ruby 1.9.2 lambda with paperclip -

i upgrading working app 1.9.2 can't find answer following :

i create asset in controller :

@asset = asset.new(params) 

and in model use lambda dynamically generate styles :

has_attached_file :asset,   :styles => lambda { |attachment| attachment.instance.choose_styles} 

then check value in params so:

def choose_styles   if self.item_name == 'car'     { :small => ["200x200>"], :medium => ["400x400>"], :large => ["700x700>"], :full_screen => ["1000x700>"] }   else     ........  end 

the problem item_name nil in 1.9.2 till after has been run seems set params. works switching 1.8.7

is can see me please ??

thank rick

i know not answer fits question. way, can switch carrierwave (https://github.com/jnicklas/carrierwave). can choose formats in more granular way creating various versions , nesting them.

as example, ipothetic assetuploader be:

... version :thumb_200x200   process :resize_to_fill => [200,200] end  version :big_600x600   ... end ... version :car, :if => in_category(:car)?   version :thumb_200x200   version :another_etc end ... protected   def in_category?(name)     model.item_name.downcase == name.to_s   end ... 

this example of code, adjust needs ;)

cheers, a.