"Blog", ); public function getCMSFields() { $this->beforeUpdateCMSFields(function($fields) { $fields->push( DropdownField::create("BlogID", _t("BlogCategoriesWidget.Blog", "Blog"), Blog::get()->map()) ); }); return parent::getCMSFields(); } public function getCategories() { $blog = $this->Blog(); if($blog) { return $blog->Categories(); } return array(); } } class BlogCategoriesWidget_Controller extends Widget_Controller { } }