Pass values from select_tag in params

Question

I created a "select_tag" field and I need it when the user clicks save all the values of this field to be passed by params to the controller. The problem is that when I click save, only the first value entered in this field is passed to the controller.

To better understand, the "select_tag" field is populated through another field, the "f.text_field :members" field. When I click on an "add" button the value of the "f.text_field :members" field is passed to the "select_tag" field and so I want to be able to check all these values from the "select_tag" field to validate and save, how do I do that? As I already said, only the first value entered is passed.

Looking at the params now, I realized that the value that returns as "params" is just the value that is selected in the dropdown, the other values are not considered. How do I pass all values in the dropdown?

Code:

<%= form_for(@focus_group) do |f| %>
  <% if @focus_group.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@focus_group.errors.count, "error") %> prohibited this focus_group from being saved:</h2>

      <ul>
      <% @focus_group.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
  <script type="text/javascript">
  $(function() {
    $('#focus_group_moderator, #focus_group_members').autocomplete({
      source: '/focus_groups/autocomplete.json'
    });
  });
  function add(){
    var value = $('#focus_group_members').val();
    var select = document.getElementById("membersAdded");
    var option = document.createElement("option");
    option.text = value;
    option.value = value;
    select.add(option);

    $('#focus_group_members').val("");
  }

  function removeFromSelect(){
    var select = document.getElementById("membersAdded");
    select.remove(select.selectedIndex);
  }
  </script>
  <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
  </div>
  <div class="field">
    <%= f.label :topic %><br>
    <%= f.text_field :topic %>
  </div>
  <div class="field">
    <%= f.label :moderator %><br>
    <%= f.text_field :moderator %>
  </div>
  <div class="field">
    <%= f.label :description %><br>
    <%= f.text_area :description %>
  </div>
  <div class="field">
    <%= f.label :members %><br>
    <%= f.text_field :members %>
    <input onclick="add()" type="button" value="Add" /><br>
    <%= select_tag(:membersAdded, options_for_select([])) %>
    <input onclick="removeFromSelect()" type="button" value="Remove" /><br>
    <br>
  </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

CONTROLLER

class FocusGroupsController < ApplicationController
  before_action :set_focus_group, only: [:show, :edit, :update, :destroy]
  include FocusGroupsHelper

  def index
    if(params[:term])
      @profile = Profile.all.select("name", "id")

      @lista = Array.new

      @profile.each do |x|
        @lista.push(x.name)
      end

      respond_to do |format|
        format.html
        format.json { render json: @lista.to_json}
      end
    else
      @focus_groups = FocusGroup.all
    end
  end

  def show
  end

  def new
    @focus_group = FocusGroup.new
    @membersAdded

    respond_to do |format|
      format.html
      format.json { render json: Profile.all.to_json}
    end
  end

  def edit
  end

  def create
    @moderator= find_profiles_id(focus_group_params[:moderator])
    @moderator.each do |f|
      @moderator_id = f.id
    end

    @params = focus_group_params
    @params[:moderator] = @moderator_id

    @focus_group = FocusGroup.new(@params)

    if @focus_group.save
      redirect_to @focus_group, notice: 'Focus group was successfully created.'
    else
      render :new
    end
  end

  def update
    if @focus_group.update(focus_group_params)
      redirect_to @focus_group, notice: 'Focus group was successfully updated.'
    else
      render :edit
    end
  end

  def destroy
    @focus_group.destroy
    redirect_to focus_groups_url, notice: 'Focus group was successfully destroyed.'
  end

  def autocomplete
    if(params[:term])
      @profile = Profile.all.where("user_id <> 0 and is_template = 'f' and name LIKE ?", "#{params[:term]}%").select("name", "id")

      @lista = Array.new

      @profile.each do |x|
        @lista.push(x.name)
      end

      respond_to do |format|
        format.html
        format.json { render json: @lista.to_json}
      end
    end
  end

  def find_profiles_id(name)
    return Profile.all.where("name LIKE ?", "#{name}%").select("id")
  end

  def find_profiles_name(id)
    @profile = Profile.all.where("id = ?", "#{id}").select("name")

    @profile.each do |e|
      @name = e.name
    end
    return @name
  end

  private

    def set_focus_group
      @focus_group = FocusGroup.find(params[:id])
    end

    def focus_group_params
      params.require(:focus_group).permit(:name, :topic, :moderator, :description, :members, :membersAdded)
    end
end

Answer 1

Several ways to approach this -- but the select box itself doesn't make any sense to use in this situation. Provides no utility. Here's one way. Do you have a separate members model? It seems like you're essentially trying to do a nested form. If you don't have a members model, create one. Create a focus group separately and put the form for members on the FocusGroup's show page. A focus group has many members and member belongs to a focus group (has a focus group id). This will allow you to say @focus_group.members and get all the members back.

If you must add them on the same form for some reason (I don't think this is optimal), you'll want to do so via a nested form with a form builder that allows you to add many at once. You could also make a service object but that is more complicated.

Another option, which I like less, would be to push all of the members to an array and then pass it as a param on submit. Instead of adding the members to the select box you'd just push them to an array. Then you would set the final array value to members_added (or whatever you name the parameter). You'll need to unpack that array in the controller to create each member. I like this much less. The first option is the cleanest. I think this is the third best approach of the three.