我正在构建一个应用程序,用户可以从一系列营养素中进行选择,以在他的个人食物日记中添加一些。因此,我创建了一个user_nutrients表,其中包含用户必须输入的user_id,nutrient_id和其他信息。将数据以正确的方式存储在Rails中
在列表中的每个营养项目旁边,我都有一个按钮(“添加此项”),用于将用户重定向到我的user_nutrients_controller.rb
的新动作。到现在为止还挺好。
我现在研究了几天,但没有找到适合我的问题的解决方案:我必须在我的代码中更改什么,以便在user_nutrients/new.html.erb
用户不必手动输入nutrient_id
,但它自动保存用户在nutrients/index.html.erb
列表中选择的营养素的ID(通过“添加此”按钮)?每个用户has_many :user_nutrients
和has_many :nutrients, through: :user_nutrients
。每种营养物质has_many :user_nutrients
和has_many :users, through: :user_nutrients
。
非常感谢。
对不起,如果这个问题太简单或不能完全理解。刚刚开始编码几周前。
营养物/ index.html.erb
<% @nutrients.each do |nutrient| %>
<tr>
<td><%= nutrient.id %></td>
<td><%= link_to nutrient.name, nutrient, class: "link" %></td>
<td class="hidden-xs"><%= nutrient.kcal %></td>
<td class="hidden-xs"><%= nutrient.fat %></td>
<td class="hidden-xs"><%= nutrient.carbs %></td>
<td class="hidden-xs"><%= nutrient.sugar %></td>
<td class="hidden-xs"><%= nutrient.protein %></td>
<td class="hidden-xs"><%= nutrient.gram %></td>
<td class="hidden-xs"><%= nutrient.points %></td>
<td>
<div class="dropdown">
<button class="btn btn-default dropdown-toggle btn-xs" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
Actions
<span class="caret"></span>
</button>
<ul class="dropdown-menu dropdown-menu-right" aria-labelledby="dropdownMenu1">
<li><%= link_to 'Edit', edit_nutrient_path(nutrient) %></li>
<li role="separator" class="divider"></li>
<li><%= link_to 'Add this', new_user_nutrient_path %></li>
<li role="separator" class="divider"></li>
<li><%= link_to 'Delete', nutrient_path(nutrient), method: :delete, data: {confirm: "Are you sure?"} %></li>
user_nutrients_controller.rb
class UserNutrientsController < ApplicationController
before_action :set_user_nutrient, only: [:show, :edit, :update, :destroy]
# GET /user_nutrients
# GET /user_nutrients.json
def index
@user_nutrients = UserNutrient.where(:user_id => current_user.id).order(day: :desc)
end
# GET /user_nutrients/1
# GET /user_nutrients/1.json
def show
end
# GET /user_nutrients/new
def new
@user_nutrient = UserNutrient.new
end
# GET /user_nutrients/1/edit
def edit
end
# POST /user_nutrients
# POST /user_nutrients.json
def create
@user_nutrient = UserNutrient.new(user_nutrient_params)
@user_nutrient.user = current_user
respond_to do |format|
if @user_nutrient.save
format.html { redirect_to user_nutrients_path, notice: 'User nutrient was successfully created.' }
format.json { render :show, status: :created, location: @user_nutrient }
else
format.html { render :new }
format.json { render json: @user_nutrient.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /user_nutrients/1
# PATCH/PUT /user_nutrients/1.json
def update
respond_to do |format|
if @user_nutrient.update(user_nutrient_params)
format.html { redirect_to @user_nutrient, notice: 'User nutrient was successfully updated.' }
format.json { render :show, status: :ok, location: @user_nutrient }
else
format.html { render :edit }
format.json { render json: @user_nutrient.errors, status: :unprocessable_entity }
end
end
end
# DELETE /user_nutrients/1
# DELETE /user_nutrients/1.json
def destroy
@user_nutrient.destroy
respond_to do |format|
format.html { redirect_to user_nutrients_url, notice: 'User nutrient was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_user_nutrient
@user_nutrient = UserNutrient.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def user_nutrient_params
params.require(:user_nutrient).permit(:user_id, :nutrient_id, :amount, :day)
end
end
_form.html.erb(用于用户营养素)
<%= form_for(@user_nutrient) do |f| %>
<% if @user_nutrient.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(@user_nutrient.errors.count, "error") %> prohibited this user_nutrient from being saved:</h2>
<ul>
<% @user_nutrient.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :nutrient_id %><br>
<%= f.number_field :nutrient_id %>
</div>
<div class="field">
<%= f.label :amount %><br>
<%= f.number_field :amount %>
</div>
<div class="field">
<%= f.label :day %><br>
<%= f.date_select :day %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
这太棒了!这样的救济。我正在为此研究日子!多谢! – Oliver