Rails/Prawn:如何在Prawn类中使用rails helpers？

Question

我正在尝试rails 3.2在prawn类中使用帮助器,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.

Answer 1

您必须ActionView::Helpers::NumberHelper在您的prawn文档类中明确包含(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

Answer 2

只需传递view_context给Prawn子类初始化程序.

def initialize(quote, view_context)
  super()
  @view = view_context
end

在控制器中,更改为:

QuotePdf.new(@quote, view_context)

然后在Prawn子类中,这将起作用:

@view.number_with_precision(quote.sum)

Answer 3

如果iafonov解决方案不起作用,您可能只需要不包含NumberHelper前缀.