public void AddBroadcastHistory(BroadcastInfo info)
{
if (FindBroadcastHistroryItem(info)!=null) return;
var fav = BroadcastHistory.Where(i => i.Favorite);
var others = BroadcastHistory.Where(i => !i.Favorite);
BroadcastHistory = fav.Concat(Enumerable.Repeat(info, 1).Concat(others.Take(19))).ToArray();
}