更改日期时，SwiftUI DatePicker会在短日期格式和中日期格式之间切换

import SwiftUI

struct ContentView: View {
    @State private var selectedDate = Date()
    @State private var isShortFormat = true
    
    var body: some View {
        VStack {
            DatePicker(
                "Select a date",
                selection: $selectedDate,
                displayedComponents: .date
            )
            .datePickerStyle(.graphical)
            .labelsHidden()
            
            Button(action: {
                isShortFormat.toggle()
            }) {
                Text(isShortFormat ? "Switch to Medium Format" : "Switch to Short Format")
                    .padding()
                    .background(Color.blue)
                    .foregroundColor(.white)
                    .cornerRadius(10)
            }
        }
        .padding()
    }
}

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