• a1aks
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  • Posts: 86

Re: Multiple rows of data with a single form

Hi,

After trying ankit644's code. I found this error message displaying regularly and I feel I have no values some where which makes it nil.

the errors shown are :

You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.each

Can any body tell me what mistake I am creating...

my view looks some think like this

<h2>New sample</h2>
<% form_tag :action => 'create' do %>
<% @samples.each_with_index do |sample, index| %>
<% fields_for "samples[#{index}]", sample do |f| %>
<table>
    <tr>
         <%= f.hidden_field :batch_id %>
        <th><%= f.label :sample_name %><br />
        <%= f.text_field :sname %></th>
        
        <th><%= f.label :species %><br />
        <%= f.text_field :organism, :rows => 2 %></th>
        
        <th><%= f.label :sample_type %><br />
        <%= f.select(:samp_type, %w{ DNA RNA}) %></th>
      
         <th><%= f.label :initial_concentration %><br />
        <%= f.text_field :ini_conc %></th>
      
         <th><%= f.label :initial_volume %><br />
        <%= f.text_field :ini_vol %></th>
       
        <th>
        <%= f.label :storage_space %><br />
        <%= f.text_field :storage_space %></th>
   
        <th>
        <%= f.label :sample_comment %><br />
        <%= f.text_area :samp_comment, :rows => 1 %></th>
      </tr>   
</table>
    <% end %>
    <% end %>
  <p><%= f.submit 'Submit' %></p>
<% end %>

Last edited by a1aks (2011-06-21 10:15:26)

  • jamesw
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  • From: Leeds, UK
  • Registered: 2008-06-07
  • Posts: 2,701

Re: Multiple rows of data with a single form

The new action for the samples controller needs to set up the @samples variable
To cater for the scenario where there may be no samples wrap that .each up in a condition that checks for empty something like this

<% @samples.each_with_index do |sample, index| unless @samples.empty?%>
What you want and what you need are too often not the same thing!
When your head is hurting from trying to solve a problem, stop standing on it. When you are the right way up you will see the problem differently and you just might find the solution.
(Quote by me 15th July 2009)
  • a1aks
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  • Registered: 2011-05-29
  • Posts: 86

Re: Multiple rows of data with a single form

jamesw wrote:

The new action for the samples controller needs to set up the @samples variable
To cater for the scenario where there may be no samples wrap that .each up in a condition that checks for empty something like this

<% @samples.each_with_index do |sample, index| unless @samples.empty?%>
  • a1aks
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  • Posts: 86

Re: Multiple rows of data with a single form

hey jamesw,

I tried the way you suggested me to get to the answer but I have been still unsuccessful.
My main reason is I have made two scaffolds for batches and models separately and i have made a partial for the sample.new.html in the batches folder. also I would like to know which controller should I edit, meaning as I have two controllers now, batch-controller as well as sample-controller, the methods of new and create should come in which bit...

Thank you but I am unfortunate in solving this problem

  • a1aks
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  • Registered: 2011-05-29
  • Posts: 86

Re: Multiple rows of data with a single form

chuck everything people... I think I have the solution ...

Follow this link and you will see it

Thanks to Stephen...
http://www.stephenchu.com/2008/03/param … index.html

  • a1aks
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  • Posts: 86

Re: Multiple rows of data with a single form

Hi...

Back again..

I am facing a problem again..

After I submit details in the form, i get an error message 
undefined method `stringify_keys!

Parameters:

{"commit"=>"Submit",
"authenticity_token"=>"b7fc41meCHEXhi7CEpEp/dlZou4PL2D+7J/54YEmlLA=",
"batch"=>{"submit_date(2i)"=>"6",
"bname"=>"",
"submit_date(3i)"=>"22",
"sample_no"=>"",
"submit_date(4i)"=>"14",
"grp_leader"=>"",
"submit_date(5i)"=>"08",
"contact_per"=>"",
"batch_comment"=>"",
"submit_date(1i)"=>"2011"},
"samples"=>{"1"=>{"organism"=>"",
"ini_vol"=>"",
"ini_conc"=>"",
"sname"=>""},
"2"=>{"organism"=>"",
"ini_vol"=>"",
"ini_conc"=>"",
"sname"=>""},
"samp_type"=>"gDNA",
"3"=>{"organism"=>"",
"ini_vol"=>"",
"ini_conc"=>"",
"sname"=>""}}}



looking at the last bit where sname is given, it shows that I have a hash value that takes all the parameters as strings
but not the one when i have selection tags, or text areas. could any one help me with this..

my codes are

Batches-controller
  def create
    @batch = Batch.new(params[:batch])   
   @samples = @batch.samples.build params[:samples].values
    if @batch.save
      flash[:success] = 'Good.'
      redirect_to :action => 'index'
    else
      flash[:error] ='Bad.'
       render :action => 'new'
    end
  end


## view-batches

<h1>New batch Details</h1>

<% form_for(@batch) do |f| %>
  <%= f.error_messages %>

  <p>
    <%= f.label :Batch_name %><br />
    <%= f.text_field :bname %>
  </p>
  <p>
    <%= f.label :submit_date %><br />
    <%= f.datetime_select :submit_date %>
  </p>

    <p>
        <%= f.label :number_of_samples %><br />
        <%= f.text_field :sample_no %>
      </p>
   
  <p>
    <%= f.label :group_leader %><br />
    <%= f.text_field :grp_leader %>
  </p>
  <p>
    <%= f.label :contact_per %><br />
    <%= f.text_field :contact_per %>
  </p>
  <p>
    <%= f.label :batch_comment %><br />
    <%= f.text_area :batch_comment, :rows => 3 %>
  </p>

    <%= render :partial => 'sample_details' %>


<p><%= f.submit 'Submit' %></p>
<% end %>

<%= link_to 'Back to Batches', batches_path %>


# view of the partial I created as sample_details

<table>
  <tr>
    <th>Sample Name  </th>
    <th>Species  </th>
    <th>Sample type  </th>
    <th>Concentration</th>
    <th>Volume</th>
    <th>Sample comment</th>
  </tr>

<% (1..3).each do |index| %>
<% fields_for :samples do |ff| %>
<tr>   
    <td><%= ff.text_field :sname, :index => index, :size => 15 %></td>
    <td><%= ff.text_field :organism, :index => index, :size => 15 %></td>
    <td><%= ff.text_field :ini_conc, :index => index, :size => 3 %></td>
    <td><%= ff.text_field :ini_vol, :index => index, :size => 3 %></td>
    <td><%= ff.select(:samp_type, %w{ gDNA totalRNA cDNA}) %></td>
</tr>
<% end %>
<% end %>
</table>


model is the same as before..

Thanks in advance for helping

  • Registered: 2009-12-02
  • Posts: 95

Re: Multiple rows of data with a single form

How would I do this in Rails 3.0.3 with a single model?


ryanb wrote:

You're right, there are some significant differences. Try this code.

def new
  @owners = Array.new(3) { Owner.new } # set up any defaults here
end
def create
  @owners = params[:owners].values.collect { |owner| Owner.new(owner) }
  if @owners.all?(&:valid?)
    @owners.each(&:save!)
    redirect_to :action => 'index'
  else
    render :action => 'new'
  end
end
# in new.rhtml
<%= start_form_tag :action => 'create' %>
<% @owners.each_with_index do |owner, index| %>
  <% fields_for "owners[#{index}]", owner do |f| %>
    First Name: <%= f.text_field :firstname  %>
    Last Name: <%= f.text_field :lastname  %>
  <% end %>
<% end %>
<%= end_form_tag %>

If you have any questions about the code feel free to ask.

  • Registered: 2013-05-02
  • Posts: 3

Re: Multiple rows of data with a single form

You're right, there are some significant differences. Try this code.

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