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DataObjectManager Module /

Discuss the DataObjectManager module, and the related ImageGallery module.

Moderators: martimiz, UncleCheese, Sean, Ed, biapar, Willr, Ingo, swaiba

Extending more than one "level"?

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4 Posts   1145 Views


Community Member, 66 Posts

29 August 2009 at 8:42am


I am having problems getting the DataObjectManager to properly associate items when it is being used in more than one level of class inheritance. (sorry if I am using the wrong language to describe this!)

Here is what I have now:

In the "Page" class itself I am adding a "has_many" relationship to "BannerImages"

"ArticlePage" extends "Page" and has two additional "has_many" relationships, one to "ArticleImages" and another to "ArticleFiles"

ArticleImages and ArticleFiles work beautifully.

But BannerImages keeps getting associated with seemingly all, or random, Pages and ArticlePages! What gives?

I took a peak at the database table BannerImage and see that the PageID is the foreign key. Do my ArticlePages use a PageID, too, or does ArticlePageID override that?

Thanks for any insight!



Forum Moderator, 4102 Posts

29 August 2009 at 9:29am

Hi, Jeremy,

Make sure you have your model set up as follows:

Page -> has_many "BannerImages"
BannerImage -> has_one "Page"

ArticlePage -> has_many "ArticleImages"
ArticlePage -> has_many "ArticleFiles"

ArticleFile -> has_one "ArticlePage"
ArticleImage -> has_one "ArticlePage"

If you're using a DOM on Page class, you need to be sure to use setParentClass("Page") because you're passing $this as the controller and if $this is an ArticlePage, it will try to set ArticlePageID on your BannerImage, which of course is a non-existent field.


Community Member, 66 Posts

29 August 2009 at 11:45am

Thanks UncleCheese...

I did triple-check the model has_many and has_one, and I know that is working.

Does the "setParentClass" go in the getCmsFields of ArticlePage then?

I am familiar with DOM for HTML and JavaScript, but not with PHP.

Thanks again!


Community Member, 66 Posts

29 August 2009 at 11:45am

D'oh, I just realized DOM is short for DataObjectManager... sorry! I will try your suggestion.