Question

我制作了一个可以在Google Chrome中正常运行的API，然后创建了一个项目来存储数据和缓存，但是当我构建解决方案并使用Chrome运行API时，Android模拟器未显示任何数据，并且错误列表为0错误。有人帮我检查我的代码吗？我有5个班级，我认为可能有一些我找不到的错误。谢谢首先在数据文件夹 AppCache.cs

 public class AppCache
{
    IBlobCache Cache = null;

    public AppCache()
    {
        Cache = BlobCache.LocalMachine;
    }
   public event PropertyChangedEventHandler SessionsCacheChanged;
    public async Task GetAllSessionsAsync()
    {
        var cachedSessions = Cache.GetOrFetchObject<List<Session>>(
            "AllSessions",
            async () => await (new SessionManager()).FetchSessionsAsync(), DateTimeOffset.Now.AddHours(3)
            ).Subscribe((List<Session> obj) =>
            SessionsCacheChanged(obj, 
            new PropertyChangedEventArgs("SessionsCache"))
            );
    }
}

} 数据文件夹中的第二类 SessionManager.cs

public class SessionManager
{
    HttpClient client = new HttpClient();
    List<Session> ConferenceSessions = null;
    public async Task<List<Session>> FetchSessionsAsync()
    {
        string url = "http://192.168.56.1:45455/api/conferencesessions";
        try
        {
            var response = await client.GetAsync(url);
            if (response.IsSuccessStatusCode)
            {
                var content = await response.Content.ReadAsStringAsync();
                ConferenceSessions = JsonConvert.DeserializeObject<List<Session>>(content);

            }
        }
        catch (Exception ex)
        {
            Debug.WriteLine("@      ERROR{0}", ex.Message);
        }
        return ConferenceSessions;
    }
}

} 在ViewModel文件夹中。 SessionListViewModel.cs

  public class SessionListViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;
    private ObservableCollection<Session> _sessionslist;
    public ObservableCollection<Session> SessionList
    {
        get { return _sessionslist; }
        set
        {
            _sessionslist = value;
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("SessionsList"));
        }
    }
    public async Task FetchDataAsync()
    {
        var AppCache = new AppCache();
        AppCache.SessionsCacheChanged +=
            (sender, e) => { SessionList = new ObservableCollection<Session>((List<Session>)sender); };
        await AppCache.GetAllSessionsAsync();
    }
    public SessionListViewModel()
    {
        FetchDataAsync();
    }
}

}

数据库和缓存xamarin.form不在模拟器中存储数据

0 个答案: