所以我在Gemfile中添加了“gem’paperclip’,：git =>’git：//github.com/thoughtbot/paperclip.git’,: branch =>’rails3’”并启动命令bundle install.

一旦安装了回形针,上传工作正常但不是样式.我看到了修复它的黑客攻击.

# in lib/paperclip/attachment.rb at line 293
def callback which #:nodoc:
  # replace this line...
  # instance.run_callbacks(which,@queued_for_write){|result,obj| result == false }
  # with this:
  instance.run_callbacks(which,@queued_for_write)
end

之后风格还可以,但我无法激活处理器.我的代码是：

has_attached_file                 :image,:default_url => "/images/nopicture.jpg",:styles => { :large   => "800x600>",:cropped => Proc.new { |instance| "#{instance.width}x#{instance.height}>" },:crop    => "300x300>" },:processors => [:cropper]

我的处理器位于RAILS_APP / lib / paperclip_processors / cropper.rb中,包含：

module Paperclip
  class Cropper < Thumbnail
    def transformation_command
      if crop_command  and !skip_crop?
        crop_command + super.sub(/ -crop \S+/,'')
       else
         super
       end
    end

   def crop_command
      target = @attachment.instance
      trans = "";
      trans << " -crop #{target.crop_w}x#{target.crop_h}+#{target.crop_x}+#{target.crop_y}" if target.cropping?
      trans << " -resize \"#{target.width}x#{target.height}\""
      trans
   end

   def skip_crop?
     ["800x600>","300x300>"].include?(@target_geometry.to_s)
   end
 end
end

我的问题是我收到此错误消息：未初始化的常量Paperclip :: Cropper
未加载裁剪的处理器.

有人有想法解决这个问题吗？

有关信息,我的应用程序在rails 2.3.4上正常工作.