SwiftUI串列視圖不反映洗掉正確的視圖模型物件？

我正在創建一個功能，用戶可以在從我們的 API 中洗掉帖子后從陣列中洗掉它，我能夠成功地從陣列中洗掉正確的帖子，但我的 NewsFeed 視圖總是從視圖中洗掉錯誤的 PostCell，即使是正確的物件正在從陣列中洗掉？？？

NewsFeed 視圖似乎洗掉了串列中的最后一個 PostCell，而不是從陣列中成功洗掉的物件？

我正在通過列印出所有物件ID來檢查是否從視圖模型中洗掉了正確的物件，并且它肯定已經消失了。但是，Newsfeed 視圖洗掉了一個完全不同的視圖（最后一個），并且仍然顯示應該洗掉的視圖？

知道為什么會這樣嗎？

顯示所有帖子的新聞源視圖

struct NewsFeed: View {
    @StateObject var newsfeedVM = NewsFeedViewModel()

    var body: some View {
        NavigationView {
            List(0..<newsfeedVM.posts.count, id: \.self) { index in
               PostCell(post: newsfeedVM.posts[index] )
            }
        }
    }
}

查看模型

class NewsFeedViewModel: ObservableObject {
    @Published var posts: [Post] = []
           
    var subscriptions = Set<AnyCancellable>()

    static let removePostFromArray = PassthroughSubject<String, Never>()
    
    init() {
        Self.removePostFromArray.sink { postId in
            print(postId)
            if let index = self.posts.firstIndex(where: { $0.id == postId }) {
                 // removes correct object
                self.posts.remove(at: index)
                 // confirms correct object was removed
                self.posts.forEach { post in
                    print(post.id)
                }
            }
        }.store(in: &subscriptions)
    }
}

每個帖子單元格都有一個用于洗掉帖子的操作表。

struct PostCell: View {
    @StateObject var postVM = PostViewModel()
    @State var post: Post
    @State var showActionSheet: Bool = false

    var body: some View {
        VStack(spacing: 5) {
            PostMedia(post: $post)
        }
        .actionSheet(isPresented: $showActionSheet) { "REPORT POST" }
    }

    // remove post with Combine
    func reportPost(post: Post) {
        NewsFeedViewModel.removePostFromArray.send(report.postId)
    }
}

uj5u.com熱心網友回復：

這可以在沒有靜態成員和組合的情況下解決。我會向每個用戶傳遞一個閉包，PostCell這是用戶洗掉/報告帖子時執行的操作：

struct NewsFeed: View {
    @StateObject var newsfeedVM = NewsFeedViewModel()

    var body: some View {
        NavigationView {
            List(newsfeedVM.posts, id: \.id) { post in
               PostCell(post: post, removePost: {vm.removePost(post.id)} ) // use the ID not the index
            }
        }
    }
}

class NewsFeedViewModel: ObservableObject {
    @Published var posts: [Post] = []
           
    // var subscriptions = Set<AnyCancellable>()

    // none of the static stuff: static let removePostFromArray = PassthroughSubject<String, Never>()
    
    func removePost(id: Int) {
        posts.removeAll(where: {$0.id == id})
    }
}

struct PostCell: View {
    @StateObject var postVM = PostViewModel()
    @State var post: Post
    @State var showActionSheet: Bool = false
    var removePost: func () -> ()

    var body: some View {
        VStack(spacing: 5) {
            PostMedia(post: $post)
        }
        .actionSheet(isPresented: $showActionSheet) { "REPORT POST" } // call report() here
    }

    // use a closure instead
    func report() {
        // not this: NewsFeedViewModel.removePostFromArray.send(report.postId)
        removePost()
    }
}

edit: if you want to have access to index, you can pass an array of tuples (index, item) to List (only tested this with ForEach. should work though):

List(Array(newsfeedVM.posts.enumerated()), id: \.index) { index, item in
    // ... now you have both index and item. you use item to draw the views
}

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