What I have now gives me a dropdown menu where I can only select one:
<%= form_for(@submission) do |f| %>
<%= f.collection_select :id, Submission::SUB_ID, :to_s, :to_s %>
<% end %>
where SUB_ID=[1,2,3] in model Submission
I want to implement a checkbox instead of a dropdown menu so that I can select multiple SUB_ID (i.e. 1&2 or 1&3 or 2&3 or 1&2&3). I tried to use this but it does not work:
<%= f.check_box :id, Submission::SUB_ID, :to_s, :to_s %>
Any idea?
Try this:
# view
<%= form_for(@submission) do |f| %>
<%= Submission::SUB_ID.each do |sub_id| %>
<%= f.checkbox 'ids[]', value: sub_id, checked: @submission.id == sub_id %>
<%= sub_id %>
<% end %>
<% end %>
# controller
params[:submission][:ids].each do |checked_sub_id|
# do your logic here
end
you have to iterate over SUB_ID somehow like this...
<% Submission::SUB_ID.each do |ssid| %>
<%= f.check_box "ids[]", value: ssid %>
<% end %>
or you can use formtastic gem. it has :as=>:check_boxes input fields http://www.ruby-doc.org/gems/docs/n/nuatt-formtastic-0.2.3/Formtastic/Inputs/CheckBoxesInput.html
The core answer is you need to loop over each item in Submission::SUB_ID and make a checkbox for each id. Depending on how your models are set up and what you want to do - you may need to be much more involved in the form building. I hesitate to provide specific examples without know more about how you want the data to come back to the controller
<%= form_for(@submission) do |f| %>
<% Submission::SUB_ID.each do sub_id %>
<%= f.check_box_tag 'submission_ids[]', sub_id %>
<% end %>
<% end %>
Note that that will not default anything to checked and it does not come back as part of the submission parameters.
Usually when I have a similar situation I'm using nested forms to add or remove objects.
If you're using Rails 4, there is a new helper, collection_check_boxes, which helps streamline the building of your check boxes.
<%= f.collection_check_boxes :submission_ids, Submission::SUB_ID, :to_s, :to_s %>
Documentation:
If you look at the documentation in the second link, you'll also find how to use the optional block syntax to customise the HTML structure for each check box.
