我试图在我的 .NET MAUI 应用程序中实现 StateContainer by Patrick McCurley 。 首次显示 ListView 时，它可以正常工作。 但是当状态再次改变时，ListView 不会显示，直到我滑动屏幕。

当我将任何视图元素（标签、按钮等）添加到包含 ListView 的视图时，它不会显示。但是当我将 StateContainer 与任何其他视图元素一起移动到 Grid 时，ListView 显示正确。如果 Grid 不包含 StateContainer 以外的其他元素，ListView 将无法正确显示。

我无法弄清楚这里有什么问题。带有其他视图元素的网格对我来说不是一个解决方案，因为我的页面不应该包含任何其他元素，比如 StateContainer。

这是一个重现该问题的示例：

附言我很抱歉有很多代码:) 我不知道问题出在哪里。

状态.cs

public enum States
{
    Loading, 
    Success
}

状态条件.cs

[ContentProperty(\"Content\")]
public class StateCondition : View
{
    public object State { get; set; }
    public View Content { get; set; }
}

状态容器.cs

[ContentProperty(\"Conditions\")]
public class StateContainer : ContentView
{
    public List Conditions { get; set; } = new();

    public static readonly BindableProperty StateProperty = 
        BindableProperty.Create(nameof(State), typeof(object), typeof(StateContainer), null, BindingMode.Default, null, StateChanged);

    private static void StateChanged(BindableObject bindable, object oldValue, object newValue)
    {
        var parent = bindable as StateContainer;
        if (parent != null)
            parent.ChooseStateProperty(newValue);
    }

    public object State
    {
        get { return GetValue(StateProperty); }
        set { SetValue(StateProperty, value); }
    }

    private void ChooseStateProperty(object newValue)
    {
        if (Conditions == null && Conditions?.Count == 0) return;

        var stateCondition = Conditions
            .FirstOrDefault(condition =>
                condition.State != null &&
                condition.State.ToString().Equals(newValue.ToString()));

        if (stateCondition == null) return;

        Content = stateCondition.Content;
    }
}

主页.xaml

MainPage.xaml.cs

public partial class MainPage : ContentPage
{
    private States _state;
    private int[] _someData;

    public MainPage()
    {
        InitializeComponent();
        this.BindingContext = this;

        SomeData = new[] { 1, 2, 3, 4, 5 };
        State = States.Success;

        // it can be executed from outside the page
        _ = Task.Run(ExecuteSomeWorkAsync);
    }

    public States State
    {
        get => _state;
        private set
        {
            if (_state != value)
            {
                _state = value;
                OnPropertyChanged();
            }
        }
    }
    public int[] SomeData
    {
        get => _someData;
        private set
        {
            if (_someData != value)
            {
                _someData = value;
                OnPropertyChanged();
            }
        }
    }

    public async Task ExecuteSomeWorkAsync()
    {
        await Task.Delay(2000);

        State = States.Loading;

        await Task.Delay(2000);

        // generate new data for displaying
        Random rnd = new();
        var data = Enumerable.Range(0, 5).Select(n => rnd.Next(0, 5)).ToArray();

        SomeData = data;
        State = States.Success;
    }
}