How to include a model inside my index view - ruby-on-rails

I have two model Event, and Photo with the following relationships:
Event
has_many :photos
accepts_nested_attributes_for :photos, :allow_destroy => true
Photo
belongs_to :event
When I create it in my Event#new controller I have the following
#event = Event.new
#event.photos.build
This is my Event#form view inside the form
<%= form_for(#event) do |f| %>
...
<%= fields_for :photos do |photo| %>
<%= photo.file_field :picture %>
<% end %>
<% end %>
And now I want to include the first photo because you may have more than one set related to this to show in Event#index.
I try this but it seem to fails:
<% #events.each do |event| %>
<% event.photos.first do |pict| %>
<%= pict.image... %>
<% end %>
<% end %>

Change <%= fields_for :photos do |photo| %> into <%= f.fields_for :photos do |photo| %>.
<% event.photos.first do |pict| %> is wrong - just get first picture and try accessing it (if it exists):
<% pict = event.photos.first %>
<% if pict %>
code here
<% end %>

You might need to add :multipart => true to your form_for block if you have a file field in the form. That could explain why it's not uploading.

I'm going to guess that it doesn't do anything because #first doesn't take a block. Try
<%= event.photos.first.image... %>
event.photos.first returns a single object, and passing a block (e.g. the do |photo| ... end part) to an object doesn't really do anything.
BTW, it would be helpful if you include a little more detail on what "it fails" means. Do you get a stack trace? Does nothing show on the page? Have you verified in the console that your Event object has one or more Photos?

Related

Rails, edit action does not populate the form correctly with many instances of the same model

I'm new to Rails and I'm doing my first project. Also, English is not my native language so bear with me, please.
The problem I'm having is that I have a form with multiple instances of the same model, the data is being created correctly but when I try to edit it the form is populated in the wrong way.
I'm making an app to check if everything goes according to the rules.
The items to be checked are in a nested association Chapters->Subchapters->Checks
Every time the checks are submitted a CheckRound is created and the information of every check is stored separately in CheckResults.
CheckRounds
has_many :check_results, inverse_of: :check_round, dependent: :destroy
accepts_nested_attributes_for :check_results, reject_if: proc { |att| att['observation'].blank? }
CheckResults
belongs_to :check_round, optional: true, inverse_of: :check_results
belongs_to :check
Chapters
has_many :subchapters
Subchapters
belongs_to: chapter
has_many: checks
Checks
belongs_to :subchapter
has_many :check_results
The form displays all the Chapters and the nested Subchapters and Checks.
Every Check displays its name and has a text_area as an input.
The user can fill none or many Checks.
<%= form_for(#check_round, :url => {:action => 'update', :client_id => #client.id, :project_id => #project.id}) do |f| %>
<% #chapters.each do |chapter| %>
<%= chapter.name %>
<% chapter.subchapters.each do |subchapter| %>
<%= subchapter.name %>
<% subchapter.checks.each do |check| %>
<%= f.fields_for :check_results do |result| %>
<%= check.name %>
<%= result.hidden_field(:check_id, :value => check.id) %>
<%= result.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s) %>
<% end %>
<% end %>
<% end %>
<% end %>
<% end %>
The controller is
def edit
#check_round = CheckRound.includes(:check_results).find(params[:id])
#chapters = Chapter.includes(subchapters: :checks).where("segment_id = ?", #project.segment_id).sorted
end
If for example, I submit that check.id = 3 has the observation = "bad" when I go to edit every check has "bad" in its observation regardless of its id.
I want to know how can I show in edit all the checks with a blank observation but the ones that were created.
Thanks in advance for your time!
Ok, From what i see 2 things that needs to fixed.
1st, your f.fields_for :check_results do |result|
needs an extra parameter to specify which check_results it exactly has to modify... somethings like this:
f.fields_for :check_results, #check_round.check_results.where(check_id: check.id) do |result|
in the exact same place so the check variable is specify the right way.
2de, you need to permit your nested parameters in your controller so they can be saved when u submit. Normally you should see a method called check_round_params in your check_round controller.
this one have to like this for everything to work:
def check_round_params
params.require(:check_round_params).permit(
/*your needed params*/,
check_results_attributes: [:id, :check_id, :observation, /*all your nested params*/]
)
end
In short, your update and your create actions work according to those permitted params, so you need define them there. check_results_attributes: is the way that rails understands those params are for nested models.
Here is some documentation you might find interesting:Nested attributes example
Here is the solution i've promised.
Sinds you have already defined that check results with blank observations had to be rejected and there will to much logic involved in your erb for its own sake, i would put it all in an helper method so your erb will be cleaner. Something like this:
#helpers/check_rounds_helper.rb
def edit_or_instantiate_nested_check_results(f, check_round, check, new_check_result)
if check.check_results
f.fields_for :check_results, check_round.check_results.where(check_id: check.id) do |result|
result.hidden_field(:check_id, :value => check.id)
result.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s)
end #end for the already present check results
# if u want to add a new check result event if the check is populated
f.fields_for :check_results, new_check_result do |new|
new.hidden_field(:check_id, :value => check.id)
new.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s)
end #end for the new check result
else #if there is no existing check result nest a form for a new one
f.fields_for :check_results, new_check_result do |new|
new.hidden_field(:check_id, :value => check.id)
new.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s)
end #end for the new check result
end #end if statement
end
Then in your view:
<%= form_for(#check_round, :url => {:action => 'update', :client_id => #client.id, :project_id => #project.id}) do |f| %>
<% #chapters.each do |chapter| %>
<%= chapter.name %>
<% chapter.subchapters.each do |subchapter| %>
<%= subchapter.name %>
<% subchapter.checks.each do |check| %>
<%= check.name %>
<% new_check_result = CheckResult.new(check_round_id: #check_round.id, check_id = check.id) %>
<%= edit_or_instantiate_nested_check_results(f, #check_round, check, new_check_result) %>
<% end %>
<% end %>
<% end %>
<% end %>
And that shoud be it ;). Let me know if it did the trick :D!
KR,
I believe it works like you want with this (code with some simplifications):
Check
class Check < ApplicationRecord
belongs_to :subchapter
has_many :check_results
def check_results_for_form check_round_id
results = check_results.where(check_round_id: check_round_id)
results.any? ? results : check_results.build
end
end
CheckRoundsController
def edit
#check_round = CheckRound.find(params[:id])
#chapters = Chapter.includes(subchapters: :checks).all
end
edit.html.erb
<%= form_for(#check_round, :url => {:action => 'update'}) do |f| %>
<ul>
<% #chapters.each do |chapter| %>
<li>
<%= chapter.name %>
chapter
<ul>
<% chapter.subchapters.each do |subchapter| %>
<li>
<%= subchapter.name %>
subchapter
<ul>
<% subchapter.checks.each do |check| %>
<li>
<%= check.name %>
check
<br>
<%= f.fields_for :check_results, check.check_results_for_form(#check_round.id) do |result| %>
<%= result.hidden_field(:check_id, :value => check.id) %>
<%= result.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s) %>
<% end %>
</li>
<% end %>
</ul>
</li>
<% end %>
</ul>
</li>
<% end %>
<ul>
<%= f.submit %>
<% end %>
Your problem is that you are repeating the display of the form fields for check_results. Look at line 7 of your view code:
<%= f.fields_for :check_results do |result| %>
This is displaying the fields for each check result on f.object (which is #check_round). However, this code gets repeated for each check in subchapter. That surrounding block gets repeated for each subchapter in chapter, and the block surrounding that gets repeated for each chapter in #chapters.
When the form is submitted, the params for check_results all have the same names, they are not distinguished by chapter, subchapter, or check. As a result, the only value that gets saved for observation is the last one submitted.
I think a solution for your case would be to only show the check_result form fields associated with the current check in the loop. One way to do that is to put a conditional in the loop starting on line 7 of your view code:
<%= f.fields_for :check_results do |result| %>
<% if result.object.check == check %>
<%= result.hidden_field(:check_id, :value => check.id) %>
<%= result.text_area(:observation, rows: 4, :id =>'obs' + check.id.to_s) %>
<% end %>
<% end %>
<% end %>
You could also just loop through the check_results independently of the loops for checks, subchapters, and chapters, but I'm assuming that you want to keep that order and context for the UI.

ActionView::Template::Error (undefined method `city' for nil:NilClass):

I'm having belongs_to / has_many relationship between Trainer and Sportists. I'm trying to loop through their values in view like this:
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.city %>
<% end %>
and the Sportist related information works fine, but the trainers - doesn't. I get the error given in the title. If I try to do this in rails console everything works, so relationships should be set fine.
Things I've tried:
<% s.trainers.each do |t| %>
<%= t.city %>
<% end %>
that gives me undefined method 'trainers' error, and if I try s.trainer I get
#<TRAINER:0X00000004CE7CB0>
So what could be the fix?
EDIT
My models:
Trainer
has_many :sportists
belongs_to :team
accepts_nested_attributes_for :sportists, :reject_if => :all_blank, :allow_destroy => true
Sportist
belongs_to :trainer
Controller
#sportists = Sportist.all
You are getting undefined method 'city' for nil:NilClass in below code:
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.city %>
<% end %>
which means that there is a sportists record which doesn't have trainer associated to it.
So, for that particular sportlist record s.trainer is nil and you cannot call city on nil object.
To identify the sportist record for which you don't have an associated trainer, just update the view code as below:
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.try(:city) %>
<% end %>
This way even if you don't have an associated trainer record, error would not be raised.
In the rendered view, just look for sportlist record which doesn't show any city, that would be the sportlist record without an associated trainer.
As for the second error undefined method 'trainers' that you received on
<% s.trainers.each do |t| %>
<%= t.city %>
<% end %>
sportlist belongs_to trainer, you only have dynamic method trainer (NOTE singular) available and NOT trainers (NOTE plural). Also, s.trainer would return a single trainer record so you cannot iterate over it with each method as it is not a collection BUT a single record.
UPDATE
Ideally, you should not have allowed creation of sportist records without a trainer.
You should have added an index on the foreign key trainer_id created on sportlists table. With this you don't even have to use try method and your current code would work as it is.
You can make use of delegate and avoid use of try, if and terniary operator.
Sportist
belongs_to :trainer
delegate :city, to: :trainer, :allow_nil => true
You need to make small change to your existing code and it will work smoothly :)
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.city %>
<% end %>
Seems like you have a sportists that doesn't have a trainer. To avoid this make an if condition like this.
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.city if s.trianer.present?%>
<% end %>
And also setting the validation in the Sportist model should resolve the empty trainer_id values
Class Sportist < ActiveRecord::Base
belongs_to :trainer
validates :trainer_id, presence: true
end
You can update your code
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.city %>
<% end %>
with
<% #sportists.each do |s| %>
<%= s.name %> <%= s.surname %>
<%= s.trainer.present? ? s.trainer.city : "No City Found" %>
<% end %>
This will stop the code to throw nil errors

check box not showing check Rails

I have a parent model that accepts child attributes.
class User < ActiveRecord::Base
accepts_nested_attributes_for :spec
attr_accessible :name, :spec_attributes
In the view I have a form that gets information for 3 models. I use a generic form_tag.
<% form_tag(action) do %>
.
.
.
<% fields_for "user[spec_attributes]" do |spec_form|%>
<%= spec_form.check_box :alert_greeting %>
<%= spec_form.label :alert_greeting, "Email me when new greetings are posted" %>
<% end %>
<% end %>
In the Controller
#user = User.find(session[:user_id])
if #user.update_attributes(params[:user])
do something.
end
The database is getting updated and the all seems to be working.
However when I go back to the form to edit again, even though the value for the checkbox is showing 1 the check box is not checked.
Any ideas as to how to show the checkbox as being checked when it is supposed to be?
Thanks a lot in advance.
You need to reference the specific spec record that is within the user you're calling. Try changing
<% fields_for "user[spec_attributes]" do |spec_form|%>
to
<% fields_for #user.spec do |spec_form|%>
You'll need to make sure that you have a non-nil spec object built for the user (but not necessarily saved) in your edit controller action.
You can do attributes and nested attributes using two fields_for calls like this:
<%= form_tag(action) do %>
... other form tags ...
<%= fields_for :user, #user do |f| %>
<%= f.text_field :first_name %>
<%= f.text_field :last_name %>
<%= f.fields_for :spec do |s| %>
<%= s.check_box :alert_greeting %>
<%= s.label :alert_greeting, "Email me when new greetings are posted" %>
<% end %>
<% end %>
<% end %>

Edit existing object and add new dependent object in rails 3 (Nested Forms)

Usually I just use something similar to
http://railscasts.com/episodes/196-nested-model-form-part-1
Now i have an existing User which i am trying to add new cars and annimals. The User has_many cars and annimals and accepts_nested_attributes_for cars and annimals
If i do
= form_for(#user) do |f|
= f.fields_for #user.cars.build do |c|
I get error:
unknown attribute: car
And if i do
= form_for(#user) do |f|
= f.fields_for :cars do |c|
I get a list of all existing cars for that user (when I want to make a new one)
Thannks!
ps: i guess i should add, i'm using simple_form_for and simple_fields_for, it might be a bug with that...
Deep inside the rails api I found:
It’s also possible to specify the instance to be used:
<%= form_for #person do |person_form| %>
...
<% #person.projects.each do |project| %>
<% if project.active? %>
<%= person_form.fields_for :projects, project do |project_fields| %>
Name: <%= project_fields.text_field :name %>
<% end %>
<% end %>
<% end %>
<% end %>
So in my case, i guess the syntax would be
= form_for(#user) do |f|
= f.fields_for :cars, #user.cars.build do |c|

rails - displaying nested find hash

I am trying to display the output of this find -
#test = User.joins(:plans => [:categories => [:project => :presentations]]).where(current_user.id)
Here is my output loop
<% #test.each do |p| %>
<%= p.plans %>
<% p.plans.each do |d| %>
<%= debug(d) %>
<% d.categories.each do |e| %>
<% e.project.each do |r| %>
<%= debug(r) %>
<% end %>
<% end %>
<% end %>
<% end %>
The loop works until it gets to project when it throws this error
undefined method `each' for "#<Project:0x000001033d91c8>":Project
If I change it to projects in the loop it gives this error
undefined method `projects' for #<Plan:0x000001033da320>
The debug at categories level shows this
--- !ruby/object:Category
attributes:
id: 2
name: test
short_name: tst
created_at:
updated_at:
category_id: 2
plan_id: 5
My relationships look like this
User
has_many :user_plans
Plan
has_many :user_plans
has_and_belongs_to_many :categories
Category
has_one :project
has_and_belongs_to_many :plans
Project
has_many :presentations, :dependent => :delete_all
Presentation
belongs_to :project
Do I need to changed my find ?
Thanks, Alex
Category has_one :project
so it is single object not collection thus no each method.
According to your relationship definitions, Category only has_one project, so why do you want to iterate over e.project? If you just want to show debugging output, replace
<% e.project.each do |r| %>
<%= debug(r) %>
<% end %>
with
<%= debug(e.project) %>
But if you want to go deeper, into presentations, do:
<%= debug(e.project) %>
<% e.project.presentations.each do |presentation| %>
<%= debug(presentation) %>
<% end %>
Your problem is that you are calling the array method .each on a single object.
category.project will give you a single Project object right? That's not an array, so you can't call each on it.
Replace this:
<% e.project.each do |r| %>
<%= debug(r) %>
<% end %>
with
debug(e.project)
While you're at it, here's some other advice: use descriptive variable names. Why does 'p' represent a test, 'd' represent a plan, 'e' represent a category, etc? Variable names should tell you what the object is. Similarly, i'd expect the variable #test to hold a Test object. In your code it seems to be an array. Use plural variable names for a variable that holds a collection of that type of object - eg #plans would be an array of Plan objects.
eg
<% #tests.each do |test| %>
<% test.plans.each do |plan| %>
<%= debug(plan) %>
<% plan.categories.each do |category| %>
<%= debug(category.project) %>
<% end %>
<% end %>
<% end %>
Isn't that more readable?

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