It took me a while to find this, so, for my own memory I am going to quickly write this up.
I have a view that shows a table of objects (a pretty standard index view). The only issue was I want to sort on one of the columns that actually has data coming not from the main object but an association.
What I discovered is a line in a posting
here that says:
You can define your own custom sort scopes. Define scopes named “sort_by__asc” and “sort_by__desc” and sort_link @search, :name will work as you might expect.So, I have an object of 'info' defined like this:
class Info < ActiveRecord::Base
belongs_to :region
scope :contains_string, lambda {|str| where(:name.matches % "%#{str}%")}
search_methods :contains_string
scope :active, lambda{where(:active => true)}
search_methods :active, :type => :boolean
end
What I found is that you can put this at the end:
scope :sort_by_region_name, lambda{joins(:region).order("regions.name asc")}
search_methods :sort_by_region_name
and then in my view I can do:
<table>
<thead>
<tr>
<td width="25%"><%= sort_link @info_search, :name, "Info" %></td>
<td width="25%"><%= sort_link @info_search, :region_name, "Region" %></td>
<td><%= sort_link @info_search, :active %></td>
</tr>
</thead>
...body info...
</table
And in my controller:
class Admin::InfosController < Admin::BaseController
def index
search = params[:search] || {"meta_sort" => "name.asc"}
@info_search = Info.search(search)
@infos = @linfo_search.paginate(:page => params[:page]||1, :per_page => 15) # load all matching records
end
end
And presto I have an index that
a) default to sorting by name (see the first line of the index method)
b) let's me sort on an associated value
Cool!
