CarrierWave Error

carrierwave, ruby-on-rails-3

Solution

CarrierWave doesn't support the `attribute_will_change!` call, at least I ran into this error a few times. Follow the steps from How to: Detect a new file in a mounted uploader at CarrierWave's wiki which provide similar functionality.

Problem

I get an error that looks like this: ``` NoMethodError (undefined method `image_will_change!' for #<Bar:0x24ddda0>): app/controllers/bars_controller.rb:43:in `new' app/controllers/bars_controller.rb:43:in `create' ``` After I click submit for a registration. I am using Carrierwave and have followed the steps to using it, but still have an error.

Original source