[RUBY] [Rails] Volume that displays favorites and a list of favorites

Introduction

If you find a product that you think is good for online shopping, have you registered it as a favorite? At that time, if the screen is not updated and you like it or like it, the color of the ♡ mark will change. After that, it would be nice if you could check your favorite products in a list. This time is a memo of the implementation.

• We will proceed on the assumption that the listing and posting functions (items table) and login function (users table) are provided.

Implementation procedure (synchronous edition)

When you click on the completed image, a part of the screen is updated and the number count increases. It also has a delete function. We will also create a page where you can check what you have added to your favorites in a list.

First, as an intermediate table between the items table and the users table Create a likes table.

↓ The columns to be added and the association look like this ↓

items table

=== Abbreviation ===

• No addition * Association

• has_many :likes --has_many: liked_users, through :: likes, source:: user # Use when you want to make a favorite list, but do not use this time

likes table #intermediate table

Association

• belongs_to :item
• belongs_to :user

users table

=== Abbreviation ===

• No addition *

Association

• has_many :likes --has_many: liked_items, through:: likes, source:: item # Use when you want to make a favorite list, but do not use this time

This completes the DB design Next, create a model. Enter the following command in the terminal

rails g model like

Edit migration file to create table

2XXXXXXXXXXXX5_create_likes.rb

class CreateLikes < ActiveRecord::Migration[5.2]
  def change
    create_table :likes do |t|
      t.integer :item_id, null: false
      t.integer :user_id, null: false
    end
  end
end

Rails from db: migrate. Then a model will be generated, so we will write the association.

user.rb

has_many :likes #add to

item.ruby

has_many :likes #add to

like.rb

class Like < ApplicationRecord

  belongs_to :item
  belongs_to :user

  validates :user_id, presence: true
  validates :item_id, presence: true
  validates_uniqueness_of :item_id, scope: :user_id

  def self.like_method(item, user)
    Like.find_by(item_id: item.id, user_id: user.id)
  end

end

self.like_method(item, user) I will set the IF statement here. Set the condition that item_id and user_id are in the like table! Then run the following command to create the controller

rails g controller likes

Once the controller is created successfully ・ View file ·controller ·routing I will set each.

routes.rb

--Omitted ---
resources :items, only: [:new, :create, :edit, :update, :show, :destroy] do
    resources :likes, only: [:create, :destroy]
  end
--Omitted ---
  resources :users, only: [:show] do
    resources :likes, only: [:index]
  end
--Omitted ---

create and destroy are nested in items index nested in users

likes_controller.rb

class LikesController < ApplicationController

  before_action :set_item, only: [:create, :destroy]

  def index
    @items = Item.includes(:item_images).order("created_at DESC")
  end

  def create
    @like = Like.create(item_id: params[:item_id],user_id: current_user.id)
    redirect_to item_path(@item.id)
  end

  def destroy
    @like = Like.find_by(item_id: params[:item_id],user_id: current_user.id)
    @like.destroy
    redirect_to item_path(@item.id)
  end

  def set_item
    @item = Item.find(params[:item_id])
  end

end

Since create and destroy do not have a view file, you need to set redirects.

index.html.haml

--Omitted ---
      - if user_signed_in? && Like.like_method(@item, current_user)
        .check_btn__like--add{data: {item_id: @item.id}}
          = link_to "/items/#{@item.id}/likes/:id" , method: :DELETE do
            = icon( "fa", "star")
favorite
            = @item.likes.length
      - elsif user_signed_in?
        .check_btn__like{data: {item_id: @item.id}}
          = link_to "/items/#{@item.id}/likes", method: :POST do
            = icon( "fa", "star")
favorite
            = @item.likes.length
      - else
        .check_btn__like
          = link_to new_user_session_path do
            = icon( "fa", "star")
favorite
            = @item.likes.length
--Omitted ---

Click here for the screen when registering as a favorite

index.html.haml

.mypage_Wrapper
  %section.mypage_title
Favorite list
  %section.like_Wrapper
    .like__box
      - @items.each do |item|
        - if user_signed_in? && Like.like_method(item, current_user)
          .like__box__product
            .like__image
              = link_to item_path(item.id) do
                = image_tag item.item_images[0].image.url
            .like__name
              = item.name
            %ul
              %li
                = item.price.to_s
              %li
                = "Circle"
              %li.like__tax
                = "(tax included)"
              %li.like__icon
                = link_to "/items/#{item.id}/likes/:id" , method: :DELETE do
                  = icon("fas", "star")
.bottom_Wrapper

This is what you see in your favorite product list

like.scss

.like_Wrapper {
  width: 100%;
}

.like__box {
  background-color:white;
  margin: 0 auto;
  width: 65%;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  &__product {
    width: 180px;
    height: 90%;
    margin: 25px 2% 0;
    transition: all .3s ease-in-out;
    .like__image {
      width: 180px;
      height: 140px;
      margin-bottom: 3%;
      img{
        width: 100%;
        height: 100%;
        object-fit: cover;
      }
    }
    .like__name {
      font-weight: bold;
    }
    ul{
      display: flex;
      font-size: 16px;
      li{
        font-weight: bold;
      }
      .like__tax {
        font-size: 10px;
        writing-mode: lr-tb;
        width: 30px;
        line-height: 30px;
        margin-left: 2%;
        margin-right: 24%;
      }
      .like__icon {
        i {
          font-size:1.1em;
          color: orange;
        }
      }
    }
  }
  &__product:hover {
    cursor: pointer;
    transform: scale(1.1, 1.1);
  }
}

For the time being, CSS I think that it can be implemented in a synchronized state with the implementation so far! So far, if you implement asynchronous communication using Ajax, it will be richer, so I wish I could write that ... It will be later ...

reference

https://techtechmedia.com/favorite-function-rails/#i https://qiita.com/naberina/items/c6b5c8d7756cb882fb20 https://qiita.com/hisamura333/items/e3ea6ae549eb09b7efb9 https://qiita.com/shh-nkmr/items/48fe53282253d682ecb0