using System;

using System.Collections.Generic;

using System.Threading.Tasks;

public class Program

{

    public static void Main()

    {

        Task.Run(() =>

                 {

                     // fetchesLeagueData (represented by the list of strings below as leagueIds)

                     List<string> leagues = new List<string>()

                            {

                                "league1",

                                "league2",

                                "league3",

                                "league4",

                                "league5",

                                "league6",

                                "league7",

                                "league8",

                                "league9",

                                "league10",

                                "string11",

                                "string12",

                                "string13",

                                "string14",

                                "string15",

                                "string16",

                                "string17",

                                "string18",

                                "string19",

                                "string20"

                            };

                     // for each leagueId fetch leagues from Json represented by the foreach below...

                     Parallel.ForEach<string>(leagues, (leagueId) =>

                     {

                         List<string> matches = new List<string>()

                            {

                                "match1",

                                "match2",

                                "match3"

                            };

                         foreach (var match in matches)

                         {

                             // push match to observable (possibly on UI thread invoke required)

                             Console.WriteLine(string.Format("{0} - {1}", leagueId, match));

                         }

                         // re-sort list on UI thread each time one loads may be required???

                     });

                     // Hide spinny waiting :)

                 });

        // Show spinny waiting.

        Console.WriteLine("Hello World");

    }

}