# controller
def index
#teams = TeamMember.where(user: current_user)
end
# view
<%= #teams.each do |t| %>
<h2><%= t.project.name %></h2>
<p>Where's the line below this coming from?</p>
<!-- what's happening here? -->
<% end %>
The result in the browser looks as follows. It returns #projects as a string. Where is this coming from and how do I remove it?
ERB
You trigger ERB by using embeddings such as <% %>, <% -%>, and <%= %>. The <%= %> tag set is used when you want output.
You have used <%= %> for looping projects and the block form of Array#each returns the original Array object, which is why it prints the projects result at the end.
you have to use <% %> for #projects.each do |p| instead of <%= %>
# view
<% #projects.each do |p| %>
<h2><%= p.name %></h2>
<% end %>
Team member Model
class TeamMember < ApplicationRecord
belongs_to :user
belongs_to :project
end
User Model
class User < ApplicationRecord
has_many :team_members
end
Project Model
class Project < ApplicationRecord
has_many :team_members
end
Controller
def index
#teams = current_user.team_members
end
View
<% #teams.each do |t| %> // Remove '=' from the loop itereation
<h2> <%= t.project.name %> </h2>
<% end %>
Related
I'm fairly new to ruby on rails and this has been kind of an interesting problem since this seems easy to implement in other languages but I don't know how to tackle it in this one. There was a similar post to this but it had two separate models which I would like to avoid.
This is my end goal:
Section Name
Book A, author
Book B, author
Section Name
Book C, author
Book D, author
Ideally, I'd like to have books be one model, so my model looks like this:
Book Model
class Book < ApplicationRecord
validates :section, :title, :author, presence: true
Book Controller
def index
#books = Book.all
I'm assuming I would need some sort of view that has it list it like below but I'm not sure how to go from there.
<% #sections.each do |section| %>
<% Book.each do |book| %>
<%= book.name %>
<% end %>
<% end %>
Any help would be very appreciated!
Firstly you need migration and associations between these models
change_table :books do |t|
t.belongs_to :section, foreign_key: true, null: false
end
class Book < ApplicationRecord
belongs_to :section
class Section < ApplicationRecord
has_many :books, dependent: :destroy
And in view you can iterate through sections and separately through evert section books
<% #sections.each do |section| %>
<div><b><%= section.name %></b></div>
<ul>
<% section.books.each do |book| %>
<li>
<%= book.name %>, <%= book.author %>
</li>
<% end %>
</ul>
<% end %>
what you need is this:
<% #sections.each do |section| %>
<% section.books.each do |book| %>
<%= book.name %>
<% end %>
<% end %>
tl, dr: Is it possible to populate a ternary association with accepts_nested_attributes and consequently pass the tests from this PR?
Basically I created four models A, B, C and Abc and the latter is a join table for a ternary association with the other models. The problem is using accepts_nested_attributes_for I can't seem to save the whole ternary association. Instead I either create two join models with binary associations (A-B, B-C or A-C) or the database complains about missing foreign keys. Checkout this test and the code:
class A < ApplicationRecord
has_and_belongs_to_many :bs, join_table: :abcs
has_and_belongs_to_many :cs, join_table: :abcs
accepts_nested_attributes_for :bs, :cs
end
class B < ApplicationRecord; end
class C < ApplicationRecord; end
class Abc < ApplicationRecord
belongs_to :a
belongs_to :b
belongs_to :c
end
class AsController < ApplicationController
def new
#a = A.new
#a.bs.build
#a.cs.build
end
def create
#a = A.new(a_params)
if #a.save
redirect_to(new_a_path)
else
render(:new)
end
end
def a_params
params.require(:a).permit(:name, bs_attributes: [:name], cs_attributes: [:name])
end
end
<%= form_for(#a) do |f| %>
<% if #a.errors.any? %>
<ul>
<% #a.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
<% end %>
<%= f.label(:name) %>
<%= f.text_field(:name) %>
<ul>
BS:
<%= f.fields_for(:bs) do |ff| %>
<li>
<%= ff.label(:name) %>
<%= ff.text_field(:name) %>
</li>
<% end %>
</ul>
<ul>
CS:
<%= f.fields_for(:cs) do |ff| %>
<li>
<%= ff.label(:name) %>
<%= ff.text_field(:name) %>
</li>
<% end %>
</ul>
<%= f.submit %>
<% end %>
I've also tried creating it from the ternary table which works for one single association among the models (A-B-C), but it's impossible for multiple (A1-B1-C1, A1-B2-C1). Check out the code:
class AsController < ApplicationController
def new
#abc = Abc.new
#abc.build_a
#abc.build_b # 2.times { #abc.build_b } only overwrites #abc.b
#abc.build_c
end
end
It seems no matter what Rails can only create associations between two models leaving the ternary model missing one association.
I have isolated the issue as a repository's pull request as you can see HERE
I think I'm supposed to use polymorphic for this, but when I tried the code I could find to solve it, it didn't work.
In plain English, I am creating a Message, and I want it to
1) either belong_to a Guide or a Member
2) has_one Trip or Bid
I get a rollback error when I try and save a new Message and when I try and reference the "first_name" of a Guide in a View via a message I get the following error:
undefined method `guide' for #<Message:0x0000000487bd48>
Did you mean? guide_id
These are my models:
class Guide < ApplicationRecord
has_many :messages, as: :messageable
end
class Member < ApplicationRecord
has_many :messages, as: :messageable
end
class Message < ApplicationRecord
belongs_to :messageable, polymorphic: true
has_one :bid or :trip
end
This is the code snippet for showing the first_name, for what it's worth the text of the message msg.message displays just fine.
<% if #bid.messages.present? %>
<% #bid.messages.each do |msg| %>
<p>From:
<% if msg.guide_id.present? %>
<%= msg.guide.first_name %>
<% elsif msg.member.present? %>
<%= msg.member.first_name %>
<% end %>
</p>
<p>Message: <%= msg.message %></p>
<% end %>
<% else %>
<p>No messages</p>
<% end %>
You always keep referencing the polymorphic name, so instead of doing msg.guide.first_name, you use: msg.messageable.first_name
It might be worth to share your database migration as well. In the code you are checking for: guest_id, which shouldn't be part of the Message model. There should only be an attribute called messagable_id, so the view can be simplified:
<% if #bid.messages.present? %>
<% #bid.messages.each do |msg| %>
<p>From: <%= msg.messageable.first_name %></p>
<p>Message: <%= msg.message %></p>
<% end %>
<% else %>
<p>No messages</p>
<% end %>
I have a nested relationship where dashboard has many rewards, and I am trying to add a fields_for to the page in order to edit the rewards. Unfortunately, it doesn't seem to be working and I don't know why.
Here's what I have.
Dashboard model:
class Dashboard < ActiveRecord::Base
belongs_to :manager
has_many :rewards
accepts_nested_attributes_for :rewards, allow_destroy: true
end
Rewards model:
class Reward < ActiveRecord::Base
belongs_to :dashboard
end
Dashboard controller:
class DashboardsController < ApplicationController
before_action :authenticate_manager!
# Requires user to be signed in
def index
#dashboards = Dashboard.all
end
def new
#dashboard = Dashboard.new
end
def edit
#dashboard = Dashboard.find(params[:id])
end
def create
#dashboard = Dashboard.new(dashboard_params)
#dashboard.save
if #dashboard.save
redirect_to dashboard_path(#dashboard)
else
render :action => new
end
end
def update
#dashboard = Dashboard.find(params[:id])
if #dashboard.update(dashboard_params)
redirect_to :action => :show
else
render 'edit'
end
end
def show
#dashboard = Dashboard.find(params[:id])
end
def destroy
#dashboard = Dashboard.find_by_id(params[:id])
if #dashboard.destroy
redirect_to dashboards_path
end
end
private
def dashboard_params
args = params.require(:dashboard).permit(:title, :description, :rewards, {rewards_attributes: [ :id, :title, :referralAmount, :dashboardid, :selected, :_destroy] } )
args
end
end
Form in dashboards view:
<%= form_for :dashboard, url: dashboard_path(#dashboard), method: :patch do |f| %>
<% if #dashboard.errors.any? %>
<div id="error_explanation">
<h2>
<%= pluralize(#dashboard.errors.count, "error") %> prohibited
this dashboard from being saved:
</h2>
<ul>
<% #dashboard.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<p>
<%= f.label :title %><br>
<%= f.text_field :title %>
</p>
<p>
<%= f.label :description %><br>
<%= f.text_field :description %>
</p>
<%= f.fields_for :rewards do |reward| %>
<%= reward.label :title %><br>
<%= reward.text_field :title %>
<%= reward.check_box :_destroy %>
<%= reward.label :_destroy, "Remove reward" %>
<% end %>
<p>
<%= f.submit %>
</p>
<% end %>
I went ahead and manually added rewards to the database through the rails console and it worked beautifully, but they are not showing up on the page. They will show up if I iterate through them like so
<% if #dashboard.rewards.any? %>
<ul>
<% #dashboard.rewards.each do |reward| %>
<li><%= reward.title %></li>
<li><%= reward.referralAmount %></li>
<% end %>
</ul>
<% else %>
<p>no rewards</p>
<% end %>
However the fields_for does not display the rewards or their content and resultingly allow one to edit them.
Let me know if you need further information/code.
Try to modify your:
View:
<% if #dashboard.errors.any? %>
<div id="error_explanation">
<h2>
<%= pluralize(#dashboard.errors.count, "error") %> prohibited
this dashboard from being saved:
</h2>
<ul>
<% #dashboard.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<%= form_for #dashboard, url: dashboard_path(#dashboard) do |f| %>
........
<% end %>
Controller (has_many relationship):
def new
#dashboard = Dashboard.new
#dashboard.rewards.build
end
private
def dashboard_params
params.require(:dashboard).permit(:title, :description,
rewards_attributes: [
:id,
:title,
:referralAmount,
:dashboardid,
:selected,
:_destroy
])
end
You don't have to set the method: patch if form.
Once you got in edit page, Rails will use the update action in controller when form submission.
To check it, run rake routes,
you will see somsthing like this:
PATCH /dashboards/:id(.:format) dashboards#update
PUT /dashboards/:id(.:format) dashboards#update
In controller you need to give build
def new
#dashboard = Dashboard.new
#dashboard.rewards.build
end
"build" is just create a new object in memory so that the view can take this object and display something, especially for a form.
Hope it helps for you
You should build object before nested form. You can add whatever you want that object.
Try it in controller;
def new
#dashboard = Dashboard.new
3.times do
#dashboard.build_reward
end
end
Try setting an "#rewards" instance variable in your dashboards edit method (where #rewards = #dashboard.rewards). Then replace :rewards with #rewards.
Edit:
I believe my initial answer is inapproriate for your exact question (while it would be helpful on say the page to show a specific dashboard and its rewards). The answers above are on the right track re:
refining your params method per #aldrien.h;
Adding #santosh dadi's suggestion of
#dashboard.rewards.build
(assuming you only want one rewards fields on a form for "new")
Finally though, to avoid making fake information for a new rewards form, adding to the top of your Dashboards model:
accepts_nested_attributes_for :rewards, reject_if: lambda {|attributes| attributes['title'].blank?}
http://guides.rubyonrails.org/form_helpers.html#nested-forms
I would like to reference images in buildings/index.html.erb. I have:
class BuildingsController < ApplicationController
def index
#buildings = Building.all
#images = #buildings.images.all
end
end
class Building < ActiveRecord::Base
has_many :images
end
class Image < ActiveRecord::Base
belongs_to :building
end
buildings/index.html.erb:
<% #buildings.each do |building| %>
<% if #buildings.images.any? %>
<% #buildings.images.name %>
<% end %>
<% end %>
I get the following error: undefined method images for <Array:0x000001109b4680>
#buildings is an array of Building objects. Every Building object has its images method. You might iterate over the #buildings array and call the images method of every member.
<% #buildings.each do |building| %>
This is Building with ID <%= building.id %>.
<% if building.images.any? %>
...
<% end %>
<% end %>
Also, you don't need the #images variable in your controller.
You're not iterating over your buildings. You need to grab each one and then do what you were trying to do:
<%- #buildings.each do |building| %>
<%- if building.images.any? %>
...
<%- end %>
<%- end %>
You can also do:
index.html.erb
<%= render #buildings %>
This will take each Building object and pass it to a _building.html.erb partial where you can then do
_building.html.erb
<%- if building.images.any? %>
...
<%- end %>