提交以前的表单时如何生成新的rails表单

Question

我正在制作一个允许用户创建食谱的 Rails 应用程序。在新的食谱页面上，有食谱标题、作者等的输入字段，然后是成分的输入字段。创建新成分后，页面将重定向到“显示配方”页面。页面如何动态生成新的成分表，低于旧的成分表。

ingredients_controller.rb

class IngredientsController < ApplicationController

  def create
    @recipe = Recipe.find(params[:recipe_id])
    @ingredient = @recipe.ingredients.create(ingredient_params)
    redirect_to new_recipe_path(@recipe)
  end

  private
  def ingredient_params
    params.require(:ingredient).permit(:name, :amount, :uom)
  end
end

recipes_controller.rb

class RecipesController < ApplicationController
  def index
    @recipes = Recipe.all
  end

  def show
    @recipe = Recipe.find(params[:id])
  end

  def new
    @recipe = Recipe.new
    @recipe.ingredients.build
  end

  def edit
    @recipe = Recipe.find(params[:id])
    @recipe.ingredients.build
  end

  def create
    @recipe = Recipe.new(recipe_params)
    if @recipe.save
      redirect_to @recipe
    else
      render 'new'
    end
  end

  def update
    @recipe = Recipe.find(params[:id])

    if @recipe.update(recipe_params)
      redirect_to @recipe
    else
      render 'edit'
    end
  end

  def destroy
    @recipe = Recipe.find(params[:id])
    @recipe.destroy

    redirect_to @recipe
  end

  private
  def recipe_params
    params.require(:recipe).permit(:title, :author, :note,
                                   ingredients_attributes: [:id, :name, :amount, :uom])
  end
end

我的表单被分成两部分，一份用于配方表单标题 _form.html.rb，另一份名为 _ingform.html.rb，_ingform.html.rb 在 _form.html.rb 和 _form.html.rb 中呈现在 new.html.rb 和 edit.html.rb 中呈现。

_form.html.rb

<link rel="stylesheet" type="text/css" href="app/assets/stylesheets/form.css">

<div id = "form">
  <%= form_for(@recipe) do |form| %>
    <% if @recipe.errors.any? %>
      <div id = "error_explanation">
        <h2>
          <%= pluralize(@recipe.errors.count, "error") %>
          prohibited this recipe from being saved:
        </h2>
        <ul>
          <%@recipe.errors.full_messages.each do |msg| %>
            <li><%= msg %></li>
          <% end %>
        </ul>
      </div>
    <% end %>

    <p>
      <%= form.label :title  %><br>
      <%= form.text_field :title %>
    </p>

    <p>
      <%= form.label :author  %><br>
      <%= form.text_field :author %>
    </p>

    <p>
      <%= form.label :note %><br>
      <%= form.text_area :note %>
    </p>

      <%= render 'ingform' %>

      <p>
        <%= form.submit %>
      </p>

  <% end %>
</div>

_ingform.html.rb

<link rel="stylesheet" type="text/css" href="app/assets/stylesheets/ingform.css">
<%= form_for(@recipe) do |form| %>
  <h2>Add an Ingredient: </h2>
  <%= form.fields_for :ingredients do |new| %>
    <p class = "input_field">
      <%= new.label :name, "name" %><br>
      <%= new.text_field :name %>
    </p>
    <p class = "input_field">
      <%= new.label :amount, "amount" %><br>
      <%= new.number_field :amount %>
    </p>
    <p class = "input_field">
      <%= new.label :uom, "UOM" %><br>
      <%= new.text_field :uom %>
    </p>
    <p class = "input_field">
      <%= new.submit %>
    </p> </br>
  <% end %>
<% end  %>

配料属于食谱。 食谱.rb

class Recipe < ApplicationRecord
  has_many :ingredients, :dependent => :delete_all
  accepts_nested_attributes_for :ingredients, reject_if: :all_blank
  validates :title, presence: true, length: {minimum: 4}
  validates :author, presence: true
end

谢谢

Answer 1

这是一个常见问题 - 都是关于嵌套形式的：最简单的选择是确保您的配方 accepts nested attributes for 成分。请注意this following railscast：实际上实现起来很容易。唯一的问题是表单是一次性提交的。