Problem when editing record in polymorphic relation

Rails
1

I have the following three models created applying the polymorphic
concept

class SoftwareCi < ActiveRecord::Base
has_one :ci, :as => :content
end

class HardwareCi < ActiveRecord::Base
has_one :ci, :as => :content
end

class Ci < ActiveRecord::Base
belongs_to :content, :polymorphic => true
end

The table, cis ,contains the following records

id | ci_number | content_id | content_type
----±---------±----------±-----------±-------------
1 | CI1 | 1 | SoftwareCi
2 | CI2 | 2 | SoftwareCi
3 | CI3 | 1 | HardwareCi
4 | CI4 | 2 | HardwareCi

The table, software_cis ,contains the following records

id | asset_tag | status | version
----±------------------±--------±--------
1 | AC Logix - AT1 | Status2 | 1.0
2 | RR Logix AT2 | Status3 | 2.3

The table, hardware_cis ,contains the following records

id | asset_tag | status | version
----±------------------±--------±--------
1 | HCL - AT1 | Status1 | 1.0
2 | IBM - AT2 | Status1 | 2.3

The controller, ci_controller, contains the edit method as follows

def edit
@ci=Ci.find(1)
end

My Problem

In the edit.rhtml file, I am trying to populate the value of ‘version’,
an attribute in the software_ci table which is represented by the
content_type, SotwareCi. The sample code is given below.

<%= text_field ci.content, “version”, “size” => 20 %>

I am assuming ‘ci.content’ in the above code will represent the model
and ‘version’ will represent the attribute of that model.

When executed the above code didn’t work.
What is wrong here? How I have to proceed?
If we want to simply display the value of ci.content.version, it works
but when tried to edit, it doesn’t work

Thanks in advance for your help

2

On 2 Jan 2008, at 14:22, Venu Vallayil wrote:

My Problem

In the edit.rhtml file, I am trying to populate the value of
‘version’,
an attribute in the software_ci table which is represented by the
content_type, SotwareCi. The sample code is given below.

<%= text_field ci.content, “version”, “size” => 20 %>

text_field doesn’t work that way - it expects the first parameter to
be the name of an instance variable
You should look into form_for since it allows you to escape that
convention

Fred

3

Frederick C. wrote:

On 2 Jan 2008, at 14:22, Venu Vallayil wrote:

My Problem

In the edit.rhtml file, I am trying to populate the value of
‘version’,
an attribute in the software_ci table which is represented by the
content_type, SotwareCi. The sample code is given below.

<%= text_field ci.content, “version”, “size” => 20 %>

text_field doesn’t work that way - it expects the first parameter to
be the name of an instance variable
You should look into form_for since it allows you to escape that
convention

Fred

I created as follows but didn’t work

<% form_for :ci, @ci, :url => { :action => “update” } do |f| %>
CI Name: <%= f.content.text_field :name %>
<% end %>

Thanks
Venu

4

On 2 Jan 2008, at 14:57, Venu Vallayil wrote:

<% form_for :ci, @ci, :url => { :action => “update” } do |f| %>
CI Name: <%= f.content.text_field :name %>
<% end %>

That doesn’t mean anything - you need
form_for :co, @ci.content, … do |f|
f.text_field :name
end

If the form as a whole should apply to ci rather than its content then
you can use fields_for to create the fields (without creating the

tag)

Fred

5

On 2 Jan 2008, at 15:34, Venu Vallayil wrote:

That doesn’t mean anything - you need

Fred…will you be able to show me a sample code that tells how a
record is to be edited when there exists a polymorphic relation as
shown
in the starting thread of this talk

The polymorphism is (I think) irrelevant, it’s the fact that there is
an association. There is a good series on railscasts.com about complex
forms.

Fred

6

Frederick C. wrote:

On 2 Jan 2008, at 15:34, Venu Vallayil wrote:

That doesn’t mean anything - you need

Fred…will you be able to show me a sample code that tells how a
record is to be edited when there exists a polymorphic relation as
shown
in the starting thread of this talk

The polymorphism is (I think) irrelevant, it’s the fact that there is
an association. There is a good series on railscasts.com about complex
forms.

Fred

But nobody talks/shows the code about editing a record keeping the
concept I introduced in my starting thread…seems to be i am lost
somewhere…can’t proceed…thanks for your support. Really
appreciate your support.

7

Frederick C. wrote:

On 2 Jan 2008, at 14:57, Venu Vallayil wrote:

<% form_for :ci, @ci, :url => { :action => “update” } do |f| %>
CI Name: <%= f.content.text_field :name %>
<% end %>

That doesn’t mean anything - you need
form_for :co, @ci.content, … do |f|
f.text_field :name
end

If the form as a whole should apply to ci rather than its content then
you can use fields_for to create the fields (without creating the

tag)

Fred

Fred…will you be able to show me a sample code that tells how a
record is to be edited when there exists a polymorphic relation as shown
in the starting thread of this talk

Thanks
Venu