SwiftUI:在创建 View 后动态更改 View 的过渡

Question

我想更改 View 的过渡 动态 创建 View 后。我切换状态变量 isTransition1通过单击按钮在 transition1 之间切换和 transition2如下。但是，如果这些过渡之一是不透明度，则它不会按预期工作。更改过渡后立即删除的 View 始终保持其原始过渡。令人惊讶的是，如果我改变 transition2滑动，它将毫无问题地工作。要删除的 View 将使用新的过渡。有什么办法可以使不透明度在这里起作用吗？

let transition1 = AnyTransition.asymmetric(insertion: .move(edge: .trailing),
                                           removal: .move(edge: .leading))

let transition2 = AnyTransition.opacity

struct Wrapper1<Content: View>: View {
  let content: Content

  var body: some View {
    content
  }
}

struct Wrapper2<Content: View>: View {
  let content: Content

  var body: some View {
    content
  }
}

struct TextView: View {
  let count: Int
  let color: Color

  var body: some View {
    ZStack {
      color
        .edgesIgnoringSafeArea(.all)
        .frame(maxWidth: UIScreen.main.bounds.width,
               maxHeight: UIScreen.main.bounds.height)

      Text("Count: \(count)")
        .font(.title)
        .offset(y: -200)
    }
  }
}

struct ContentView: View {
  @State private var count = 0
  @State private var isTransition1 = false

  var body: some View {
    ZStack {
      if count % 2 == 0 {
        Wrapper1(content: TextView(count: count, color: Color.green)
          .transition(isTransition1 ? transition1 : transition2))
        } else {
          Wrapper2(content: TextView(count: count, color: Color.red)
            .transition(isTransition1 ? transition1 : transition2))
        }

      HStack(spacing: 100) {
        Button(action: {
          self.isTransition1.toggle()
        }) {
          Text("Toggle Transition").font(.title)
        }

        Button(action: {
          withAnimation(.linear(duration: 2)) {
            self.count += 1
          }
        }) {
          Text("Increase").font(.title)
        }
      }
    }
  }
}

Answer 1

不确定我是否正确理解您尝试实现的效果，但尝试重置 View 层次结构(至少这肯定会重置过渡，因此它们不会相互影响):

  var body: some View {
    ZStack {
      if count % 2 == 0 {
        Wrapper1(content: TextView(count: count, color: Color.green)
          .transition(isTransition1 ? transition1 : transition2))
        } else {
          Wrapper2(content: TextView(count: count, color: Color.red)
            .transition(isTransition1 ? transition1 : transition2))
        }

      HStack(spacing: 100) {
        Button(action: {
          self.isTransition1.toggle()
        }) {
          Text("Toggle Transition").font(.title)
        }

        Button(action: {
          withAnimation(.linear(duration: 2)) {
            self.count += 1
          }
        }) {
          Text("Increase").font(.title)
        }
      }
    }.id(isTransition1)     // << here !!
  }