Question

I have in my rails form the following code:

<label>Fruit: </label>  <%= f.select(:IST_FRUIT, [['Apple', 'Apple'],
                          ['Orange', 'Orange'],
                          ['Kiwi', 'Kiwi'],
                          ['Other', 'Other']
                          ],{ :prompt => "Please select"},{:onchange => "if (this.value == 'Other') 
                                                                         {document.getElementById('otherTissue').style.display = 'block';
                                                                         } "}
                          ) %>

<span id="otherFruit" style="display:none;"> If other, please state: <%= f.text_field :IST_FRUIT, :size => 10  %></span>

User can select a fruit form the listbox but if user selects ‘Other’, a textfield is diaplayed allowing user to input his value.

The problem is that when user selects a fruit and save the form, the fruit field in blank in the table and the reason is that the form is saving the second field ‘IST_FRUIT’ found in the span with id ‘IST_FRUIT’.

I would be really grateful if someone could show me a way how to disable the second field when ‘other’ is not selected and enable it when ‘Other’ is selected from the dropdown list.

Many many thanks for any suggestion provided.

Answer 1

First, be aware that rails posts are based on fields’ name, not ids.

In your case, you should use a virtual attribute to store the potential other fruit value.

Your model could look like:

attr_accessor :other_fruit

before_save :check_fruits

def check_fruits
  #if other_fruit is not nil, it means that you want to store it's value in you IST_FRUIT column 
  #BTW, why these capital letters?
  IST_FRUIT = other_fruit unless other_fruit.nil?
end

And your form would be:

<span id="otherFruit" style="display:none;"> If other, please state: <%= f.text_field :other_fruit, :size => 10  %></span>