I don't have an image of how to use it, which somehow understands the meaning. I decided to write an article for the reason of
Used in form_for and form_with Image of sending invisible values
Apparently there is also a "hidden_field_tag" helper These differences will be posted on another day
Create a screen for users to post Before posting, try creating a ** confirmation screen for the content of the post **
User and Post controllers and models Try to create
~/environment/rails/sample_app
❯ rails g controller users
~/environment/rails/sample_app
❯ rails g model User
~/environment/rails/sample_app
❯ rails g controller posts index new create
~/environment/rails/sample_app
❯ rails g model Post
~/environment/rails/sample_app
❯ rails db:migrate
app/model/user.rb
class User < ApplicationRecord
has_many :posts
end
app/model/post.rb
class User < ApplicationRecord
has_many :user
end
While looking at the article I wrote before Enter the initial data of User and Post Article to put the initial data written before
db/seeds.rb
test_user = User.create!(
name: 'test',
email: '[email protected]',
password: 'password'
)
Post.create!(
title: 'test title',
contents: 'Post test',
user_id: test_user.id
)
Post.create!(
title: 'test title2',
contents: 'Post test, second time',
user_id: test_user.id
)
Execute with the following command
rails db:seed
Description of controller Declaring user acquisition over and over is a hassle Describe with private method
app/controller/posts_controller.rb
class PostsController < ApplicationController
before_action :set_user
def index
@posts = Post.where(user_id: @user.id)
end
private
def set_user
@user = User.find(1)
end
end
Create view
rb:app/views/posts/index.html.erb
<h1>Post list screen</h1>
<% @posts.each do |post| %>
<p><%= post.title %></p>
<p><%= post.contents %></p>
<% end %>
Routing definition
config/routes.rb
Rails.application.routes.draw do
get 'posts/index'
end
This is also from the description of the controller
app/controller/posts_controller.rb
class PostsController < ApplicationController
before_action :set_user
def index
@posts = Post.where(user_id: @user.id)
end
def new
@posts = Post.new
end
def create
@posts = Post.create(
title: params[:post][:title],
contents: params[:post][:contents],
user_id: @user.id
)
if @posts.save
redirect_to posts_index_path
else
render :new
end
end
private
def set_user
@user = User.find(1)
end
end
Stumble trying to get as "params [: title]"
Check parameters
Get with ** params [: model name] [: passed name attribute] **
Create view
rb:app/views/posts/new.html.erb
<h1>Post new creation screen</h1>
<%= form_with(model: @posts, url: posts_create_path, local: true) do |f| %>
<div id="container">
<%= f.text_field :title %>
<%= f.text_area :contents %>
<%= f.submit %>
</div>
<% end %>
Routing definition
config/routes.rb
Rails.application.routes.draw do
get 'posts/index'
#add to
get 'posts/new'
post 'posts/create'
end
With this, first of all, ordinary users post I was able to reach the list screen
Add "** confirm action **" for confirm screen to Post controller
app/controller/posts_controller.rb
class PostsController < ApplicationController
before_action :set_user
#add to
before_action :posts_params
def index
@posts = Post.where(user_id: @user.id)
end
def new
@posts = Post.new
end
#Added action for confirmation screen
def confirm
@posts = Post.new(
title: params[:post][:title],
contents: params[:post][:contents]
)
#Returns true if an error occurs, false if there is no error
if @posts.valid?
render :confirm
else
render :new
end
end
#Delete
def create
@posts = Post.create(
title: params[:post][:title],
contents: params[:post][:contents],
user_id: @user.id
)
if @posts.save
redirect_to posts_index_path
else
render :new
end
end
private
def set_user
@user = User.find(1)
end
#Strong parameter added
def posts_params
params.require(:post).permit(:title, :contents)
end
end
There seems to be a difference here as well
「valid?」 The result of validation Returns true ** if there are no errors **, false ** if an error occurs
"** invalid? **" is the opposite
From the definition of routing
config/routes.rb
Rails.application.routes.draw do
get 'posts/index'
get 'posts/new'
#Delete
post 'posts/create'
#add to
post 'posts/confirm'
end
view creation
~/environment/rails/sample_app
❯ touch app/views/posts/confirm.html.erb
Modify the view But first I want to test if I go to the confirmation screen
rb:app/views/posts/confirm.html.erb
<h1>success</h1>
Just fill in
When I submitted the form, the URL was
It says localhost: 3000/posts/confirm
OK if the "Success" screen appears on the screen
Add an action
app/controller/posts_controller.rb
class PostsController < ApplicationController
# ~Omitted~
#Action for confirmation screen
def confirm
@posts = Post.new(
title: params[:post][:title],
contents: params[:post][:contents]
)
#Returns true if an error occurs, false if there is no error
#Described by postfix if
render :confirm if @posts.valid?
end
# ~Omitted~
end
Create a view
rb:app/views/posts/confirm.html.erb
<h1>confirmation screen</h1>
<%= form_with(model: @posts, url: posts_complete_path, local: true) do |f| %>
<div id="container">
#Appeared here, "hidden_field」
<%= f.hidden_field :title %>
<%= @posts.title%>
<%= f.hidden_field :contents %>
<%= @posts.contents%>
#Name attribute that allows you to name the parameter
<%= f.submit 'Return', name: 'back' %>
<%= f.submit 'Send' %>
</div>
<% end %>
A little trouble with the destination of the form -Form_with is sent by "POST" by default -When you create an object using create in the controller, new and save Will go → Therefore, the form is submitted as "PATCH" → "PATCH" is sent when there is already an object
Add an action for the ** completion screen **
app/controller/posts_controller.rb
class PostsController < ApplicationController
# ~Omitted~
#Action for confirmation screen
def confirm
@posts = Post.new(
title: params[:post][:title],
contents: params[:post][:contents]
)
#Returns true if an error occurs, false if there is no error
#Described by postfix if
render :confirm if @posts.valid?
end
#Action for completion screen
def complete
@posts = Post.new(
title: params[:post][:title],
contents: params[:post][:contents],
user_id: @user.id
)
#To parameters[:back]Is attached(back button)Click
#Or, if the object is not saved, return the "new" screen.
render :new if params[:back] || [email protected]
end
# ~Omitted~
end
With this, you can do the screen transition of ** Post → Confirm → Complete ** Completion of a simple posting application
Created view
rb:app/views/posts/confirm.html.erb
<h1>confirmation screen</h1>
<%= form_with(model: @posts, url: posts_complete_path, local: true) do |f| %>
<div id="container">
#Appeared here, "hidden_field」
<%= f.hidden_field :title %>
<%= @posts.title%>
HTML being created
<input type="text" name="post[title]" id="post_title">
Enter the content and press the back button
<input type="text" value="Test title" name="post[title]" id="post_title">
The entered value is included in" ** value ** "
Used when you want to pass a value without letting the user fill in directly from the form
https://railsguides.jp/action_view_overview.html https://railsdoc.com/page/hidden_field https://qiita.com/__xxx/items/7c9b194230c7ce2b02ca https://remonote.jp/rails-confirm-form https://web-begginer-log.com/rails-confirm/