ruby-on-rails – 带有has_many的Rails复杂视图表单：通过关联

class Recipe < ActiveRecord::Base
    has_many :ingredients
    has_many :items,:through => :ingredients
end

class Item < ActiveRecord::Base
    has_many :ingredients
    has_many :recipes,:through => :ingredients
end

class Ingredient < ActiveRecord::Base
    # Has extra attribute :quantity
    belongs_to :recipe
    belongs_to :item
end

此关联在控制台中有效.例如：

Recipe.create( :name => 'Quick Salmon' )
Item.create( :name => 'salmon',:unit => 'cups' )
Ingredient.create( :recipe_id => 1,:item_id => 1,:quantity => 3)

Recipe.first.ingredients
=> [#<Ingredient id: 1,recipe_id: 1,item_id: 1,quantity: 3]

Recipe.first.items
=> [#<Item id: 1,name: "salmon",unit: "cups"]

但是,我不明白如何创建新的配方视图,以便我可以在一个页面中将配料直接添加到配方中.我是否需要使用fields_for或嵌套属性？如何构建视图表单和控制器逻辑以在一个页面中创建具有成分的配方？

我在Rails 3.1.3上.