Hide page in the admin per user per page/branch

HiddenAdminPages.module

<?php

/**
 * UserWorkspaces
 *
 * Example module to hide page in the admin per user per page.
 *
 * ProcessWire 2.x
 * Copyright (C) 2010 by Ryan Cramer
 * Licensed under GNU/GPL v2, see LICENSE.TXT
 *
 * http://www.processwire.com
 * http://www.ryancramer.com
 *
 */

class HiddenAdminPages extends WireData implements Module {

    public static function getModuleInfo() {

        return array(
            'title' => 'HiddenAdminPages',
            'version' => 100,
            'summary' => 'Example module to hide page in the admin per user per page.
                          Add a page field "pagelist_hidden" with a PageListSelectMultiple input type
                          to the user template. Select or add pages you want to hide in the admin.',
            'href' => '',
            'singular' => true,
            'autoload' => true
            );
    }


    public function init() {
        // only add hook only if the render parameter is set
        // (as used by ProcessPageList)
        if(!isset($_GET['render'])) return;

        if(!$this->templates->get("user")->hasField('pagelist_hidden')) return;
        if(!count($this->user->pagelist_hidden)) return;

        $this->addHookAfter('ProcessPageList::execute', $this, 'pageListHiddenPages');
    }


    public function pageListHiddenPages(HookEvent $event){

        // create an array with all id's of the page to exclude
        $hidden = explode('|',$this->user->pagelist_hidden);

        // make sure it's an ajax request
        if($this->config->ajax){
            // manipulate the json returned and remove any pages found from array
            $json = json_decode($event->return, true);
            foreach($json['children'] as $key => $child){
                if(in_array($child['id'],$hidden)) unset($json['children'][$key]);
            }
            $json['children'] = array_values($json['children']);
            $event->return = json_encode($json);
        }

    }

}