Ruby on Rails 4 - simple_form multiple select input

Question

I have a simple_form input field that looks like this:

<%= f.input :particular_users, collection: @all_users, input_html: { class: 'multiselectuser', multiple: true} %>

When I leave multiple: true off, the form submits the chosen value for the parameter :particular_users and I can see the value when debugging using "raise params.inspect". However when I leave the multiple: true option there, no vales get passed for the parameter :particular_users.

What am I doing wrong?

EDIT: I can not use the association input because :particular_users is a virtual attribute and has no relationship. I want the multiple select box to pass whatever values that are in there, even if they are arbitrary.

Chartist

Answer 1

It actually does work the way I wanted it to. The trick is to tell the strong parameters to allow a hash. It doesn't throw a strong parameters error, the param just gets thrown out and doesn't come through. So I set it to for example: params.require(:survey).permit(:particular_users => []).

Chartist

Did you figure this out? I have an array whitelisted in my strong params but cannot figure this out. #41628457 – Wellborn

Answer 2

f.input :days, collection: @your_collection, input_html: { multiple: true }

Farci

can you explain what you are doing here. that would help out a lot – Hustle

if you use simple_form gem and want multiple select just add this attribute to input_html – Farci

For some reason, it is not allowing to unselect. – Tawnytawnya

Answer 3

To create multiple select tags with simple_form, use:

<%= f.association :particular_users, collection: @all_users, input_html: { class: 'multiselectuser'} %>

see part Associations in the gem description.

But as you don't want to use an ActiveRecord associaion, use select_tag:

<%= select_tag 'particular_users', 
       options_from_collection_for_select(@all_users, :id, :name), 
       multiple: true, class: 'multiselectuser' %>

Embrace

I receive the error: Association :particular_users not found because :particular_users is a virtual attribute and not an association. I don't want to select an association, I just want the params to pass what is in the multiple select box even if they are arbitrary values. – Chartist

then simple_form is not the right tool for you. Use select_tag to build your custom select. – Embrace

It is actually what I want. I posted the correct answer. – Chartist