数组中的collection_radio_buttons

Question

如何使用collection_radio_buttons?从模型中的预定义集合中选择值

我试过了

= f.collection_radio_buttons :lang_lvl, Language.language_levels, :language_level, :language_level #does not work
= f.select :lang_lvl, Language.language_levels, include_blank: true #works

数据源在模型Language.rb中定义：

class Languages < ActiveRecord::Base
  LANGUAGE_LEVELS = [:"A1/Elem", :"A2/PreInt", :"B1/Int", :"B2/UpperInt", :"C1/Adv", :"C2/Prof", :"A1/Beg"]

  def self.language_levels
    LANGUAGE_LEVELS.map { |language_level| [language_level, language_level] }
  end
end

Answer 1

collection_radio_buttons的第三个和第四个参数分别指定了用于提取值和文本的方法。该函数将尝试调用[language_level, language_level].language_level来转换数据，因为您将数组数组作为集合传递，并为该子数组中的每个项调用:language_level。

如果不想更改模型，可以尝试将代码更改为：

= f.collection_radio_buttons :lang_lvl, Language.language_levels, :first, :last