如何在SwiftUI中将视图添加到层次结构时为过渡设置动画

import SwiftUI

struct ContentView: View {
    @State private var isShowingView = false
    
    var body: some View {
        VStack {
            Button("添加视图") {
                withAnimation {
                    isShowingView.toggle()
                }
            }
            
            if isShowingView {
                Rectangle()
                    .fill(Color.blue)
                    .frame(width: 200, height: 200)
                    .transition(.scale) // 设置过渡效果
            }
        }
    }
}

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