ruby-on-rails – Rails / Prawn：如何在Prawn类中使用rails helper？

我正在尝试在一个虾类中使用rails 3.2助手,但是rails会抛出：

undefined method `number_with_precision' for #<QuotePdf:0x83d4188>

虾类

class QuotePdf < Prawn::Document
  def initialize(quote)
    super()

    text "sum: #{number_with_precision(quote.sum)}"
  end
end

调节器

def show
  @quote = current_user.company.quotes.where(:id => params[:id]).first
  head :unauthorized and return unless @quote

  respond_with @quote,:layout => !params[:_pjax] do |format|
    format.pdf do
      send_data QuotePdf.new(@quote).render,filename: "Devis-#{@quote.date_emission.strftime("%d/%m/%Y")}.pdf",type: "application/pdf"
    end
  end
end

谢谢你的帮助.

解决方法

您必须在您的prawn文档类中显式包含ActionView :: Helpers :: NumberHelper(或任何其他帮助程序类/模块).

class QuotePdf < Prawn::Document
  include ActionView::Helpers::NumberHelper # <-

  def initialize(quote)
    super()

    text "sum: #{number_with_precision(quote.sum)}"
  end
end