Hide certain widgets from specific user roles in admin

Question

I'm looking for a way to hide certain widgets from specific user types in the admin, Appearance > Widgets page?

For instance, admins can see all widgets, but authors can only see a select few?

I noticed there was a Code Canyon plugin, but it requires a framework with it also which I am not using.

Answer 1

You have to check for Roles and Capabilities in the action hook widgets_init and proceed accordingly.

add_action( 'widgets_init',  'remove_widgets_wpse_89138' , 15 );

function remove_widgets_wpse_89138()
{
    // http://codex.wordpress.org/Function_Reference/is_admin
    if( !is_admin() )
        return;

    // Grab current user info
    global $current_user;

    // Check for specific user
    /*
    $username = $current_user->user_login;
    if( 'the_user_login' != $username)
        return;
    */

    // Check for capability
    if( current_user_can( 'add_users' ) )
        return;

    unregister_widget( 'WP_Widget_Pages' );
}

Q&A's of interest:

• Prevent widgets removal

• Limit number of Widgets in Sidebars

Answer 2

I actually have a class which i use just for that:

/**
* Hide_widgets_role_based
* @author Ohad Raz <[email protected]>
*/
class Hide_widgets_role_based{
    $has_selector = false;
    $js_selector = '';
    $roles_hide =array();
    /**
     * class constructor
     * @author Ohad Raz <[email protected]>
     * @param array $args [description]
     */
    function __construct($args = array()){
        if (is_admin())
            add_action('widgets_init', array($this,'hide', 999));
    }

    /**
     * the money function that hides the widgets on the admin side when the user has a specific role
     * @return void
     */
    public function hide(){
        global $pagenow;
        if ($pagenow == 'widgets.php'){
            global $current_user;
            get_currentuserinfo();
            $sperator = "";
            foreach ($this->roles_hide as $role => $widgets) {
                if ($this->has_role($role)){
                    foreach ((array)$widgets as $w_id) {
                        unregister_widget( $w_id );
                    }
                }
            }
        }
    }


    /**
     * add a widget to hide per role
     * @param string $role   role name
     * @param string $widget widget id
     */
    public function addHide($role,$widget){
        if (is_array($widget)){
            $tmp = isset($roles_hide[$role])? $roles_hide[$role]: array();
            $roles_hide[$role] = array_merge($tmp, (array)$widget);
        }else{
            $roles_hide[$role][] = $widget;
        }
    }

    /**
     * has_role check if a user has a role
     * @param  int  $user_id user id
     * @return boolean          
     */
    public function has_role($user_id = null){
        if ( is_numeric( $user_id ) )
            $user = get_userdata( $user_id );
        else
            $user = wp_get_current_user();

        if ( empty( $user ) )
        return false;

        return in_array( $role, (array) $user->roles );
    }
}

Usage:

$widgets_hide = new Hide_widgets_role_based();
$widgets_hide->addHide('contributor',array('WP_Widget_Pages','WP_Widget_Calendar','WP_Widget_Links'));
$widgets_hide->addHide('editor','WP_Widget_Links');