滚动视图中的ForEach直到交互才更新

问题描述

添加到数组中或从数组中删除时，除非用户与 ScrollView 进行交互，否则视图不会更新.

When adding to or removing from an array, the view does not update unless the user interacts with the ScrollView.

Model 是一个 ObservableObject ，它在应用程序生命周期的早期被声明为 StateObject ，然后作为 EnvironmentObject .

The Model is a ObservableObject that is declared as a StateObject early in the app lifecycle and then passed as a EnvironmentObject.

当添加到 store.profile！.tasks.append()或从视图中删除数据时，数据只是带有对象数组的自定义 Profile 对象除非用户滚动ScrollView，否则不会更新；我的意思是说1个像素.

The data is simply a custom Profile object with an array of objects, when adding to store.profile!.tasks.append() or removing from the view does not update unless the user scrolls the ScrollView; I mean literally by 1 pixel.

我尝试过的

• 在LazyVStack或VStack中包装ForEach
• 在VStack中包装NavigationLink
• 确保尺寸为全高，以防需要重新计算

代码

class Profile: Identifiable, Codable, Equatable
    var tasks: [Task]
}


struct Task: Identifiable, Codable, Equatable {
    var createdBy: String
    var title: String
    var date: Date
}

class Store : ObservableObject {
    @Published var profile: Profile?
}

struct ListView: View {

@EnvironmentObject var store: Store

  var body: some View {
     GeometryReader { geometry in
        ZStack(alignment: .bottomTrailing) {
          ScrollView(.vertical, showsIndicators: false){
              ForEach(store.profile!.tasks.filter({ return $0.createdBy == store.profile!.uid}).indices, id: \.self) { index in
                 NavigationLink(destination: DetailView().environmentObject(store)) {
                      TasksRow().id(UUID())
                 }
             }
          }
           .frame(maxWidth: geometry.size.width, alignment: .center)
           .frame(maxHeight: geometry.size.height)
           .background(Color.gray)
       }
    }
 }

推荐答案

您的 Profile 是引用类型，因此在其中添加任务时，对profile的引用不会更改，因此不会发布工作.

Your Profile is a reference type, so when you append task in it the reference to profile is not changed, so published does not work.

改为使用配置文件的值类型(即 struct )

Use instead value type for profile (ie. struct)

struct Profile: Identifiable, Codable, Equatable
    var tasks: [Task]
}

现在将任务附加到配置文件将更改配置文件本身，发布者发送事件和视图将刷新.

now appending task to profile will change profile itself, the publisher send event and view will refresh.

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