public MainViewModel()
      {
         Players = new ObservableCollection<PlayersViewModel>();
 
         string url = "http://192.168.1.19/projects/t20lite/index.php/api/api/get_playersbyteam;
         var task = new HttpGetTask<PlayerList>(url, this.OnPostExecute);
         task.OnPreExecute = this.OnPreExecute;
         task.OnError = this.OnError;
 
         task.Execute();
      }   
    public void GetPlayer()
    {
        string url = "http://192.168.1.19/projects/t20lite/index.php/api/api/get_playersbyteam;"
                     // Do something with url and tour TeamID
                     var task = new HttpGetTask <PlayerList>(url, this.OnPostExecute);

        task.OnPreExecute = this.OnPreExecute;
        task.OnError      = this.OnError;

        task.Execute();
    }