Using jQuery UI datepicker with WordPress custom post meta

if(is_admin()) {
wp_enqueue_script('jquery-ui-datepicker');
wp_enqueue_script('custom-js', get_template_directory_uri().'/js/custom-js.js');
wp_enqueue_style('jquery-ui-custom', get_template_directory_uri().'/css/jquery-ui-custom.css');
}
function my_admin_footer() {
?>
<script type="text/javascript">
jQuery(document).ready(function(){
jQuery('#registration_lastdate').datepicker({
dateFormat : 'd M yy'
});

jQuery('#training_date').datepicker({
dateFormat : 'd M yy'
});
});
</script>
<?php
}
add_action('admin_footer', 'my_admin_footer');

Custom page links without or with a list

$args = array(
'orderby' => 'post_title',
'order' => 'ASC',
'post_type' => 'page',
//'post_parent'=> '35',
'caller_get_posts' => 1
);
$pages = get_posts($args);
foreach($pages as $page) {
$out .= '<div class="bluecategory_wrapper">';
$out .= '<a href="'.get_permalink($page->ID).'" title="'.wptexturize($page->post_title).'">
<div class="bluecategory_left"></div><div class="bluecategory_bg">'.wptexturize($page->post_title).'</div>
<div class="bluecategory_right"></div></a></div>';
}
$out = $out;
echo $out;

Change WordPress “from” email header

By default, the default WordPress email adress looks like WordPress@yoursitename.com. Want to use your real email and username instead?

function res_fromemail($email) {
$wpfrom = get_option('admin_email');
return $wpfrom;
}
function res_fromname($email){
$wpfrom = get_option('blogname');
return $wpfrom;
}
add_filter('wp_mail_from', 'res_fromemail');
add_filter('wp_mail_from_name', 'res_fromname');

Sending users email on post publish

function send_email_publish_post($post_ID) 
{ global $wpdb; $permalink = get_permalink( $post_ID ); 
 $query = "SELECT * FROM {$wpdb->users}"; 
 $users = $wpdb->get_results( $query);
 foreach($users as $user) 
{ 
$permalink = get_permalink( $post_ID ); 
$message="A New Post published. You can view the post details from the link ".$permalink." This is an auto generated notification. Please do not reply to it."; 
wp_mail( $user->user_email, "A New Post published", $message); 
 } 
return $post_ID; 
} 
add_action('wp_publish_post','send_email_publish_post');

add theme support

add_theme_support( $feature );
$feature

• 'post-formats'
• 'post-thumbnails'
• 'custom-background'
• custom-header'
• 'automatic-feed-links'
• 'menus' 

Enabling Support for Post Thumbnails

add_theme_support( 'post-thumbnails' ); 

Default Usage 

if ( has_post_thumbnail() ) { the_post_thumbnail(); } 

Thumbnail Sizes 

the_post_thumbnail(); // without parameter -> Thumbnail the_post_thumbnail('thumbnail'); // Thumbnail (default 150px x 150px max) the_post_thumbnail('medium'); // Medium resolution (default 300px x 300px max) the_post_thumbnail('large'); // Large resolution (default 640px x 640px max) the_post_thumbnail( array(100,100) ); // Other resolutions 

Example of a new Post Thumbnail size named "category-thumb". 

add_image_size( 'category-thumb', 300, 9999 ); //300 pixels wide (and unlimited height)
Here is an example of how to use this new Post Thumbnail size in theme template files. the_post_thumbnail( 'category-thumb' );

Custom Backgrounds

add_theme_support( 'custom-background' ); 

Note that you can add default arguments using:
$defaults = array( 'default-color' => '', 
'default-image' => '', 
'wp-head-callback' => '_custom_background_cb', 
'admin-head-callback' => '', 'admin-preview-callback' => '' ); 

add_theme_support( 'custom-background', $defaults ); 

Example  
An example using default '#000000' background color with 'background.jpg' background image:

$args = array( 'default-color' => '000000',
 'default-image' => get_template_directory_uri() . '/images/background.jpg', ); 
add_theme_support( 'custom-background', $args );