Prawn doesn't seem to push layout down when using repeat(:all) - ruby

Question

I am generating a document with data that flows onto each subsequent page, each page has a standard header. However, when I use repeat(:all) to put the header on each page, I find that on every page but the first page, the next content is not being moved down by the size of the header banner I have put on the page.
My code for generating the banner:
class SmartsoftPdf < Prawn::Document
BOX_MARGIN = 30
RHYTHM = 10
INNER_MARGIN = 30
# Colors
#
BLACK = "000000"
LIGHT_GRAY = "F2F2F2"
GRAY = "DDDDDD"
DARK_GRAY = "333333"
BROWN = "A4441C"
ORANGE = "F28157"
LIGHT_GOLD = "FBFBBE"
DARK_GOLD = "EBE389"
BLUE = "08C"
GREEN = "00ff00"
RED = "ff0000"
def show_header(text,date)
header_box do
image "#{Rails.root}/app/assets/images/smart_records_logo_h60.png", :height => 40
draw_text text,
:at => [80,25], :size => 12, :style => :bold, :color => BLUE
draw_text "Date: #{ausDate(date)}",
:at => [bounds.right - 100,bounds.top - 15], :size => 10 if date
end
end
def header_box(&block)
bounding_box([-bounds.absolute_left, cursor + BOX_MARGIN + 8],
:width => bounds.absolute_left + bounds.absolute_right,
:height => BOX_MARGIN*2) do
fill_color LIGHT_GRAY
fill_rectangle([bounds.left, bounds.top],
bounds.right,
bounds.top - bounds.bottom)
fill_color BLACK
move_down(RHYTHM)
indent(BOX_MARGIN, &block)
end
stroke_color GRAY
stroke_horizontal_line(-BOX_MARGIN, bounds.width + BOX_MARGIN, :at => cursor)
stroke_color BLACK
move_down(RHYTHM*4)
end
end
Then within the pdf generation itself I do:
repeat(:all) do
show_header("Custom Report",DateTime.now())
end
However, when I start putting content onto the pages, I expect when the content overflows onto the next page that the content will show up after the header. I'm finding that the header overlaps the content instead.
Here is an image which illustrates the problem: http://i.imgur.com/mSy2but.png
Am I building the header box incorrectly? Do I need to do something additional to make it so that the content which spills into the next page gets pushed down the appropriate amount?

Answer 1

Okay. I have solved this myself. Most recent version of Prawn has a better way to handle this case. When you use repeat(:all) the page is reopened AFTER document creation and your content creation items are then added. This doesn't push the page down. The correct way to add this header to every page is to use the "canvas" method which allows you to operate out of the bounds of the page margin. Use canvas to draw a box at the top of the page, and set the top_margin of the page to push all content below the banner.
canvas do
bounding_box([bounds.left,bounds.top],
:width => bounds.absolute_left + bounds.absolute_right,
:height => BOX_MARGIN*2) do
fill_color LIGHT_GRAY
fill_rectangle([bounds.left, bounds.top],
bounds.right,
bounds.top - bounds.bottom)
fill_color BLACK
move_down(RHYTHM)
indent(BOX_MARGIN, &block)
end
stroke_color GRAY
stroke_horizontal_line(-BOX_MARGIN, bounds.width + BOX_MARGIN, :at => cursor)
stroke_color BLACK
end
at document creation...
def initialize(options = {})
super(:page_layout => :landscape,:top_margin => HEIGHT_OF_BANNER)
end