Update Live Tile By setting poll URLs C#

Question

I have developed an application on visual studio 2013 for windows 8.1 . I have % URLs for which i want to create live tiles . There is o function in app.xaml.cs where you can define poll URLs but i dont know how to do that. Can anyone help me please? Thanks in advance. The code goes like this for setting poll URLs

 public static void SetPollUrls(params string[] _pollUrls)
    {
        urisToPoll = new List<Uri>();

        foreach(string url in _pollUrls)
        {
            if (string.IsNullOrEmpty(url))
                continue;
            try
            {
                urisToPoll.Add(new Uri(url));
            }
            catch (Exception)
            {
                // The URLs need to be well formed. 
            }
        }
    }