Rails Cascading Drop Down List: Change Drop down menu into Text Field based on Previous Drop Down Option Selected

Question

In my Rails Application I have a Country Select Option Drop down list using the country_select gem,and next to the country select drop down there is another dropdown to display the states in "US" like the code bellow:

CODE OF COUNTRY SELECT DROP DOWN

<div class="row">
    <div class="form-group">
      <%= f.label :country,'Country', class:"control-label"%>
      <%= f.country_select(:country ,  {priority_countries: [ "US"]} ,{class: "form-control"}) %>
    </div>
</div>

CODE OF STATE SELECT DROP DOWN

      <%= f.label :state,'State', class:"control-label" , style: "color: black;"%>
      <%= f.select( :state, options_for_select(us_states), {}, {class: "form-control"}) %>

Here us_states method is defined in application_helper.rb file like bellow:

def us_states
    [
        ['Alabama', 'AL'],
        ['Alaska', 'AK'],
        ['Arizona', 'AZ'],
     ...............etc
    ]

  end

Here the default selected country is "US", but if the user select any other country from the country select drop down then I want make the state select drop down into a normal text field not a drop down list . How can I make the state select drop down into a text field if the user select a country other than US ? And if the selected country is US the state section must stay as a drop down ?

Answer 1

I would recommend to add both Text Field and State dropdown initially and toggle them depending on Country value.

<%= f.label :state,'State', class:"control-label" , style: "color: black;"%>
<%= f.select( :state, options_for_select(us_states), {}, {class: "form-control"}) %>
<%= f.text_field :state,'', class: "form-control",:style=>"display:none"%>

Now add toggle logic in jquery

<script type='text/javascript'>
    $("#country_drop_down_id").change(function(){
    if($(this).val()=='US'){
       $('#state_drop_down_id').show();
       $('#state_text_field_id').hide();
    }else{
       $('#state_drop_down_id').hide();
       $('#state_text_field_id').show();
    }
    });
 </script>

Replace country_drop_down_id , state_drop_down_id , state_text_field_id with corresponding ID selector.