tahirtaous

// Remove 2012 default sidebar widgets from admin area
// http://codex.wordpress.org/Function_Reference/unregister_sidebar
// following code will remove/unregister 2012 sidebars from admin area
// you can unregister any sidebar just replave sidebar-1 sidebar-2 and sidebar-3 with your sidebar id. you can find  sidebar id's 
// in parent theme's functions.php file
// http://codex.wordpress.org/Function_Reference/unregister_sidebar for more details
function remove_some_widgets(){

	// Unregister some of the TwentyTen sidebars
	unregister_sidebar( 'sidebar-1' );

tahirtaous

// CUSTOM ADMIN MENU LINK FOR ALL SETTINGS Under Setting Menu 
   function all_settings_link() {
    add_options_page(__('All Settings'), __('All Settings'), 'administrator', 'options.php');
   }
   add_action('admin_menu', 'all_settings_link');

tahirtaous

<!-- add this code in page.php to display Next page and Previous page link below pages in WordPress
this will display next and previous page link not next previous post link
http://codex.wordpress.org/Next_and_Previous_Links#The_Next_and_Previous_Pages -->

<?php
	$pagelist = get_pages('sort_column=menu_order&sort_order=asc');
	$pages = array();
	foreach ($pagelist as $page) {
	   $pages[] += $page->ID;
	}

tahirtaous

// Open you functions.php file and paste the following code:
// Save the file and open your blog homepage to run the code. Once done, there’s no need to keep the code snippet in your
// functions.php file, as it will always delete all post revisions. So simply remove it.
// http://www.wprecipes.com/easily-delete-wordpress-post-revisions-using-your-fuctions-php-file


$wpdb->query( "
DELETE FROM $wpdb->posts
WHERE post_type = 'revision'
" );

tahirtaous

// Source : http://wordpress.stackexchange.com/questions/1567/best-collection-of-code-for-your-functions-php-file
// unregister all default WP Widgets
function unregister_default_wp_widgets() {
    unregister_widget('WP_Widget_Pages');
    unregister_widget('WP_Widget_Calendar');
    unregister_widget('WP_Widget_Archives');
    unregister_widget('WP_Widget_Links');
    unregister_widget('WP_Widget_Meta');
    unregister_widget('WP_Widget_Search');
    unregister_widget('WP_Widget_Text');

tahirtaous

// Wordpress Custom Admin Footer
// customize admin footer text. Add this to functions.php
// Source http://wordpress.stackexchange.com/posts/6005/revisions
// Modified by Tahir Taous


// customize admin footer text Will be visible in Dashboard
function custom_admin_footer() {
        echo 'Created By <a href="//tahirtaous.com/contact">Tahir Taous</a> ';
} 

tahirtaous

// Source http://wordpress.stackexchange.com/posts/28530/revisions
// Tested and worked on WordPress 4.1 Beta
//REMOVE VERSION STRING FROM HEADER
remove_action('wp_head', 'wp_generator');

//HIDE LOGIN ERROR MESSAGES (Wrong Password, No Such User etc.)
add_filter('login_errors',create_function('$a', "return null;"));

// Remove admin name in comments class
// Source: http://www.wprecipes.com/wordpress-hack-remove-admin-name-in-comments-class

tahirtaous

// Reference : https://www.cms2cms.com/blog/6-useful-yet-relatively-unknown-wordpress-functions/
// add this code to sidebar.php or anywhere you want to display email addess
// remove <?php and ?> if you are going to paste this in functions.php
// Tested WordPress 4.1 Jan 25 2015

<?php 

$email = 'mymail@mail.com';
echo 'You can contact me at ' . antispambot( $email ) . ' any time';

tahirtaous

// Source: https://www.cms2cms.com/blog/6-useful-yet-relatively-unknown-wordpress-functions/
// This function will generate something like this
// This post was published 2 weeks ago
// Tested : WordPress 4.1
<?php 
echo 'This post was published ' . human_time_diff( get_the_time( 'U' ), current_time( 'timestamp' ) ) . ' ago';
?>

tahirtaous

// This code will show message only on mobile devices
// only mobile users will see this message
// Source: https://www.cms2cms.com/blog/6-useful-yet-relatively-unknown-wordpress-functions/
// Tested: WordPress 4.1 Jan 25 2015
<?php if( wp_is_mobile() ) : ?>
Visit our website on your desktop for a richer user experience
<?php endif ?>