How do you do this in Rails?

rubyonrails-talk
1

I have a model ("Ups") and a corresponding controller ("UpsController"). The Ups model has a link to my "channels" toble through channel_id

Everything I am going to do in the given views for Ups have to do with using those ups from a selected channel. Thus, I am putting a partial at the top of the views, with a select box to choose the channels:

<div id="uplognavlist"> <% form_for :ups, :html => {:name => 'channelsform'},:url=>{ :action =>"newchannel", :controller =>"ups"} do |f| %>     <%= f.label :channel_id %>   <%= select("channel", "channel_id", Channel.find(:all, :order => 'channel ASC', :conditions => ['deleted=0']).collect {|p| [ p.channel, p.id ]}, {:include_blank => true}) %>       <%= f.submit "Change" , :class=>'button' %> <% end %>    <%= links_for_uplog %> </div>

My question is, within my UpsController.newchannel(), how do I access the calue of the channel_id that has been selected in the form submission?

Incidentally, if you look at the erb code I put above, there is a line feed that gets inserted after the submit button, before the next section " links_for_uplog " within the div. How can I not have that?

Thanks, Janna

2

Hi Janna,

First, you shouldn't be calling Channel.find(:all, :order => 'channel ASC', :conditions => ['deleted=0']).collect {|p| [ p.channel, p.id ]}

I'd add a named scope to the Channel model like so:

  named_scope :not_deleted, :conditions => {:deleted => false }, :order => 'channel ASC'

And then in the controller: @channels = Channel.not_deleted

Then in your view: <%= f.select :channel_id, @channels %>

The standard here would be to create the new Ups in a method called create. By using form_for on a new record rails will automatically know to post to an action called create so, unless you have a good reason not to, I'd recommend calling your controller method "create" and letting Rails behave the way it wants to.

which 'line feed' do you want to remove?

Gavin

3

Sorry, to answer the original question:

> My question is, within my UpsController.newchannel(), how do I access > the calue of the channel_id that has been selected in the form > submission?

When rails posts a form to an action, all of the info from the form will be included in a hash called params.

In this case the hash would contain: :ups => {:channel_id => value }

so to access it you'd use params[:ups][:channel_id]

4

Gavin,

Thank you. But suppose I didn't use a named scope -- in that case, how then could I refer to it in my controller? (though I will follow your advice and use the named scope, I need to know the other way also).

Also, between:

  <%= f.submit "Change" , :class=>'button' %> <% end %>         <%= links_for_uplog %>

it seems a line feed occurs......the <%= links_for_uplog %> is not immediately to the right as I would like it to be (in <%= links_for_uplog %>,

the rendered html appears as (copying from firebug): <div id="uplognavlist"> <form name="channelsform" method="post" action="/ups/newchannel"> <div style="margin: 0pt; padding: 0pt;"> <input type="hidden" value="Ty9TBUArgAPxtLuvGL48Sg1uYbzlZWmSJL2dsWuL +YQ=" name="authenticity_token"/> </div> <label for="ups_channel_id">Channel</label> <select id="channel_channel_id" onchange="document.channelsform.submit ();" name="channel[channel_id]"> <option value=""/> <option value="1">ggriptest</option> </select> </form> <a title="Non-Automatic Change Log" style="float: right;" href="/ audits/list?update=UpLogBody">Audit</a> <a title="Add or Remove Associates" style="float: right;" href="/ups/ hotwire?update=UpLogBody">Hotwire</a> <a title="Show Uplog" style="float: right;" href="/ups/uplog? update=UpLogBody">Uplog</a> </div>

It appears that after either </select> or </form> there is some kind of a line feed in the display.

Can you please answer Me those two questions Gavin? Thank You, Janna

5

Try using <%- end -%> instead of <% end %> at the of the form. That should remove the line feeds and white space.

A lot of rails coders wouldn't use the named scope here. I always try to keep as much of this sort of logic in the model but you could also simply use 'find' in the controller:

@channels = Channel.all( :conditions => { :deleted => false }, :order => 'channel ASC' ).collect { |p| p.name, p.id }

also check out collection_select: http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html#M001910

I think this might be more appropriate for you in this instance:

<%= f.collection_select :channel_id, @channels, :id, :prompt => true %>

Hope that helps?

Gavin

6

damn - sorry that should be: <%= f.collection_select :channel_id, @channels, :id, :channel, :prompt => true %>

missed out the text_method param

Gavin

http://handyrailsitps.com

7

Gavin,

Sorry to beat the dead horse, but I still need to know how to access the channel_id given the way I initially posted the code. Can you show me that? -Janna

8

Okay - I'm assuming the action your form posts to is newchannel and you want to access the input from the form in that method? In which case:

@channel_id_you_want = params[:ups][:channel_id]

That should work?

Gavin

9

Ahh, right...that's it. God, I just couldn't get that -- ok, off to do it the right way that you showed me! -Janna.