Rails partial view set value of form field - ruby-on-rails

Okay so I am quite new to Rails and am trying to do the following without success:
I have an Object (from my Active Record) containing a project, which contains n sub-projects, which contain n tasks. Now for each of these I want a partial view.
So I render from the project view the sub-project with the following code:
<%= render(:partial => 'subproject', :collection => #project.sub_projects) %>
Within my sub-project partial view called _subproject.rhtml (adding the code to a good ol Rails 1.2.3 project), so I can access the data like this:
<%= subproject.name %>
That will print out the name alright but when I try to generate a textfield this won't work:
<%= text_field 'subproject', 'name' %>
But this will:
<%= text_field 'subproject', 'name', :value => subproject.name %>
What am I doing wrong?
Edit: Changed title due to my problem is not passing the value but displaying it within a form field.
Edit2: As requested my controller code:
#project = Project.find(params[:id])

You can write this:
<%= render(:partial => 'subproject', :collection => #project.sub_projects) %>
as
<%= render :partial => #project.sub_projects %>
This will render every sub project with the sub_projects/_sub_project.html.erb partial. A little shortcut.
This:
<%= text_field 'subproject', 'name' %>
Says create a text_field called: subproject[name], but doesn't give it a value. You need to pass the value you want to set (the code that works).
The more idiomatic way of doing this now is with form_for:
<% form_for #subproject do |f| %>
<%= f.text_field :name %>
<% end %>
Or if you're using formtastic (https://github.com/justinfrench/formtastic), which is fantastic, you'd write:
<% semantic_form_for #subproject do |f| %>
<%= f.input :name %>
<% end %>
I hope this helps!

Related

Rails datetime_local_field help not pre filling

I have a Job model with a first_booking_time attribute. The datetime_local_field form helper doesn't pre fill the attribute stored on the Job instance.
# renders empty field even though job.first_booking_time is set
<%= form_for #job do |f| %>
<%= f.datetime_local_field :first_booking_time %>
<% end %>
However, if I use the datetime_local_field_tag helper and pass in the value, it works:
# pre fills what's in job.first_booking_time
<%= form_for #job do |f| %>
<%= datetime_local_field_tag 'job[first_booking_time]', #job.first_booking_time %>
<% end %>
How can I use the first syntax with the helper pre filling?
Try the below code
<%= f.datetime_local_field :first_booking_time , :value => #job.first_booking_time %>

Using observe_field on an field inside a fields_for

I'm trying to observe a field that get generated inside a fields_for loop.
The thing is that the id of that field is generated dynamically.
_form.html.erb
<% form_for #exp, :url => {:action => "update"} do |f| %>
<% f.fields_for:patterns do |builder| %>
<%= render 'pattern_fields', :f => builder %>
<% end %>
<% end %>
_pattern_fields.html.erb
Pattern: <%= f.select(:LC_PATTERN, [['stripes', 'stripes'],
['dots', 'dots'],
['lines', 'lines'],
],{ :prompt => "Please select"}
) %>
<%= observe_field("------", :frequency => 1,
:with => "'id='+value", :function => 'alert(value)')%>
My question is how do i get the id of the field inside the fields_for tag.
I finally got it. Found this solution on the internet...Hope it might be of help to someone else.
In your application_helper.rb, add the following functions:
def sanitized_object_name(object_name)
object_name.gsub(/\]\[|[^-a-zA-Z0-9:.]/,"_").sub(/_$/,"")
end
def sanitized_method_name(method_name)
method_name.sub(/\?$/, "")
end
def form_tag_id(object_name, method_name)
"#{sanitized_object_name(object_name.to_s)}_#{sanitized_method_name(method_name.to_s)}"
end
You can then view the id of the fields generated inside 'fields_for' by using the following code:
<%=form_tag_id(f.object_name, :LC_PATTERN) %>

Forms blank when rendering a partial when using a collection of objects. Help!

Alright, I know my title is a little obscure but it best describes the problem I am having.
Essentially, I have a list of users, and want to be able to edit their information in-line using AJAX.
Since the users are showing up in rows, I am using a partial to render the data and the forms (which will be hidden initially by the ajax), however, when the rows are rendered currently only the last item has it's form's fields populated.
I suspect this has something to do with the fact that all the form fields have the same id's and it is confusing the DOM. But I don't know how to make sure the id's are unique.
Here is a small example:
In my view:
<%= render :partial => 'shared/user', :collection => #users %>
My partial (broke down to just the form) note that I am using the local variable "user"
<% form_for user, :html => {:multipart => true} do |f| -%>
<%= f.label :name, "Name*" %>
<%= f.text_field :title, :class => "input" %>
<%= f.label :Address, "Address" %>
<%= f.text_field :address, :class => "input" %>
<%= f.label :description, "Description*" %>
<%= f.text_area :description, :class => "input" %>
<% end -%>
When the html is rendered each form has a unique id (for the id of the user) but the elements themselves all have the same id, and only the last user form is actually getting populated with values.
Does anyone have any ideas?? :)
Thanks in advance!
Alright, after having some lunch and regaining some brain cells, (and with a little help from Google) I figured this one out.
When passing a collection to a partial like this:
<%= render :partial => 'shared/user', :collection => #users %>
Rails creates a counter variable that you can use to define an index for the form in the form of "variable_counter":
<% form_for user, :index => user_counter, :html => {:multipart => true} do |f| -%>
This adds the index number to the form id as well as all the field id's and solved my little problem. :)
I hope this helps out someone else with this issue. :)

Rails: Using form (collection select) to call show-action

A model named 'book' with attributes 'name' and 'id' is given. How can i use this collection select to call the show-action of a certain book? The one code mentioned below returns the following error message:
Couldn't find Book with ID=book_id
<% form_tag(book_path(:book_id)), :method => :get do %>
<p>
<%= label(:book, :id, 'Show Book:') %>
<%= #books = Books.find(:all, :order => :name)
collection_select(:book, :id, #books, :id, :name)
%>
</p>
<p>
<%= submit_tag 'Go' %>
</p>
<% end %>
book_path is generated once only, for the form tag itself. It won't be updated whenever your selection changes.
When you submit that form, it's going to request the following URL:
/books/book_id?book[id]=5
Since your book_path thinks book_id is the ID number you wanted, it tries to look that up. You could do what you want you by changing the code in your controller from:
#book = Book.find(params[:id])
to:
#book = Book.find(params[:book][:id])
But it kind of smells bad so be warned.
You can create a new route that is not based on the id, like
get 'books/show' # put this above your "resources :books"
and change your form to
<% form_tag books_show_path, :method => :get %>

Multiple links on a Rails view that each perform different actions - how best to handle this?

One of the things I'm doing includes several links on the show view. For instance, I have a link (or button) for "Accepting", and another one for "Rejecting". Click on Accept, and the model updates the is_accepted field as true, click on Reject, and the is_accepted field is false.
Now, how best do I handle this? In ASP.NET, I would have simply created a LinkButton and written a handler, but Rails doesn't work that way, so I'm trying to figure out how to essentially replicate what a LinkButton would do.
Right now, I'm coding two forms on the same view, nearly identical, that look like this:
<%= form_for #thing do |f| %>
<%= hidden_field_tag 'thing[is_accepted]', '1' %>
<%= f.submit "Accept" %>
<% end %>
<%= form_for #thing do |f| %>
<%= hidden_field_tag 'thing[is_accepted]', '0' %>
<%= f.submit "Reject" %>
<% end %>
This feels weird to me, but I can't seem to find anything that says this is the wrong way to do it.
I could, I assume, dry things up by using a partial and/or a helper method, but I wanted to make sure I'm on the right track and not doing something totally wrongly.
You can give your submit tag a name.. ie
<%= form_for #thing do |f| %>
<%= hidden_field_tag 'thing[is_accepted]' %>
<%= f.submit "Accept", :name => 'accept' %>
<%= f.submit "Reject", :name => 'reject' %>
<% end %>
Then you can detect the name in params[] and skip the '1'/'0' value.
I think you're going about it the right way. One way to clean up your forms is by using the model form helpers all the way through, so you'd end up with something like
<%= form_for #thing do |f| %>
<%= f.hidden_field :accepted, :value => true %>
<%= f.submit "Accept" %>
<% end %>
<%= form_for #thing do |f| %>
<%= f.hidden_field :accepted, :value => false %>
<%= f.submit "Reject" %>
<% end %>
But other than that, it looks like the right way to go about it. I would suggest against creating new methods to do this, because you're not doing anything outside of normal web requests (updating a model in this instance).
Using the submit tag as the switch and detecting it in params[] is also a good way, but I usually prefer to keep my controllers as vanilla as possible. In the end, both of these ways would end up with the same amount of 'stuff' in the UI, so whichever style you'd rather use should be fine.
Depending on how you want your UI to work you might consider link_to_remote (part of the prototype helper) - you can specify an action, params etc, and have it return some JS that gets run.
If you're using map.resources in your routes.rb you should be able to do something like this:
map.resources :things, :member => {:accept => :get, :reject => :get}
Then in your controller:
def accept
#thing = Thing.find(params[:id])
#thing.is_accepted = true
#thing.save
end
def reject
#thing = Thing.find(params[:id])
#thing.is_accepted = false
#thing.save
end
And finally in your view:
<%= link_to 'Accept', accept_thing_url(#thing) %>
<%= link_to 'Reject', reject_thing_url(#thing) %>
Or if you are using Ajax:
<%= link_to_remote 'Accept', :url => accept_thing_url(#thing) %>
<%= link_to_remote 'Reject', :url => reject_thing_url(#thing) %>

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