Simple functions.php theme file for WordPress custom themes

WordPress Function.php

<?php 

// Define and creating constants
define('TEMPPATH', get_bloginfo('stylesheet_directory')); // Path to the theme directory
define('IMAGES', TEMPPATH. "/images"); // IMAGES uses TEMPPATH and appends the image folder

// Add theme support for custom menu
add_theme_support('nav-menus');
if(function_exists('register_nav_menu')) {
	// This theme uses wp_nav_menu() in one location.
	register_nav_menu( 'primary-menu', __('Primary Menu'));
}

// Add WALKER custom class to menu
function add_anchor_to_nav($menu) {
  remove_filter('wp_nav_menu_items', 'add_anchor_to_nav', 10, 2);
  $pat = '(<nav[^>]+?>)(.*)';
  $menu = preg_replace('|'.$pat.'|','$1<a href="#" class="close">X</a>$2', $menu);
  
  return $menu;
}
add_filter('wp_nav_menu', 'add_anchor_to_nav', 10, 2);


// Add sidebar support
if(function_exists('register_sidebar')) { 
	register_sidebar( array(
		'name' => __('Sidebar', 'sidebar'),
		'id' => 'widget-area',
		'description' => __('The widget area', 'dir'),
		'before_widget' => '<li class="grid_4 widget">',
		'after_widget' => '</li>',
		'before_title' => '<h2>',
		'after_title' => '</h2>',
	));
	
}


// Add featured image support
if(function_exists('add_theme_support')) {
	add_theme_support('post-thumbnails');
	set_post_thumbnail_size(260, 150);
	add_image_size('thumbnail-post', 300, 0, true); // Post thumbnails
	add_image_size('thumbnail-archive', 680, 180, true); // Archive thumbnails
	add_image_size('thumbnail-pages', 300, 0, true); // Pages thumbnails
}


require_once('wp-theme-options/theme-settings.php');

?>