def update
      respond_to do |format|
        if @question_sheet.update_attributes(params[:question_sheet], :without_protection => true)
          format.html { redirect_to admin_question_sheet_path(@question_sheet) }
          format.js 
          format.xml  { head :ok }
        else
          format.html { render :action => "edit" }
          format.js { render :action => "error.js.erb"}
          format.xml  { render :xml => @question_sheet.errors.to_xml }
        end
      end
    end
def update
      respond_to do |format|
        if @question_sheet.update_attributes(params[:question_sheet], :without_protection => true)
          format.html { redirect_to admin_question_sheet_path(@question_sheet) }
          format.js 
          format.xml  { head :ok }
        else
          format.html { render :action => "edit" }
          format.js { render :action => "error.js.erb"}
          format.xml  { render :xml => @question_sheet.errors.to_xml }
        end
      end
    end
save changes to properties panel (label, language)
 PUT /question_sheets/1