SwiftUI:在列表滚动中动态移动navigationBar项

import SwiftUI

struct ContentView: View {
    @State private var offset: CGFloat = 0
    
    var body: some View {
        NavigationView {
            ScrollView {
                GeometryReader { geometry in
                    VStack {
                        ForEach(0..<100) { index in
                            Text("Item \(index)")
                                .padding()
                        }
                    }
                    .onAppear {
                        self.offset = geometry.frame(in: .global).minY
                    }
                    .navigationBarTitle("Title")
                    .navigationBarItems(trailing: Button(action: {
                        // 按钮操作
                    }) {
                        Image(systemName: "plus")
                    })
                    .background(Color.white)
                    .offset(y: -self.offset)
                    .edgesIgnoringSafeArea(.top)
                }
            }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}