弹出屏幕的动画不起作用 SwiftUI

Question

我试图在按下按钮时弹出一个屏幕，然后在按下按钮或弹出屏幕上的“X”时消失。

下面的代码工作正常，除了我想要动画并且动画不起作用，弹出窗口只是出现和消失。这是怎么回事？

import SwiftUI

struct PopUpViewToggle: View {
    
    @State var show: Bool = false
    @State var offset: CGFloat = UIScreen.main.bounds.height
    
    var body: some View {
        ZStack {
            Button("Button") {
                show.toggle()
                offset = show ? UIScreen.main.bounds.height / 2 : UIScreen.main.bounds.height
            }
            if show {
                ScreenToggle(show: $show, offset: $offset)
                    .offset(y: offset)
                    .animation(.spring(), value: offset)
            }
        }
    }
}

struct ScreenToggle: View {
    
    @Binding var show: Bool
    @Binding var offset: CGFloat
    
    var body: some View {
        ZStack {
            RoundedRectangle(cornerRadius: 20)
                
            VStack {
                HStack {
                    Button {
                        show.toggle()
                        offset = show ? UIScreen.main.bounds.height / 2 : UIScreen.main.bounds.height
                    } label: { Image(systemName: "x.circle.fill").font(.largeTitle) }

                    Spacer()
                }
                .padding()
                Spacer()
            }
        }
    }
}

Answer 1

将show.toggle() 放入 withAnimation 块中。

Button("Button") {
  offset = show ? UIScreen.main.bounds.height / 2 : UIScreen.main.bounds.height
  withAnimation {
    show.toggle()
  }
}