I want to include a piece of custom javascript....But

I only want this to happen if BannerPage has items in the DataObject Banner.

$this->ShowBanner can successfully check on a field within BannerPage.

But i want to check if this BannerPage actually has images in the Dataobject called Banner

---banner.php dataobject --that holds field bannerimage
class Banner extends DataObject {

}

-- BannerPage --
class BannerPage extends Page {

public static $db = array(

'ShowBanner' => 'Boolean'
);

}

class BannerPage_Controller extends Page_Controller {

public function init() {
parent::init();

if($this->ShowBanner){
Requirements::customScript("

myjscode",bannerjs');

}else {

}

}//init

}//controller

I previously did <% if Banners %> in template but i want to now add js via the Controller instead

Maybe i need to add a function ??

public function CheckBanners() {
return DataObject::get("Banner", "PageID = {$this->ID}");
}

I don't see any relationship between your BannerPage and the Banner object, such as has_one or has_many. But once you add a relationship, you can check for the existence of banners by doing this:

if($this->Banners()) {
//do something here
}