I'm trying to display group name (product_group) followed by the items (product) in each group.
<% #products.group_by(&:product_group_id).each do |s|%>
<!--need to get group name here ->
<% s[1].each do |d|%>
<%= d.product_name%>
<br>
<%end%>
<%end%>
rails 2.3.8
First, I strongly recommend using two variables in your block. When you use one variable, group_by sets the variable to an array of the pair of values which should be set as two variables. It will be much more clear code than indexing the pair with [1] for the group.
One way is that the first part of the pair will be the id, so you can do a find.
<% #products.group_by(&:product_group_id).each do |product_group_id, products|%>
<!--need to get group name here -->
<%= ProductGroup.find(product_group_id).name %>
<% products.each do |product|%>
<%= product.product_name%>
<br>
<% end %>
<% end %>
Another way, is since you have an array of at least on product in the group, you can call the product_group association on the first element of the array.
<% #products.group_by(&:product_group_id).each do |product_group_id, products|%>
<!--need to get group name here -->
<%= products[0].product_group.name %>
<% products.each do |product|%>
<%= product.product_name%>
<br>
<% end %>
<% end %>
You can also delegate the name to the product group.
class Product
belongs_to :product_group
delegate :name, :to => :product_group, :prefix => true, :allow_nil => true
end
<%= products[0].product_group_name %>
Group by needs two variables in the block declaration. The first for the thing you are grouping by, and the second to hold the things in each of the groups.
<% #products.group_by(&:product_group_id).each do |group_id, group_products| %>
Group ID: <%= group_id %>
<br>
Products:
<% group_products.each do |product| %>
<%= product.product_name %>
<% end %>
<% end %>
Related
I need to access the same random shuffling across two different loops on the same ERB page.
Context:
I have questions which have five choices of which one is TRUE for choices.is_correct.
My current ERB (below) successfully displays:
1) Grouped by usage
2) All available questions (shuffled)
3) And all five choices (also shuffled)
What I'd like to add is a separate loop (directly after in the same ERB), which gives:
1) Same grouping by usage
2) Same order of available questions (eg, same shuffle order)
3) The correct answer choice (eg, answer "B" = referencing the same shuffling)
Assigning the question or choice shuffling globally would not work, as I need it to be randomized on each page load.
Current ERB (currently shuffles each loop separately)
<%= #exam.name %>
<br />
<% alpha_numbers = ("A".."Z").to_a %>
<% #book_questions_by_usage.each do |usage, question| %>
<h4><%= usage if usage %></h4>
<% question.shuffle.each_with_index do |question, i| %>
<%= i+1 %>: <%= question.name %>
<ol type="A">
<% question.choices.shuffle.each_with_index do |choice, index| %>
<% choice.alpha_order = alpha_numbers[index] %>
<li><%= choice.name %></li>
<% end %><br />
</ol>
<% end %>
<% end %>
<% #book_questions_by_usage.sort.each do |usage, question| %>
<h4><%= usage if usage %></h4>
<% question.shuffle.each_with_index do |question, i| %>
<%= i+1 %>: <%= question.name %>
<ol type="A">
<% question.choices.select { |choice| choice.correct }.shuffle.each_with_index do |choice, index| %>
<% choice.alpha_order = alpha_numbers[index] %>
Correct Answer: <b><%= choice.alpha_order %>. <%= choice.name %></b>
<% end %><br />
</ol>
<% end %>
<% end %>
question.rb
class Question < ApplicationRecord
before_validation :assign_questionable
belongs_to :questionable, polymorphic: true
has_many :choices, :dependent => :destroy
accepts_nested_attributes_for :choices, allow_destroy: true
choice.rb
class Choice < ApplicationRecord
belongs_to :question
I've spent hours looking into possible solutions with no success so far. Any help is much appreciated!
How about you don't shuffle in the view, but in the controller. Save the shuffled array in an instance method and then use it in the view where you need it.
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.
I'm looking to get the last 5 items in an array, but to display each item individually, not as a group.
Here's what I've tried below with no success.
#array = Town.all
<% #array.each_slice(5) do |a| %>
<%= a.first %>
<%= a.second %>
<%= a.third %>
<%= a.fourth %>
<%= a.fifth %>
<% end %>
I can't figure out how to pull out a specific number of items and then to call each individual item.
The method you are looking for is in_groups_of (https://apidock.com/rails/Array/in_groups_of):
<% #towns.in_groups_of(5) do |five_towns| %>
<% five_towns.each do |town| %>
# [...]
<% end %>
<% end %>
Update: Maybe you want only the last 5 elements of the array. If so, you can simply call:
Town.all.last(5)
# => array of (max) 5 Town records
To get the last 5 items of an Array you could use last and then iterate them with each:
<%= #array.last(5).each do |a| %>
...
<% end %>
But it seems that you want to get the last 5 records of a model; in that case, you could try this instead:
#array = Town.limit(5).order('id desc')
<%= #array.each do |a| %>
...
<% end %>
... is there a way that I can have let's say the last 5 records of a
model all within one loop? maybe
<%= #array.each do | a, b, c, d, e| %>
<%= a.description %>
<%= b.description %>
<% end %>
You could use the index of each item instead of using each; for example:
#last_five = #array.last(5)
<%= last_five[0] %>
<%= last_five[1] %>
<%= last_five[2] %>
<%= last_five[3] %>
<%= last_five[4] %>
Although that wouldn't be DRY, so it will be better to stick with each.
I'm new to rails and I'm trying to build a view that will list the parents and related children
Ex:
Passport has many Visas
I want to list information about the passport and the visas that the passport has.
So I have
<% #passport_list.each do |passport| %>
# passportFields
<% passport.visas.each do |visa| %>
<%= t.text_field :visa_type %>
<% end %>
<% end %>
I'm getting the error
undefined method `visa_type' for #Passport:0x000000091b8b28
It looks like rails is trying to find the property visa_type for passport, instead of in visa. How does the scope work within each? Can I force it to access visa_type from visa?
I think you're looking for the fields_for form helper. This will allow you to create fields for the relevant visa attributes. Replace your code sample with the following, and you should be all set.
<% #passport_list.each do |passport| %>
# passportFields
<% t.fields_for :visas do |visa_fields| %>
<%= visa_fields.text_field :visa_type %>
<% end %>
<% end %>
You can also iterate over the list as follows:
<% #passport_list.each do |passport| %>
# passportFields
<% passport.visas.each do |visa| %>
<% t.fields_for :visas do |visa_fields| %>
<%= visa_fields.text_field :visa_type %>
<% end %>
<% end %>
<% end %>
For more information on fields_for, check out the link I added above, and to customize further for your use case, check out the "One-to-many" section.
IMO you should always handle the null case of an object.
Something like this if you use rails (present? is a Rails function)...
<% if #passport_list.present? %>
<% #passport_list.each do |passport| %>
passportFields
<% passport.visas.each do |visa| %>
<%= t.text_field :visa_type %>
<%end%>
<%end%>
<% else %>
<p>Nothing to see here</p>
<% end %>
However if your #passport_list is backed by an ActiveRecord Query, you can handle this in the model/helper/controller by returning the .none query on the model. Note that this differs from an empty array because it is an ActiveRecord Scope, so you can chain AR queries onto it
# scope on AR model
def self.awesomeville
where(country_of_origin: "awesomeville")
end
# method queried in controller
#passport_list = Passport.all
if #passport_list.present?
#passport_list
else
Passport.none
end
# additional filtering in view is now possible without fear of NoMethodError
#passport_list.awesomeville
Whereas a ruby Array would raise an error as it would respond to the Array methods.
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?