simple_form: Check boxes and hidden input problem

Hi guys!

I am using simple_form 2.0.2 with rails 3.2.3. I have a simple model called Movie with a serialized field ‘resolutions’:

class Movie < ActiveRecord::Base
  serialize :resolutions, Array
end

The simple_form looks like this:

<%= simple_form_for @movie do |f| %>
  <%= f.input :resolutions, :collection => ["SD", "ED", "HD"], :as => :check_boxes %>
<% end %>

The problem is, that simple_form adds the following input tag (with no value) after the 3 input tags for the collection:

<input name="movie[resolution][]" type="hidden" value>

When the form gets submitted with only the “SD” checkbox selected, the params looks like this:

"resolutions"=>["SD", ""]

and the Movie instance gets updated accordingly:

irb(main):022:0> m.resolutions
=> ["SD", ""]

The problem is that, I don’t want the empty string present in the resolutions field. And in case all checkboxes are uncheck, the params contains “resolutions”=>[“”] instead of “resolutions”=>[]. Any suggestions?

About this issue

Original URL
State: closed
Created 12 years ago
Reactions: 5
Comments: 21

Most upvoted comments

I believe this issue persists with rails 5.0.0.1. I am adding include_hidden: false but i still get empty values

= f.association :answers, label: false,
  collection: @poll.questions[f.options[:child_index].to_i].answers,
  as: :check_boxes, include_hidden: false

+12

adavia on Nov 28, 2016

Still have the same issue with a select. include_hidden: false has no effect.

ncri on May 3, 2018

It’s not a SimpleForm’s thing but Rails’s. You can read a bit about this here https://github.com/rails/rails/issues/5402 Note, :include_hidden option will be added in Rails 4

nashby on Jun 27, 2012

@leoniddinershtein sorry, looks like I forgot to add this option to collection_check_boxes helper in Rails (or it didn’t exist at that time). Anyway, I made a PR to Rails https://github.com/rails/rails/pull/12662. So after it releases you’ll be able to use it like this:

f.input :resolutions, :collection => ["SD", "ED", "HD"], :as => :check_boxes, :include_hidden => false

but right now it works only with Rails’s select helper I guess…

nashby on Oct 27, 2013

Using latest version of rails this worked it for me ( using simple_form ) as it removed the leading “” in the hash.

<%= f.collection_check_boxes :tags, Tag.all, :tag, :tag, as: :boolean, include_hidden: false %>

scoobyclub on May 28, 2019

@eikes Thank your suggestion, for your code snippet, need to change reject method to reject!. Otherwise it won’t save it to db.

class Movie < ActiveRecord::Base
  serialize :resolutions, Array

  before_save :clean_resolutions

  def clean_resolutions
    resolutions.reject! { |r| r.blank? }
  end
end

thattimc on Mar 9, 2015