/// <summary>
        /// Loads the groups.
        /// </summary>
        private void LoadDropDowns()
        {
            var parts = ( GetAttributeValue( "GroupFilter" ) ?? string.Empty ).Split( '|' );
            Guid? groupTypeGuid = null;
            Guid? rootGroupGuid = null;
            if ( parts.Length >= 1 )
            {
                groupTypeGuid = parts[0].AsGuidOrNull();
                if ( parts.Length >= 2 )
                {
                    rootGroupGuid = parts[1].AsGuidOrNull();
                }
            }

            var groupService = new GroupService( new RockContext() );

            string defaultGroupPublicKey = string.Empty;
            var contextCookie = Request.Cookies["Rock:context"];
            if ( contextCookie != null )
            {
                var cookieValue = contextCookie.Values[typeof( Rock.Model.Group ).FullName];

                string contextItem = Rock.Security.Encryption.DecryptString( cookieValue );
                string[] contextItemParts = contextItem.Split( '|' );
                if ( contextItemParts.Length == 2 )
                {
                    defaultGroupPublicKey = contextItemParts[1];
                }
            }

            var defaultGroup = groupService.GetByPublicKey( defaultGroupPublicKey );

            IQueryable<Group> qryGroups = null;

            // if rootGroup is set, use that as the filter.  Otherwise, use GroupType as the filter
            if ( rootGroupGuid.HasValue )
            {
                var rootGroup = groupService.Get( rootGroupGuid.Value );
                if ( rootGroup != null )
                {
                    qryGroups = groupService.GetAllDescendents( rootGroup.Id ).AsQueryable();
                }
            }
            else if ( groupTypeGuid.HasValue )
            {
                qryGroups = groupService.Queryable().Where( a => a.GroupType.Guid == groupTypeGuid.Value );
            }

            if ( qryGroups == null )
            {
                nbSelectGroupTypeWarning.Visible = true;
                ddlGroup.Visible = false;
            }
            else
            {
                nbSelectGroupTypeWarning.Visible = false;
                ddlGroup.Visible = true;
                ddlGroup.Items.Clear();
                var groups = qryGroups.OrderBy( a => a.Order ).ThenBy( a => a.Name ).ToList();
                foreach ( var group in groups )
                {
                    var listItem = new ListItem( group.Name, HttpUtility.UrlDecode( group.ContextKey ) );
                    if ( defaultGroup != null )
                    {
                        listItem.Selected = group.Guid == defaultGroup.Guid;
                    }

                    ddlGroup.Items.Add( listItem );
                }
            }
        }