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我从网络.onAppear 异步加载项目，之后我的 ViewModel 强制重绘 swiftUI 视图。之后我需要滚动列表到特定项目。我这样做了.onRecieve，问题是视图重绘和滚动几乎同时执行，但据我所知，滚动确实先行，所以我需要添加丑陋的黑客延迟，而不是它工作正常。问题是有另一种方法如何在视图刷新后推迟滚动。

struct ItemsListView: View {
@Binding var selectedItem: Item?
@ObservedObject var viewModel: ViewModel
var body: some View {
    ScrollViewReader { proxy in
        List(viewModel.state.items) { item in
            let selected = item.id == selectedItem?.id
            self.createCell(item: item, selected: selected)
                .onTapGesture {
                    selectedItem = item
                }
        }
        .listStyle(SidebarListStyle())
        .navigationBarTitleDisplayMode(.inline)
        .onAppear {
            self.viewModel.trigger(.getItems) // triggers async load of items
        }
        .onReceive(viewModel.$state) { state in
            DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) { // hack to give a time redraw ItemsListView
                withAnimation {
                    proxy.scrollTo(selectedItem?.id, anchor: .center)
                }
            }
        }
}

}

查看模型代码，它是真实的，但对于这个主题有点简化

class ViewModel: ObservableObject {
    
    struct State {
        var items = [Item]()
    }
    
    enum Event {
        case getItems
    }
    
    func trigger(_ event: Event) {
        switch event {
        case .getItems: self.getItems()
        }
    }
    
    @Published var state = State()
    
    init(dataFetcher: RemoteDataProvider) {
        self.dataFetcher = dataFetcher
        super.init()
    }
    
    private func getItems() {
        dataFetcher.getItems()
            .sink { result in
                if case .failure(let err) = result {
                    print("Retrieving car items list failed:\(err)")
                }
            } receiveValue: {[weak self] items in
                self?.state.items = items
            }
            .store(in: &subscriptions)
    }
}
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