Adjusting the WordPress top admin toolbar

add-link-top-admin-menu.php

//
// Example 1. Adding a node (sub menu link) to the site name menu.
//
// The following code adds a media library link to the site name drop down menu.
add_action( 'admin_bar_menu', 'add_link_to_admin_bar',999 );

 function add_link_to_admin_bar($wp_admin_bar) {         
          // adds a child node to site name parent node
          $wp_admin_bar->add_node( array(
                'parent' => 'site-name',
                'id'     => 'media-libray',
                'title'  => 'Media Library',
                'href'   => esc_url( admin_url( 'upload.php' ) ),
                'meta'   => false
       		));
 }    

add-links.php

//
// Example 2. Adding two nodes (sub menu links) to the site name menu.
//
// If your using the code in the beginning of your functions.php file then include the <?php before the below code. 
// The following code adds a media library and a plugins link to the site name drop down menu.
add_action( 'admin_bar_menu', 'add_links_to_admin_bar',999 );

function add_link_to_admin_bar($wp_admin_bar) {         
          // adds the child node media library to site name parent node
          $wp_admin_bar->add_node( array(
                'parent' => 'site-name',
                'id'     => 'media-libray',
                'title'  => 'Media Library',
                'href'   => esc_url( admin_url( 'upload.php' ) ),
                'meta'   => false
       		));
       		
       	// adds the child node plugins to site name parent node
          $wp_admin_bar->add_node( array(
                'parent' => 'site-name',
                'id'     => 'plugins',
                'title'  => 'Plugins',
                'href'   => esc_url( admin_url( 'upload.php' ) ),
                'meta'   => false
       		));
 }

add-nodes-to-admin-bar.php

//
// Example 3. Adding a top level node I named Custom Made having it link to an external web site. 
// Adding two nodes (sub menu links) Media Library and Plugins to the Custom Made menu.
//
// The following code adds a top level link and media library and plugins submenu links to the Custom Made drop down.
add_action( 'admin_bar_menu', 'add_nodes_to_admin_bar',999 );

 function add_nodes_to_admin_bar($wp_admin_bar) {
         // adds a top level parent node I called Custom Made 
        $wp_admin_bar->add_node( array(
         		'id'    => 'custom',
         		'title' => 'Custom Made',
         		'href'   =>  'http://easywebdesigntutorials.com/', // Top level link Custom Made links to an external web site.
         ));
         
         // adds the child node Media Library to Custom Made 	
         $wp_admin_bar->add_node( array(
         		'parent' => 'custom',
         		'id'     => 'media-libray', // If you reuse media library in two locations then the id name of the second link needs to be different.
         		'title'  => 'Media Library',
         		'href'   => esc_url( admin_url( 'upload.php' ) ),
         		'meta'   => false		
         ));
         	
         // adds the child node Plugins to Custom Made	
         $wp_admin_bar->add_node( array(
         		'parent' => 'custom',
         		'id'     => 'plugins',
         		'title'  => 'Plugins',
         		'href'   => esc_url( admin_url( 'plugins.php' ) ),
         		'meta'   => false		
         	));   
 } 

my-custom-menu.php

//
// Example 4. Removing all customizer links. 
// Adding multiple nodes (sub menu links) Media Library, Plugins, Themes, All Pages, All Posts to the site name menu.
//
// Here is a top admin sub menu that I made to be included inside the site name menu.
add_action( 'admin_bar_menu', 'remove_customize',999 );
 function remove_customize ($wp_admin_bar) {
 	 // Removes all customizer links from the admin menu bar. 
   // Any of the top admin bar links can be removed in this way.
 		    $wp_admin_bar->remove_node( 'customize' );  
 		    $wp_admin_bar->remove_node( 'customize-background' );   
 	    	$wp_admin_bar->remove_node( 'customize-header' ); 
 	    	$wp_admin_bar->remove_node( 'customize-themes' );   
 	    	$wp_admin_bar->remove_node( 'customize-widgets' );       	    	  
 }

add_action( 'admin_bar_menu', 'add_nodes_to_admin_bar',999 );
 function add_nodes_to_admin_bar($wp_admin_bar) {    
         // Adds the child node Media Library to the site name parent node (submenu)
          $wp_admin_bar->add_node( array(
          		'parent' => 'site-name',
          		'id'     => 'media-libray', // NB! The id name can only be used once.
          		'title'  => 'Media Library',
          		'href'   => esc_url( admin_url( 'upload.php' ) ),
          		'meta'   => false		
          ));	   	
         	
         // Adds Plugins.
         $wp_admin_bar->add_node( array(
         		'parent' => 'site-name',
         		'id'     => 'plugins', 
         		'title'  => 'Plugins',
         		'href'   => esc_url( admin_url( 'plugins.php' ) ),
         		'meta'   => false		
         	));	  
         	
         // Adds Themes.
         $wp_admin_bar->add_node( array(
         		'parent' => 'site-name',
         		'id'     => 'themes', 
         		'title'  => 'Themes',
         		'href'   => esc_url( admin_url( 'themes.php' ) ),
         		'meta'   => false		
         	));	    
         	
         // Adds All Pages.
         $wp_admin_bar->add_node( array(
         		'parent' => 'site-name',
         		'id'     => 'all-pages', 
         		'title'  => 'All Pages',
         		'href'   => esc_url( admin_url( 'edit.php?post_type=page' ) ),
         		'meta'   => false		
         	));	 
         	
         // Adds All Posts.
         $wp_admin_bar->add_node( array(
         		'parent' => 'site-name',
         		'id'     => 'all-posts', 
         		'title'  => 'All Posts',
         		'href'   => esc_url( admin_url( 'edit.php' ) ),
         		'meta'   => false		
         	));	  				 		  	                	         	         	 	         		 
 } 

remove-admin-toolbar.php

// Example 5. Remove the admin toolbar.
//
// The following code removes the admin toolbar.
add_filter('show_admin_bar', '__return_false');