在SwiftUI中，如何设置已发布视图更改的动画？

我想设置视图更改的动画。
特别是，我做了一个视图，其中一个子视图是一个不断变化的视图

struct MasterView: View {

    @State var playerLeft: Bool = false
    @ObservedObject var viewModel: MasterViewModel

    var body: some View {
        ZStack {
            WaitPlayerBackView(isShowing: self.$playerLeft) {
                self.viewModel.currentView
            }
        }
    }
}

视图模型是一个ObservieObject类。currentView由从异步线程调用的方法更改，如下所示：

class MasterViewModel: ObservableObject {
    @Published var currentView: AnyView = AnyView(EmptyView())

    func changeView() {
        self.currentView = AnyView(NightView())
    }
}

它就像Android片段的副本（请原谅进行比较）。
如何设置此视图更改的动画？
我尝试过不同的选择，如：

self.viewModel.currentView.animate(.default)

或

但是，它们都不起作用。
这就是我在更改currentView实例时看到的转换。

---

将视图初始化移动到MasterView会使一切变得更简单：

struct MasterView: View {

    @State var playerLeft: Bool = false
    @ObservedObject var viewModel: MasterViewModel

    var body: some View {
        ZStack {
            VStack { //this represents WaitPlayerBackView
                if viewModel.day { //here are the posibles views that self.viewModel.currentView could have
                    Text("DayView").transition(AnyTransition.opacity.animation(.easeInOut(duration: 1.0)))
                } else {
                    Text("NightView").transition(AnyTransition.opacity.animation(.(duration: 1.0)))
                }
            }
        }
    }
}

class MasterViewModel: ObservableObject {
    @Published var day: Bool = false

    init () {
        _ = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(changeView), userInfo: nil, repeats: true) //Only for testing
    }
    @objc func changeView() { //@objc is only for testing
        day.toggle()
    }
}

---

此动画是否由您的

playerLeft

控制？否，playerLeft控制WaitPlayerBackView的可见性，WaitPlayerBackView是一个带有活动指示器的加载视图。我需要设置currentView的动画，它在运行时会发生变化。好的，这很有效，非常感谢！我想您在这里放错了两个括号：。transition（AnyTransition.opacity）。animation（（duration:1.0））。我放了一个索引而不是Bool，因为我有更多的视图可供选择。因此，我将currentView更改为Int。我还将.animation（.none）添加到所有不想设置动画的子视图中。

struct MasterView: View {

    @State var playerLeft: Bool = false
    @ObservedObject var viewModel: MasterViewModel

    var body: some View {
        ZStack {
            VStack { //this represents WaitPlayerBackView
                if viewModel.day { //here are the posibles views that self.viewModel.currentView could have
                    Text("DayView").transition(AnyTransition.opacity.animation(.easeInOut(duration: 1.0)))
                } else {
                    Text("NightView").transition(AnyTransition.opacity.animation(.(duration: 1.0)))
                }
            }
        }
    }
}

class MasterViewModel: ObservableObject {
    @Published var day: Bool = false

    init () {
        _ = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(changeView), userInfo: nil, repeats: true) //Only for testing
    }
    @objc func changeView() { //@objc is only for testing
        day.toggle()
    }
}