        NavigationStack {
            VStack {
                Text(isSearching ? "Searching" : "Not Searching")
                List {
                    ForEach(searchResults, id: \.self) { item in
                        Text(item)
                    }
                }
                .listStyle(PlainListStyle())
                .searchable(text: $searchText)
            }//v
            .padding()
        }//nav
    }//body

    private var searchResults: [String] {
        if searchText.isEmpty {
            return items
        } else {
            return items.filter({ item in
                item.contains(searchText)
            })
        }
    }//var search results

}//struct

但是，如果我将大部分代码提取到另一个视图，这确实有效：

struct ContentView2: View {
    @State private var searchText: String = ""

    var body: some View {
        NavigationStack {
            SearchedView2 (searchText: $searchText)
                .searchable(text: $searchText)
        }//nav
    }//body

}//struct

struct SearchedView2: View {
    @Environment(\.isSearching) var isSearching

    @Binding var searchText: String
    var items = ["One", "Two", "Three", "Four", "Five"]

    var body: some View {
        VStack {
            Text(isSearching ? "Searching" : "Not Searching")
            List {
                ForEach(searchResults, id: \.self) { item in
                    Text(item)
                }
            }
            .listStyle(PlainListStyle())
        }//v
        .padding()
    }//body

    private var searchResults: [String] {
        if searchText.isEmpty {
            return items
        } else {
            return items.filter({ item in
                item.contains(searchText)
            })
        }
    }//var search results
}//struct

我很困惑。为什么第一段代码不起作用？欢迎提供指导。Xcode 14.0.1 iOS 16.0