Question

我确定我做错了什么，但我不知道什么。

我有一个小列表，我用计时器更新文本，我可以在调试器中看到更新的内容。但是列表不会更新...

谢谢您的帮助。

struct ListTest: View {

    @State      var texts       : [String]

    var body: some View {
        List {
            ForEach(self.texts, id: \.self) { text in
                Text(text)
            }
        }
    }
}

struct ContentView: View {

    @State var texts = ["a"]

    var body: some View {

        ListTest(texts: self.texts)
            .onAppear() {
                Timer.scheduledTimer(withTimeInterval: 0.5, repeats: true) { (timer) in
                    self.texts.append("\(self.texts.count)")
                    print(self.texts)
                }
        }
    }
}

Answer 1

从您的ListTest中删除@State属性包装器

struct ListTest: View {
    var texts       : [String]
    var body: some View {
        List {
            ForEach(self.texts, id: \.self) { text in
                Text(text)
            }
        }
    }
}

最后，考虑更多的“可兼容组合”代码

import SwiftUI
struct ListTest: View {
    var texts: [String]
    var body: some View {
        List {
            ForEach(self.texts, id: \.self) { text in
                Text(text)
            }
        }
    }
}

struct ContentView: View {
    @State var texts = ["a"]
    let tp = Timer.publish(every: 0.5, on: .main, in: .default).autoconnect()
    var body: some View {
        ListTest(texts: self.texts)
            .onReceive(tp) { (date) in
            self.texts.append("\(self.texts.count)")
        }
    }
}
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

在功能上相等

文本更改后列表未更新

1 个答案: