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update_attributes and associations - customizing rails magic

For sources in Rriki the user types in a list of authors for that publication and RRiki takes care of looking up the database of known authors, creating new entries if need be and then linking the relevant authors to the publication. This is all good and dandy for the user, but editing poses a problem: update_attributes takes its information from the form, which does not have the association information.

From api.rubyonrails.org we have :

def update_attributes(attributes)
self.attributes = attributes
save
end

All that was needed was to not use the bundled update_attributes and instead manually do

@source.attributes = params[:source]
@source.attach_authors_to_this_source
@source.save

Another instance where it is necessary to break into the comfy 'it just works' world of rails and customize some of the magic.
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Comments

  1. TarunJanuary 29, 2009 at 11:11 AM

    I happen to face a similar problem, but I use auto complete fields on the forms and then link them in the update method.

    ReplyDelete
  2. Ruby on Rails CompanyJune 8, 2012 at 7:43 AM

    @ Tarun: i have tried the similar approach what you have taken but in my case its not working ???

    ReplyDelete

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