silverstripe-subsites/code/forms/SubsitesTreeDropdownField.php

<?php
/**
 * Wraps around a TreedropdownField to add ability for temporary
 * switching of subsite sessions.
 * 
 * @package subsites
 */
class SubsitesTreeDropdownField extends TreeDropdownField
{
    private static $allowed_actions = array(
        'tree'
    );
    
    protected $subsiteID = 0;
    
    protected $extraClasses = array('SubsitesTreeDropdownField');
    
    public function Field($properties = array())
    {
        $html = parent::Field($properties);
        
        Requirements::javascript('subsites/javascript/SubsitesTreeDropdownField.js');
        
        return $html;
    }
    
    public function setSubsiteID($id)
    {
        $this->subsiteID = $id;
    }
    
    public function getSubsiteID()
    {
        return $this->subsiteID;
    }
    
    public function tree(SS_HTTPRequest $request)
    {
        $oldSubsiteID = Session::get('SubsiteID');
        Session::set('SubsiteID', $this->subsiteID);
        
        $results = parent::tree($request);
        
        Session::set('SubsiteID', $oldSubsiteID);
        
        return $results;
    }
}