I think I have found out why this isn't working.
Its the Get function, this part isnt right: ArticlePageID = $this->ID. When I just have ArticlePageID, all of the ArticleBilde are showing in a list. SS doesn't know what do get and doesn't output anything..
I'm not that good at programming this kind of things, so how should I do this when I have an articleholder with serveral ArticlePages with images added to them, something like this:
Articleholder -> ArticlePage1 -> ArticleBilde1,ArticleBilde2,ArticleBilde2,
-> ArticlePage2 -> ArticleBilde1,ArticleBilde2,
-> ArticlePage3 -> ArticleBilde1,ArticleBilde2,
Heres the function:
$manager = DataObject::get_one("ArticlePage");
return ($manager) ? DataObject::get("ArticleBilde", "ArticlePageID = $this->ID", "SortOrder") : false;