app/inputs/ajax_select_input.rb
class AjaxSelectInput < SimpleForm::Inputs::CollectionSelectInput
delegate :content_tag, :concat, :javascript_additional_packs, to: :template
def input(wrapper_options = {})
label_method, value_method = detect_collection_methods
merged_input_options = merge_wrapper_options(input_html_options, {})
javascript_additional_packs 'inputs/ajax_select'
@builder.collection_select(
attribute_name, collection, value_method, label_method,
input_options, merged_input_options
)
end
end