C# 无法使用可观察集合绑定到列表视图

C# can't binding to list view using observable collection

当我尝试将可观察类型的集合绑定到 listView 时遇到问题。 我确定集合正在正确更新,但列表视图中没有任何反应。

我正在检索 JSON 个对象并将它们转换为 Observable 的集合。

public partial class MainWindow : Window
{
    public ObservableCollection<post> mproducts = new ObservableCollection<post>();

    public MainWindow()
    {

        InitializeComponent();
        DataContext = mproducts;
    }
    private static readonly HttpClient Client = new HttpClient();
    async void OnLoad(object sender, RoutedEventArgs e)
    {
        HttpResponseMessage response = await Client.GetAsync("https://jsonplaceholder.typicode.com/posts");
        response.EnsureSuccessStatusCode();
        string data = await response.Content.ReadAsStringAsync();

        mproducts = JsonConvert.DeserializeObject<ObservableCollection<post>>(data);
        MessageBox.Show(mproducts.Count.ToString());

    }
    public class post
    {
        public string UserId { get; set; }
        public string Id { get; set; }
        public string Title { get; set; }
        public string Body { get; set; }
    }

}

这是XAML class:

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Loaded="OnLoad"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
    
        <ListView x:Name="products" Margin="400,0,0,0" Width="600" SelectionChanged="ListView_SelectionChanged" ItemsSource="{Binding mproducts}"; >
           
           
            <ListView.View>
                <GridView>
                    <GridViewColumn Width="160" Header="Description" DisplayMemberBinding="{Binding UserId}"/>
                    <GridViewColumn Width="160" Header="Date Filed" DisplayMemberBinding="{Binding Id}"/>
                    <GridViewColumn Width="160" Header="Filed By" DisplayMemberBinding="{Binding Title}"/>
                    <GridViewColumn Width="150" Header="Page" DisplayMemberBinding="{Binding Body}"/>
                    <GridViewColumn Width="Auto" Header="" />
                </GridView>
            </ListView.View>
        </ListView>
    </Grid>


</Window>

当应用程序加载时,它会在消息框中显示数字 100,这意味着集合已更新。

ListBox 的绑定应该如下所示

ItemsSource="{Binding}"

因为您要绑定到存储在 DataContext 中的集合本身。同样在您的代码中,您应该在 OnLoad 事件中执行 DataContext = mproducts; 之后,您将集合分配给 mproducts,如下所示:

mproducts = JsonConvert.DeserializeObject<ObservableCollection<post>>(data);
DataContext = mproducts;