private bool AuthorFilter(object item)
        {
            IKanbanModel task   = item as IKanbanModel;
            bool         result = false;

            if (FilterString.Equals(""))
            {
                result = true;
            }
            else
            {
                result = (task.ImageURL.ToString().Contains(FilterString));
            }

            return(result);
        }
        private bool TagFilter(object item)
        {
            IKanbanModel task   = item as IKanbanModel;
            bool         result = false;

            if (FilterString.Equals(""))
            {
                result = true;
            }
            else
            {
                foreach (string s in task.Tags)
                {
                    if (s.Contains(FilterString))
                    {
                        result = true;
                        break;
                    }
                }
            }

            return(result);
        }