I have a model w/ a virtual attribute:
class Campaign < ActiveRecord::Base
def status
if deactivated
return "paused"
else
return "live"
end
end
end
now, in my view, when I access the attribute with campaign.status
, I am getting the proper result. However, when I try to access it like this campaign[:status]
, I get nothing back.
Why is that?
[:status] uses the [] method in Ruby. 'def status' defines a method which shouldn't be mistaken with an ActiveRecord attribute or an virtual attribute (eg attr_reader or attr_accessor). ActiveRecord adds the [] method to your class and makes all the (database) attributes accessible by object[:attr_name] AND object.attr_name(And even object.attributes[:attr_name]).
This is different from how fe Javascript works where obj[:method] is virtually the same as obj.method.
Edit: You should be able to use the attr_accessor if you use them for example in any form:
<%= form.input :status %>
Submitting the form will then set the instance variable @status. If you want to do anything with this before or after saving you can call an before_save or after_save hook:
class Campaign < ActiveRecord::Base
attr_accessible :status
attr_accessor :status
before_save :raise_status
def raise_status
raise @status
end
end
This will throw an error with the value submitted value for status.
Hope this helps.
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