在Rails的视图中调用模型函数引发错误

Question

Here is the model

class Admin::Filter < ActiveRecord::Base
    validates_uniqueness_of :name
    has_many :filter_values,class_name: "Admin::FilterValue",foreign_key: "admin_filter_id"
    enum field_type: [:select_tag,:select_tag_without_search,:check_box_tag]

    def underscore_filter_name
        if self.name.split.size > 1
            self.name.replace(self.name.scan(/[A-Z][a-z]*/).join("_"))
        else
            "#{self.name.downcase}_filter"
        end
    end

end

The function I am talking about is underscore_filter_name . Now I am calling this inside the rails console like this: Admin::Filter.first.underscore_filter_name which returns a value but when I try similarly inside the view it throws an error. Here is the view:

-@filters.each do |filter|
      %legend
        =filter.name
        -case filter.field_type
        -when "select_tag"
          = simple_form_for :"#{filter.underscore_field_name(filter)}",:url=> admin_requests_path,:method => "get",html: {:"data-filter"=>"#{filter.underscore_field_name}"}  do |f|
            = f.select("#{filter.name}", filter.filter_values.all.collect {|p| [ p.name, p.id ] }, {:include_blank => "Please select a #{filter.name}"},{:multiple => true,class: "form-control chosen-select select_tag_filter"})
        -when "select_tag_without_search"
          = select_tag "#{filter.name}", options_for_select(filter.filter_values.all.collect{ |u| [u.name, u.id]}), { :multiple => true,class: "search-free-chosen-select"}
        -when "check_box_tag"
          = simple_form_for :priority,:url=> admin_requests_path,:method => "get",html: {id: "priority_filter"}  do |f|
            = f.collection_check_boxes "#{filter.name}", filter.filter_values,:id,:name, :item_wrapper_class => 'inline'

The below line is the error I am getting:

undefined method `underscore_field_name' for #<Admin::Filter:0x007f07a322f068>

Why is this? I am using Rails 4.1

Answer 1

You've got in the view...

underscore_field_name

but the name of the method is

underscore_filter_name

Answer 2

You have defined underscore_filter_name as the method name and you have typed in the view as underscore_field_name . So is the error.

Change it to

= simple_form_for :"#{filter.underscore_filter_name(filter)}",:url=> admin_requests_path,:method => "get",html: {:"data-filter"=>"#{filter.underscore_field_name}"}  do |f|

This should resolve the error.