After the user submits the form, but before the association is added, is it possible to modify the nested field during this time?
For example my nested fields may look like:
<div class='nested-fields'>
<div class="field">
<%= f.label :count %>
<%= f.number_field :count %>
</div>
<%= link_to_remove_association "remove section", f %>
</div>
Say I want to multiply count x 2 before adding the association (after user submits form). Is this possible?
Or a more complex example, I might want to convert the integer to a string then save the association.
link to issue: https://github.com/nathanvda/cocoon/issues/361 (i was told to post on SO)
Yes, you can modify you permit params:
def some_params
params.require(:some).permit(:count).tap do |white_list|
white_list[:count] = 2 * params[:some][:count].to_i
end
end
Related
I'm making an app where some activities are listed in a table called Fakultety (polish language, sorry), and participants on in another table called Uczestnicy.
I have a submit form where you can submit yourself to an activity, but I'm stuck on passing values to a DB. Firstly, I don't know how to tell to the database on which activity you want to be assigned to (I tried to change the submit button id to an activity id and then passing it into a database but don't know how to do this id: "#{#fakultet.id}" not working) and later I want to count how many people are assigned to field participants in a database Fakultety, but I don't want to pass all the data, just ID of the users from table called Uczestnicy. How to do it? I mean just to pass the ids to another table, and how to tell the database on which activity I want to be assigned to?
This is my form view:
<h1>Zapisujesz sie na fakultet</h1>
<div class="form-group">
<div class="row">
<div class="col-md-6 col-md-offset-3">
<%= form_for(#participant, url: zapisy_path) do |f| %>
<p>Imię:</p>
<%= f.text_field :firstName, class: 'form-control' %>
<p>Nazwisko:</p>
<%= f.text_field :lastName, class: 'form-control' %>
<p>Grupa:</p>
<%= f.text_field :group, class: 'form-control' %>
<%= f.submit "Zapisz się", class: "btn btn-primary" id: "#{#fakultet.id}"%>
<% end %>
</div>
</div>
</div>
Does anybody understand me and can help me?
Rails provides form collection helpers that make it really easy to assign associations:
# I'm going to just do this in english
<%= form_for(#activity) do |f| %>
<%= f.collection_select(:participant_ids, Partipicant.all, :id, :name, prompt: true, multiple: :new) %>
# ...
<% end %>
Then whitelist the attribute as an array:
params.require(:activity).permit(:foo, :bar, participants_ids: [])
Thats all you actually need to assign childen to to a parent resource. This is done as a part of the normal create/update actions of the parent resource.
You don't actually need the form for the child records unless you actually want to be creating the record. In that case you can setup a nested resource or if you want to create/edit multiple nested records at the same time as the parent record you can use nested attributes.
First you should rename your models and tables, to English, it's a really bad pattern to use your language, in English it is easier to understand by other devs.
According to the problem, probably what you are looking for is hidden_field
<%= f.hidden_field :fakultet_id, :value => #fakultet.id %>
and if you want to query Fakultety that have user assigned, you can select Fakultety where participant_id is not nil
Fakultety.where.not(participant_id: nil)
I'm trying to offer teachers a form that will create multiple students at once. It seems that most people tackle this concept with nested attributes, but I'm having a hard time understanding how that would work when I'm only using a single model. This article made it seem possible to achieve this without nested attributes, but my results are not working the way the author suggests. The students array should include one hash for each section of the form. But when I submit the form and check the parameters, only one single hash exists in the array.
Adjusting her approach, I've got this controller:
students_controller.rb
def multi
#student_group = []
5.times do
#student_group << Student.new
end
end
(I'm using an action I've called "multi" because it's a different view than the regular "create" action, which only creates one student at a time. I've tried moving everything into the regular create action, but I get the same results.)
The view:
multi.html.erb
<%= form_tag students_path do %>
<% #student_group.each do |student| %>
<%= fields_for 'students[]', student do |s| %>
<div class="field">
<%= s.label :first_name %><br>
<%= s.text_field :first_name %>
</div>
<div class="field">
<%= s.label :last_name %><br>
<%= s.text_field :last_name %>
</div>
<% end %>
<% end %>
<div class="actions">
<%= submit_tag %>
</div>
<% end %>
The results:
(byebug) params
<ActionController::Parameters {"utf8"=>"✓", "authenticity_token"=>"3Xpi4XeqXuPs9jQvevy+nvGB1HiProddZzWq6Ed7Oljr3TR2fhx9Js6fN/F9xYcpgfDckCBOC2CoN+MrlFU0Bg==", "students"=>{"first_name"=>"fff", "last_name"=>"ggg"}, "commit"=>"Save changes", "controller"=>"students", "action"=>"create"} permitted: false>
Only one has is included for a student named "fff ggg". There should be four other hashes with different students.
Thank you in advance for any insight.
fields_for is only used in conjunction with form_for. The for is referring to a model, which it expects you to use. Since you're trying to build a form with no model, you have to construct your own input field names.
Don't use fields_for but instead, render each input using the form tag helpers e.g.
<%= label_tag "students__first_name", "First Name" %>
<%= text_field_tag "students[][first_name]" %>
...and so on.
The key is that the field names have that [] in them to indicate that the students parameters will be an array of hashes. You almost got it by telling fields_for to be called students[] but fields_for ignored it because it needs a model to work correctly.
I am using the cocoon gem to try and achieve adding an object which belongs to another with nested fields. I have a 'user_resolution' which has many 'milestones'. I have set up the associations accordingly in both of these models. For some reason, milestones are failing to be created, however if I add one manually in the database I can successfully update it. I am able to dynamically add the fields and remove them using the cocoon gem but that is all. When I click 'add milestone' it redirects me to the show view of the user resolution and throws the success message saying user resolution has been updated, no errors are thrown but the milestone(s) is/are not created.
user_resolution.rb
has_many :milestones
accepts_nested_attributes_for :milestones, reject_if: :all_blank, allow_destroy: true
milestone.rb
belongs_to :user_resolution
I have set up the nested form within the edit view as for now I only want users to add a milestone to a resolution in the edit view.
user_resolutions/edit.html.erb
<%= form_for(#user_resolution) do |f| %>
<div class="field">
<%= f.label :name %><br>
<%= f.text_field :name %>
</div>
<div class="field">
<%= f.label :description %><br>
<%= f.text_area :description %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<%= f.fields_for :milestones do |milestone| %>
<%= render 'milestone_fields', f: milestone %>
<% end %>
<%= link_to_add_association 'Add Milestone', f, :milestones %>
<%= f.submit "Add Milestone" %>
<% end %>
_milestone_fields.html.erb
<div class="nested-fields">
<div class="field-row">
<%= f.label :name, 'Name' %>
<%= f.text_field :name %>
</div>
<div class="field-row">
<%= f.label :description, 'Name' %>
<%= f.text_area :description %>
</div>
<div class="field-row">
<%= f.label :severity, 'severity' %>
<%= f.check_box :severity %>
</div>
<div class="field-row">
<%= f.label :target_date, 'target_date' %>
<%= f.date_select :target_date %>
</div>
<%= link_to_remove_association 'Remove', f %>
</div>
The permitted parameters within the user resolutions controller also contain the following
milestones_attributes: [:id, :user_resolution_id, :name, :description, :target_date, :severity, :complete, :_destroy]
The milestones themselves have no views, they only have a model and a controller. The controller create action (which i'm unsure is required for nested forms) contains the standard following code
def create
#milestone = Milestone.new(milestone_params)
if #milestone.save
redirect_to user_resolutions_path,
:flash => { :success => "You successfully created a milestone" }
else
redirect_to new_milestone_path,
:flash => { :error => "Oops something went wrong. Try again." }
end
end
I've been as informative as I can but if you need anything else let me know. Thanks guys.
which i'm unsure is required for nested forms
You don't need a create action for milestones - they'll be populated from the user_resolutions#create controller action.
There are several things to look at with this. I'll detail some here. This won't be a specific answer, but may help point you in the right direction.
Firstly, you need to make sure you're receiving the correct params.
Cocoon does a great job building the nested form - you need to make sure it's obliging Rails' nested attribute structure.
To do this, you should right-click > view source.
In the f.fields_for section (it won't be called that in the HTML), you'll be looking for the equivalent to the following:
<input type="text" name="milestones_attributes[0][name]" value="">
The important thing to note is the name...
Each time you use a form, or any Rails view helper for that matter, you're really just building standard HTML. form_for just creates an HTML form, and thus any params contained within it need to adhere to a certain structure for Rails to recognize the params.
The f.fields_for elements will typically be called x_attributes[:id][:param] - this is passed to Rails, which cycles through each [:id] to determine the number of nested params to add.
You need to check the source for the above naming structure. If you see it, that's good. If not, it means you haven't built your form properly.
Secondly, you need to make sure your objects are being built in the controller.
I'm not sure how Cocoon does this, but essentially, each time you use f.fields_for, you have to build the associated object before:
def new
#user_reservation = UserReservation.new
#user_reservation.milestones.build #-> this is what makes f.fields_for work
end
If the first step shows incorrect element naming, it means your associative objects are not being built (which is why they're not being recognized).
To test it, you should build the associative objects in the new method, before sending.
Finally, you'll want to post your params.
These tell you in explicit detail what Rails is doing with the nested attributes, allowing you to determine what's happening with them.
Sorry for the long-winded answer. You'll not have received any answers anyway, so I felt it prudent to give you something.
i'm new to MongoDB and unsure how to use the Array-Field-Type.
So i created in my model
field :admins, type: Array
in this field i wanna store all user_ids that are "admins" of the model. But when I try to set this field, it doesnt save the Information in the Array it just simple creates an String with the ID. And due to my constrain that only Admins can edit my filter function
def check_if_admin
unless Agency.find(params[:id]).admins.include?(current_agent.id)
flash[:notice] = "Only possible as Admin."
redirect_to root_path
end
end
gets the error that
"can't convert Moped::BSON::ObjectId into String"
So I tried to initiate my field with in the create def as an array with ID:
#agency.admins = [current_agent.id]
That does the Trick for one user in the Array but how do I add IDs to this field?
When I go into my Edit Form:
<%= form_for(#agency) do |f| %>
<div class="field">
<%= f.label :name %><br />
<%= f.text_field :name %>
</div>
<div class="field">
<%= f.label :admins %><br />
<%= f.text_field :admins %> <br />
</div>
<div class="field">
<%= f.label :agents %><br />
<%= f.text_field :agents %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
And Type in another User_ID by hand, I'm back to my error again.
Anyone knows how to get around that?
Thanks a ton for ur help!
This message means that at some point you stored a string where there should be an ObjectId. Ruby is trying to compare current_agent.id (an ObjectId) with params[:id] (a string).
It seems like you are not converting the input from the text_field in the form to an ObjectID before you push it onto the array.
Take the input from the admins field and make ObjectId's like this:
BSON::ObjectId.new(string_representing_admin_id)
I'm guessing the admins field is a comma separated array of admin _ids and that you are using some _id values that are easy to work with, like a username instead of a generated ObjectId as this would be very burdensome to work with.
In that case you would probably split and strip the input and then make an array of the ObjectIds using a map/select.
It would be much easier to use a select field that displayed usernames for something like this in rails right?
Anyway, show some sample documents from the collection if you need more help.
Im working with Rails 3.0.3
I want to create bills in my App. Each Bill has many entries (Material, how much of that and the Price)
The Problem i have, is that i want to write the bill and the entries and then save both at the same time. So when you click on save Bill, the Bill + each Entry should be created (saved in the db).
I can write the bill + each entry (with javascript), but i dont know how i could save both of them. Right now i can only save the bill it selft. Is it possible to pass a dynamic field via params so i can handle that in the bills controller to save? How would you implement this?
What you are looking for is called nested form, you have a main form for your bill and multiple forms that are dynamically generated as children of this general form using fields_for like this:
<% form_for #bill do |f| %>
<%= f.error_messages %>
<p>
<%= f.label :name %><br />
<%= f.text_field :name %>
</p>
<% f.fields_for :entry do |builder| %>
<%= render "entry", :f => builder %>
<% end %>
<p><%= f.submit "Submit" %></p>
<% end %>
Of course you will need some js for the dynamic creation of the different entries, here you have a couple of railscasts that will be helpfull.
Nested model form Part 1
Nested model form Part 2