ios - 如何在 SwiftUI 中禁用位置动画？

Question

我想以VStack编程方式滚动一个子视图，并且一些子视图可以独立设置动画，但是当更改VStack' 偏移时，动画子视图移动到动画的最终位置，这不是我想要的，如何禁用动画这个位置变化？这是我的演示代码，

import SwiftUI

struct ContentView: View {
    @State var angle:Double = 0
    @State var offset = 0
    var body: some View {
            LazyVStack {
                ForEach((0..<100)) { i in
                    if i == 25 {
                        Rectangle()
                            .frame(width: 30, height: 30)
                            .animation(.none)
                            .rotationEffect(.degrees(angle), anchor: .center)
                            .animation(Animation.linear(duration: 3).repeatForever(autoreverses: false))
                            .onAppear {
                                angle = 360
                            }
                    } else {
                        Text("number \(i)")
                    }
                }
            }
            .offset(y: CGFloat(offset))
            .animation(.none)
            .onAppear {
                offset = 200
            }
        
    }
}

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

和效果，

Answer 1

尝试以下方法（在 Xcode 12.0.1、iOS14 中测试）：

设置时使用显式动画调用angle：

import SwiftUI

struct ContentView: View {
    @State var angle:Double = 0
    @State var offset = 0
    var body: some View {
        LazyVStack {
            ForEach((0..<100)) { i in
                if i == 25 {
                    Rectangle()
                        .frame(width: 30, height: 30)
                        .rotationEffect(.degrees(angle), anchor: .center)
                        .onAppear {
                            withAnimation(Animation.linear(duration: 3).repeatForever(autoreverses: false)) {
                                angle = 360
                            }
                        }
                } else {
                    Text("number \(i)")
                }
            }
        }
        .offset(y: CGFloat(offset))
        .onAppear {
            offset = 200
        }
        
    }
}