Customize and Remove WordPress Admin Panel Items/Widgets

<?php
/*****************************************
 * WordPress Admin Customization Snippets
 *
 * These are several snippets that can be used to customise your WordPress Admin Dashboard
 * by removing specific elements/items from it and even adding custom ones.
 *
 * These can be added to a plugin or theme's functions.php file and customised as needed.
 * I HIGHLY recommend renaming the functions with more unique names to lessen the potential
 * for name collisions with other plugins/themes.
 */

/**
 * Remove WP Admin Menu Panels
 *
 * This hides complete groups from the admin menu, such as 'Links', 'Media', 'Pages', etc.
 * The sections are still accessible by typing in the direct URL, but they are removed
 * from the menu itself.
 *
 * @link    http://sixrevisions.com/wordpress/how-to-customize-the-wordpress-admin-area/
 * @param   void
 * @return  void
 */
function remove_menu_items()
{
    global $menu;
    // The menu items to hide
    $restricted = array( __('Links'),    __('Comments'),    __('Media'),
                         __('Plugins'),  __('Tools'),       __('Users'),
                         __('Settings'), __('Appearance'),  __('Pages'), __('Posts')
    );
    // Move array pointer to the end of the array and loop backwards
    end($menu);
    while( prev($menu) )
    {
        $value = explode(' ',$menu[key($menu)][0]);
        if( in_array($value[0] != NULL?$value[0]:"" , $restricted) )
            unset( $menu[key($menu)] );
    }
}
add_action('admin_menu', 'remove_menu_items');

/**
 * Remove WP Admin Dashboard Widgets
 *
 * This removes the various widgets from the admin dashboard so un-needed dashboard items
 * can be hidden to decrease clutter.
 *
 * @link    http://sixrevisions.com/wordpress/how-to-customize-the-wordpress-admin-area/
 * @param   void
 * @return  void
 */
function remove_dashboard_widgets()
{
    global$wp_meta_boxes;
    // All of these will strip most dashboards of ALL widgets.  Comment out the ones needed...
    unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_plugins']);
    unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_recent_comments']);
    unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_primary']);
    unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_incoming_links']);
    unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_right_now']);
    unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_quick_press']);
    unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_recent_drafts']);
    unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_secondary']);
}
add_action('wp_dashboard_setup', 'remove_dashboard_widgets');

/**
 * Custom WP Dashboard Widget Contents
 *
 * This adds the contents for a custom dashboard widget and called by
 * add_your_dashboard_widget().
 *
 * @link    http://wp-snippets.com/82/add-a-dashboard-widget/
 * @param   void
 * @return  void
 */
function your_dashboard_widget() { ?>
    <h3>Hello WordPress user!</h3>
    <p>Fill this with HTML or PHP.<br>
    Just imagine all the stuff you can put here!</p>
    <p>The possibilities are endless and that's no joke!</p>
<?php
}

/**
 * Add Custom WP Dashboard Widget
 *
 * This will add a custom dashboard widget to WordPress, allowing for customized dashboard
 * contents.
 *
 * @uses    your_dashboard_widget() Calls function to add contents for custom widget.
 * @link    http://wp-snippets.com/82/add-a-dashboard-widget/
 * @param   void
 * @return  void
 */
function add_your_dashboard_widget() {
    wp_add_dashboard_widget( 'your_dashboard_widget', __( 'Widget Title!' ), 'your_dashboard_widget' );
}
add_action('wp_dashboard_setup', 'add_your_dashboard_widget' );

/**
 * Add Custom Help Page
 *
 * Adds custom help contents to the 'Help' tab in WordPress's admin area.
 * This will be added to whichever pages it is hooked to.
 *
 * By using this function to hook the contextual_help hook, we limit the custom
 * help contents from being added to EVERY page.
 * If you want it to show on every page's help dropdown, just add the filter hook in
 * this function directly below the custom_page_help() function.
 *
 * @link    http://wp-snippets.com/98/edit-the-help-dropdown/
 * @uses    custom_page_help() Calls function to render the custom help contents.
 * @param   void
 * @return  void
 */
function add_custom_help_page() {
   //the contextual help filter
   add_filter('contextual_help','custom_page_help');
}

/**
 * Custom Help Page Contents
 *
 * This renders the custom help contents.  If the parameter $help is not echoed,
 * then the existing help contents will be excluded in the help dropdown.
 *
 * @link    http://wp-snippets.com/98/edit-the-help-dropdown/
 * @param   string  $help   The existing help contents
 * @return  void
 */
function custom_page_help($help) {
   // Keep the existing help copy - comment the following line to exclude existing help contents.
   echo $help;

   // Add the new help contents
   echo "<h5>Custom Features</h5>";
   echo "<p>Content placed above the more divider will appear in column 1. Content placed ".
        "below the divider will appear in column 2.</p>";
}
// Specify a specific page to hook to like so: 'load-<specific page>.php'
add_action('load-my-sites.php','add_custom_help_page');
add_action('load-index.php','add_custom_help_page');

/**
 * Replace the Admin Footer Text
 *
 * Overrides the admin footer text with your own custom text.
 *
 * @link    http://wp-snippets.com/59/change-footer-text-in-wp-admin/
 * @param   void
 * @return  void
 */
function remove_footer_admin () {
  echo 'My footer text. Thank you <a href="http://wordpress.org">WordPress</a> for giving me this filter.';
}
add_filter('admin_footer_text', 'remove_footer_admin');

/**
 * Hide Update Notifications in WordPress
 *
 * @link    http://wp-snippets.com/79/disable-wordpress-update/
 */
add_filter( 'pre_site_transient_update_core', create_function( '$a', "return null;" ) );

/**
 * Change the WP Version in Footer
 *
 * You can hide the version all together, replace it with something else, or spoof the
 * version to show as something else.
 *
 * @link    http://wp-snippets.com/701/change-version-in-wp-admin-footer/
 * @param   void
 * @return  void
 */
function change_footer_version() {
    return 'Version 120.0.0';
}
add_filter( 'update_footer', 'change_footer_version', 9999 );

/**
 * Hide WP Admin Screen Options tab
 *
 * This will hide the 'Screen Options' tab at the top-right in the WordPress admin area.
 *
 * @param   void
 * @return  bool    false   Keeps WordPress from rendering the Screen Options tab
 */
function hide_screen_options() {
    return false;
}
add_filter('screen_options_show_screen', 'hide_screen_options');