Question

I want to create a nested multi select in formtastic from two objects like this –

Option 1
   Option A
   Option B
   Option C
Option 2
   Option A
   Option B
   Option C

list1 = ['option1', 'option2']
list2 = ['Option A', 'Option B', 'Option C']

Is this possible with formtastic or is it better to use a helper to format the data ?

Thanks, Alex

Answer 1

It’s possible, you have to use something like:

<%= f.input :input_field_name, :as => :select, :collection => grouped_options_for_select(['List 1', list1], ['List 2', list2]) %>

Look up the Formtastic documentation for input_select and the Rails API for grouped_options_for_select for other possible formatting options.