Comments on: Multiselect control in Rails with a Many to Many relationship

By: Family Sociology

Family Sociology — Tue, 23 Mar 2010 12:31:32 +0000

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By: Dmitry Polushkin

Dmitry Polushkin — Sun, 15 Nov 2009 09:48:22 +0000

Hi, you can change @restaurant.categories.collect { |cat| cat.id}) into @restaurant.category_ids. Also, I think it’s better to assign this values to variables in controller. :)

Anyway thanks for this post.

By: Anonymous

Anonymous — Wed, 22 Apr 2009 03:13:00 +0000

I know, it’s a 1y old post. Anyway i’m sure a lot of visitors drop in this article so…

@animeword
In your create and update method change “@params” in “params” (no @ is needed)

By: Thomas Rekittke

Thomas Rekittke — Sat, 04 Apr 2009 12:21:00 +0000

Nice article. There is another way for multiselect (for has_many and habtm relationships) though – showing two select boxes, one for all available options and one for the selected options, and the opportunity to move options from one select box to the other. I call this SwapSelect and is described (incl. download) here: http://trendwork.kmf.de/175

By: animeworld

animeworld — Sat, 08 Nov 2008 09:35:00 +0000

Hi folks!
I got the following error:

You have a nil object when you didn't expect it!
You might have expected an instance of ActiveRecord::Base.
The error occurred while evaluating nil.[]
app/controllers/restaurants_controller.rb:44:in `create'

Parameters:

{"restaurant"=>{"name"=>"Restaurant do Leandro"},
"commit"=>"Create",
"authenticity_token"=>"bdad0a7ac7b929c1200fc2e48f997f5e86eb87a1",
"category_ids"=>["1"]}

someone could help me?

By: Eric

Eric — Mon, 24 Mar 2008 09:56:00 +0000

Great little article! Helped me out, thanks!

By: Cory Foy

Cory Foy — Fri, 15 Feb 2008 08:53:00 +0000

Thanks Scott. The way to get around that would simply be to populate an @categories variable and an @selected_categories variable in the control that the view would use.

Thanks for the reminder!

By: Scott Bellware

Scott Bellware — Fri, 15 Feb 2008 01:08:00 +0000

Cory,

It’s usually considered bad practice to data access calls from the view. It’s much, much harder to document the data access through TDD specifications since some of the data access is in the view, and testing views requires a different kind of testing.