private ObservableCollection <TreeItemViewModel> GeTreeViewItems(bool isUniqueCheckins)
{
ObservableCollection <TreeItemViewModel> treeViewItems = new ObservableCollection <TreeItemViewModel>();
List <Checkin> checkins = untappdService.GetCheckins(isUniqueCheckins);
for (int i = 0; i < checkins.Count; i++)
{
Checkin checkin = checkins[i];
treeViewItems.Add(new TreeItemViewModel(checkin.Id, untappdService.GetTreeViewCheckinDisplayName(checkin, i + 1)));
}
return(treeViewItems);
}