class BP_Custom_User_Ids {

    private $custom_ids = array();

    public function __construct() {

        $this->custom_ids = $this->get_custom_ids();

        add_action( 'bp_pre_user_query_construct',  array( $this, 'custom_members_query' ), 1, 1 );
        add_filter( 'bp_get_total_member_count',    array( $this, 'custom_members_count' ), 1, 1 );

    }

private function get_custom_ids() {
    global $wpdb;

    //figure out if the logged-in user is male or female
   $sex = xprofile_get_field_data( 852, bp_loggedin_user_id() );

   if ( $sex == 'Muslim' )
      $query = "SELECT user_id FROM {$wpdb->prefix}bp_xprofile_data WHERE field_id = 852 AND value = 'Muslima'";
   else
      $query = "SELECT user_id FROM {$wpdb->prefix}bp_xprofile_data WHERE field_id = 852 AND value = 'Muslim'";


    $custom_ids = $wpdb->get_col( $query );


    return $custom_ids;
}

    function custom_members_query( $query_array ) {

        $query_array->query_vars['include'] = $this->custom_ids;

    }

    function custom_members_count ( $count ) {

        $new_count = count( $this->custom_ids );
        return $new_count;

    }
}

function custom_user_ids( ) {

    new BP_Custom_User_Ids ();

}

add_action( 'bp_before_directory_members', 'custom_user_ids' );