C# Can't add items to observable collection

Question

I have a problem where im trying to add my items to my observable collection, but i get this error:

Argument 1: cannot convert from 'System.Collections.Generic.List' to 'GameFinder.GetGamesList'

code:

private void RequestCompleted(object sender, DownloadStringCompletedEventArgs e)
    {

        if (e.Error == null)
        {
            var feedXml = XDocument.Parse(e.Result);

            var gameData = feedXml.Root.Elements("Game").Select(x => new GetGamesList
            {
                ID = (int)x.Element("id"),
                GameTitle = (string)x.Element("GameTitle"),
                ReleaseDate = (string)x.Element("ReleaseDate"),
                Platform = (string)x.Element("Platform")
            })
              .ToList();
            Items.Add(gameData); // THE ERROR IS HERE - Items is the observablecollection
        }
    }

private ObservableCollection<GetGamesList> _Items = new ObservableCollection<GetGamesList>();
    public ObservableCollection<GetGamesList> Items
    {
        get
        {
            return this._Items;
        }
    }

public class GetGamesList
{
    public int ID { get; set; }
    public string GameTitle { get; set; }
    public string ReleaseDate { get; set; }
    public string Platform { get; set; }
}

Answer 1

Try

foreach (var item in gameData) Items.Add(item)

gameData is a List<GetGamesList> so you need to add each item from gameData into Items list and since ObservableCollection doesn't have AddRange you'll need to do it manually in the loop

Answer 2

What exactly don't you understand on cannot convert from 'System.Collections.Generic.List' to 'GameFinder.GetGamesList'? Add method accepts single element, whereas you are passing in a list of elements. You can use new ObservableCollection<GetGamesList>(gameData). And remove the ToList statement at the end of you Linq query.