Helpers -- Problem using one

rubyonrails-talk
1

Hi All,

I've got a view "app\views\home\start..rhtml" that invokes a partial template with:

< %= render :partial => "customer/list" % >

(spaces inserted between % and its associated angle bracket here and in the following code).

The partial view "app\views\customer\_list.rhtml" creates a link with the code:

< %= link_to(c.name,

  :controller => 'customer',

  :action => 'show',

  :id => c.id)

% >

I'd like to replace the code in the partial view with a one-line helper:

< %= link_to_customer(c) % >

and define the helper in the module in "app\helpers\customer_helper.rb" with:

def link_to_customer(c)

   link_to(c.name,

      controller => 'customer',

      action => 'show',

      id => c.id)

end

When I tried this, I got:

undefined method `link_to_customer' for #<#<Class:0x3cb2710>:0x3cb2278>

Any ideas of a way to get this going?

Thanks in advance,

Richard

2

Hi Curtis,

Great explanation!! Especially the alternative options!!

Thanks a lot. Richard

Curtis Summers wrote:

3

Hi Curtis,

Woops. I'm not out of the woods yet.

I'm assuming you are calling this partial while in the home controller

Right.

2) Move your link_to_customer definition to application_helper.rb so it will be available to all controllers/views.

Chose this option, definition same as before.

Substituted my helper invocation in app\views\customer\_list.rhtml (line 12) and got error messages (looks like it's looking for 'show' in home rather than customer folder):

NameError in Home#start

Showing app/views/customer/_list.rhtml where line #12 raised:

undefined local variable or method `action' for #<#<Class:0x3cd7520>:0x3cd7418>

Extracted source (around line #12):

9: <% @customers.each do |c| %> 10: <tr> 11: <td> 12: <%= link_to_customer(c) %> 13: </td> 14: <td align="right"> <%= c.balance %> </td> 15: <td> <%= c.last_issue_dt %> </td>

Maybe I have to shift to the other option. I thought I'd wait to see if you had an approach to make the chosen option work. Maybe it's not worth wasting your time on it.

Best wishes, Richard

4

Hi Curtis,

Thanks again. My excuse (we always need one when we screw up, don't we), is that I'm a Ruby and Rails newbie. So I'm insufficiently sensitive to those pesky little colons.

Incidentally, I copied the code I started with from somewhere (but missed the colons), and that source didn't use any braces to form the hash. So I left them out to see whether it would work without them, wish it did.

I infer from this success that the link_to method's prototype requires a hash and the Ruby interpreter accepts the hash-like elements as components of the needed hash. Just a theory. No need to spend any more time on me.

Again, thank you very much for pushing me along.

Best wishes, Richard

Curtis Summers wrote: