lps/functions.php

<?php

/***********************************************************
######################### Admin ############################
************************************************************/

add_filter( 'show_admin_bar', '__return_false' );

add_action( 'admin_head-profile.php', 'lps24_remove_admin_color' );
function lps24_remove_admin_color() {
    remove_action( 'admin_color_scheme_picker', 'admin_color_scheme_picker' );
}

add_action( 'admin_bar_menu', 'lps24_remove_adminbar', 999 );
function lps24_remove_adminbar( $wp_admin_bar ) {
	$wp_admin_bar->remove_node('wp-logo');
  $wp_admin_bar->remove_node('updates');
  $wp_admin_bar->remove_menu('comments');
  $wp_admin_bar->remove_menu('customize');
  $wp_admin_bar->remove_menu('new-content');
	$wp_admin_bar->remove_menu('edit');
	$wp_admin_bar->remove_menu('new-user');
	$wp_admin_bar->remove_menu('new-post');
	$wp_admin_bar->remove_menu('new-page');
	$wp_admin_bar->remove_node('new-media');
  $wp_admin_bar->remove_node('view-site');
}

add_action( 'wp_dashboard_setup', 'lps24_disable_dashboard_items' );
function lps24_disable_dashboard_items() {
  remove_action('admin_notices', 'update_nag');
	remove_action('welcome_panel', 'wp_welcome_panel');
	remove_meta_box('dashboard_primary', 'dashboard', 'side');
	remove_meta_box('dashboard_secondary', 'dashboard', 'side');
	remove_meta_box('dashboard_quick_press', 'dashboard', 'side');
	remove_meta_box('dashboard_site_health', 'dashboard', 'normal');
	
}

/***********************************************************
####################### Comments ###########################
************************************************************/

add_action('admin_menu', function () {
	remove_menu_page('edit-comments.php');
});

add_filter('comments_open', '__return_false', 20, 2);
add_filter('pings_open', '__return_false', 20, 2);

add_action('admin_init','lps24_disable_comments');
function lps24_disable_comments() {
	$post_types = get_post_types();
	foreach ($post_types as $post_type) {
			if(post_type_supports($post_type,'comments')) {
					remove_post_type_support($post_type,'comments');
					remove_post_type_support($post_type,'trackbacks');
			}
	}
}

/***********************************************************
###################### Last Login ##########################
************************************************************/

add_action( 'wp_login', 'lps24_login_timestamp', 20, 2 );
function lps24_login_timestamp( $user_login, $user ) {
  update_user_meta( $user->ID, 'last_login', time() );
}
add_filter( 'manage_users_columns', 'lps24_user_last_login_column' );
function lps24_user_last_login_column( $columns ) {
  $columns['last_login'] = 'Last Login'; // column ID / column Title
  return $columns;
}
add_filter( 'manage_users_custom_column', 'lps24_last_login_column', 10, 3 );
function lps24_last_login_column( $output, $column_id, $user_id ){
	if( $column_id == 'last_login' ) {
    $last_login = get_user_meta( $user_id, 'last_login', true );
    $date_format = 'j M, Y';
    $output = $last_login ? date( $date_format, $last_login ) : '-';
	}
	return $output;
}
add_filter( 'manage_users_sortable_columns', 'lps24_sortable_columns' );
function lps24_sortable_columns( $columns ) {
	return wp_parse_args( array(
	 	'last_login' => 'last_login'
	), $columns );
}
add_action( 'pre_get_users', 'lps24_sort_last_login_column' );
function lps24_sort_last_login_column( $query ) {
	if( !is_admin() ) { return; }
  $orderby = $query->get('orderby');
	if( 'last_login' == $orderby ) {
    $query->set('meta_key','last_login');
    $query->set('orderby','meta_value');
	}
	return $query;
}