c# - 我更新了 ObservableCollection 列表，但 UI 没有从标签页更新问题

Question

我更新了 ObservableCollection 列表，但 UI 没有从选项卡页面更新我也清除列表然后分配新列表，列表的值发生变化但 UI 没有更新

public ObservableCollection<Dashboard> DetailsList { get; set; } = new ObservableCollection<Dashboard>();
    //API Call
    details = await _clientAPI.getDashboardDetails(id);
    if (details != null)
    {
        DetailsList.Clear();
        foreach (var item in details)
        {
            DetailsList.Add(item);
        }
    }

标签： c#xamarinxamarin.formsobservablecollection

Answer 1

我认为您错过了绑定上下文。添加下面的代码。

  this.BindingContext = this;

我制作了一个代码示例供您参考。我不确定你的模型是什么，我用一个简单的模型来测试。

Page1.xaml.cs

 public partial class Page1 : ContentPage
{
    public ObservableCollection<Dashboard> DetailsList { get; set; }
    public Page1()
    {
        InitializeComponent();

        DetailsList = new ObservableCollection<Dashboard>()
        {
            new Dashboard(){ Name="AA", Country="CountryA"},
            new Dashboard(){ Name="BB", Country="CountryB"},

        };
        this.BindingContext = this;

    }

    private void btnUpdate_Clicked(object sender, EventArgs e)
    {
        List<Dashboard> details = new List<Dashboard>();
        details.Add(new Dashboard() { Name = "CC", Country = "CountryC" });
        details.Add(new Dashboard() { Name = "DD", Country = "CountryD" });

        if (details != null)
        {
            DetailsList.Clear();
            foreach (var item in details)
            {
                DetailsList.Add(item);
            }
        }
    }
}
public class Dashboard
{
    public string Name { get; set; }
    public string Country { get; set; }

}

xml:

   <ContentPage.Content>
    <StackLayout>
        <Button
            x:Name="btnUpdate"
            Clicked="btnUpdate_Clicked"
            Text="Update" />
        <ListView ItemsSource="{Binding DetailsList}">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <ViewCell>
                        <StackLayout Orientation="Horizontal">
                            <Label Text="{Binding Name}" />
                            <Label Text="{Binding Country}" />
                        </StackLayout>
                    </ViewCell>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>
    </StackLayout>
</ContentPage.Content>

更新：