如何获取从服务获取的ViewModel列表中的数据，然后更新View？

Question

I have a MVVM question.

I am successfully gathering data, creating an IoC container in my VM and binding it to my view. The issue I am having is that the view doesnt update its UI unless i navigate somewhere and then go back. Then the list is populated. See my logic below:

Service:

public ObservableCollection<ClassData> _MyList;
public ObservableCollection<ClassData> MyList
{
    get
    {
        return _MyList;
    }
    private set
    {
        _MyList = value;
        RaisePropertyChanged("MyList");
    }
}

async Task LoadData()
{
    var top = await cloudService.GetData().ConfigureAwait(false);
    MyList = top.results;
}

public event PropertyChangedEventHandler PropertyChanged;
public void RaisePropertyChanged(string propName)
{
    if (PropertyChanged != null)
    {
        PropertyChanged(this, new PropertyChangedEventArgs(propName));
    }
}

Interface:

public ObservableCollection<ClassData> MyList { get; } 

VM (I do have a INotifyPropertyChanged in the VM as well, but do I need to use that in this example since its raisingpropertychanged from the service?):

 public ObservableCollection<ClassData> ViewModelList => this.service.MyList;

 private readonly IService service;
 public MyViewModel (IService service)
 {
   this.service = service;
 }

XAML:

<ListView ItemsSource = {Binding ViewModelList} ... >

Answer 1

Try something like this.

XAML:

<ListView ItemsSource="{Binding Service.MyList}" />

ViewModel

private IService _service;
public IService Service
{
   get => _service;
   set
   {
       _service = value;
       RaisePropertyChanged(nameof(Service));
       // So whenever _service is changed, it will generate an event.
       // UI will get Service.MyList.
   }
}

// No Observable collection.

2nd Solution.

// When _service is changed.
_service.PropertyChanged += Service_PropertyChanged;

// Manually raise event to update list.
private void Service_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
{
    if (e.PropertyName == "MyList")
        OnPropertyChanged(nameof(ViewModelList));
}