Class: Prawn::Document

Inherits:
Object
  • Object
show all
Includes:
PDF::Core::Annotations, PDF::Core::Destinations, Security, Graphics, Images, SoftMask, Stamp, Text, TransformationStack
Defined in:
lib/prawn/document.rb,
lib/prawn/grid.rb,
lib/prawn/font.rb,
lib/prawn/outline.rb,
lib/prawn/repeater.rb,
lib/prawn/security.rb,
lib/prawn/document/span.rb,
lib/prawn/document/internals.rb,
lib/prawn/document/column_box.rb,
lib/prawn/document/bounding_box.rb

Overview

The Prawn::Document class is how you start creating a PDF document.

There are three basic ways you can instantiate PDF Documents in Prawn, they are through assignment, implicit block or explicit block. Below is an exmple of each type, each example does exactly the same thing, makes a PDF document with all the defaults and puts in the default font “Hello There” and then saves it to the current directory as “example.pdf”

For example, assignment can be like this:

pdf = Prawn::Document.new
pdf.text "Hello There"
pdf.render_file "example.pdf"

Or you can do an implied block form:

Prawn::Document.generate "example.pdf" do
  text "Hello There"
end

Or if you need to access a variable outside the scope of the block, the explicit block form:

words = "Hello There"
Prawn::Document.generate "example.pdf" do |pdf|
  pdf.text words
end

Usually, the block forms are used when you are simply creating a PDF document that you want to immediately save or render out.

See the new and generate methods for further details on the above.

Defined Under Namespace

Modules: Security Classes: BoundingBox, ColumnBox, Grid, GridBox, MultiBox

Extension API collapse

VALID_OPTIONS =

NOTE: We probably need to rethink the options validation system, but this constant temporarily allows for extensions to modify the list.

[:page_size, :page_layout, :margin, :left_margin,
:right_margin, :top_margin, :bottom_margin, :skip_page_creation,
:compress, :background, :info,
:text_formatter, :print_scaling]

Constants included from Graphics

Graphics::KAPPA

Constants included from Graphics::JoinStyle

Graphics::JoinStyle::JOIN_STYLES

Constants included from Graphics::CapStyle

Graphics::CapStyle::CAP_STYLES

Stable Attributes collapse

Extension Attributes collapse

Experimental API collapse

Stable API collapse

Extension API collapse

Methods included from TransformationStack

#add_to_transformation_stack, #current_transformation_matrix_with_translation, #restore_transformation_stack, #save_transformation_stack

Methods included from SoftMask

#soft_mask

Methods included from Stamp

#create_stamp, #stamp, #stamp_at

Methods included from Images

#image

Methods included from Graphics

#circle, #close_and_stroke, #close_path, #curve, #curve_to, #ellipse, #fill, #fill_and_stroke, #horizontal_line, #horizontal_rule, #line, #line_to, #line_width, #line_width=, #move_to, #polygon, #rectangle, #rounded_polygon, #rounded_rectangle, #rounded_vertex, #stroke, #stroke_axis, #stroke_bounds, #vertical_line

Methods included from Graphics::Patterns

#fill_gradient, #stroke_gradient

Methods included from Graphics::Transformation

#rotate, #scale, #transformation_matrix, #translate

Methods included from Graphics::Transparency

#transparent

Methods included from Graphics::JoinStyle

#join_style

Methods included from Graphics::CapStyle

#cap_style

Methods included from Graphics::Dash

#dash, #dashed?, #undash

Methods included from Graphics::Color

#fill_color, hex2rgb, rgb2hex, #stroke_color

Methods included from Graphics::BlendMode

#blend_mode

Methods included from Text

#draw_text, #draw_text!, #formatted_text, #height_of, #height_of_formatted, #text, #text_box

Methods included from Text::Formatted

#formatted_text_box

Methods included from Security

#encrypt_document, encrypt_string

Constructor Details

#initialize(options = {}, &block) ⇒ Document

Creates a new PDF Document. The following options are available (with the default values marked in [])

:page_size

One of the PDF::Core::PageGeometry sizes [LETTER]

:page_layout

Either :portrait or :landscape

:margin

Sets the margin on all sides in points [0.5 inch]

:left_margin

Sets the left margin in points [0.5 inch]

:right_margin

Sets the right margin in points [0.5 inch]

:top_margin

Sets the top margin in points [0.5 inch]

:bottom_margin

Sets the bottom margin in points [0.5 inch]

:skip_page_creation

Creates a document without starting the first page [false]

:compress

Compresses content streams before rendering them [false]

:background

An image path to be used as background on all pages [nil]

:background_scale

Backgound image scale [1] [nil]

:info

Generic hash allowing for custom metadata properties [nil]

:text_formatter: The text formatter to use for :inline_formatted text [Prawn::Text::Formatted::Parser]

Setting e.g. the :margin to 100 points and the :left_margin to 50 will result in margins of 100 points on every side except for the left, where it will be 50.

The :margin can also be an array much like CSS shorthand:

# Top and bottom are 20, left and right are 100.
:margin => [20, 100]
# Top is 50, left and right are 100, bottom is 20.
:margin => [50, 100, 20]
# Top is 10, right is 20, bottom is 30, left is 40.
:margin => [10, 20, 30, 40]

Additionally, :page_size can be specified as a simple two value array giving the width and height of the document you need in PDF Points.

Usage:

# New document, US Letter paper, portrait orientation
pdf = Prawn::Document.new

# New document, A4 paper, landscaped
pdf = Prawn::Document.new(:page_size => "A4", :page_layout => :landscape)

# New document, Custom size
pdf = Prawn::Document.new(:page_size => [200, 300])

# New document, with background
pdf = Prawn::Document.new(:background => "#{Prawn::DATADIR}/images/pigs.jpg")


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# File 'lib/prawn/document.rb', line 192

def initialize(options = {}, &block)
  options = options.dup

  Prawn.verify_options VALID_OPTIONS, options

  # need to fix, as the refactoring breaks this
  # raise NotImplementedError if options[:skip_page_creation]

  self.class.extensions.reverse_each { |e| extend e }
  self.state = PDF::Core::DocumentState.new(options)
  self.state.populate_pages_from_store(self)
  renderer.min_version(state.store.min_version) if state.store.min_version

  renderer.min_version(1.6) if options[:print_scaling] == :none

  @background = options[:background]
  @background_scale = options[:background_scale] || 1
  @font_size  = 12

  @bounding_box  = nil
  @margin_box    = nil

  @page_number = 0

  @text_formatter = options.delete(:text_formatter) || Text::Formatted::Parser

  options[:size] = options.delete(:page_size)
  options[:layout] = options.delete(:page_layout)

  initialize_first_page(options)

  @bounding_box = @margin_box

  if block
    block.arity < 1 ? instance_eval(&block) : block[self]
  end
end

Instance Attribute Details

#margin_boxObject

Returns the value of attribute margin_box



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# File 'lib/prawn/document.rb', line 104

def margin_box
  @margin_box
end

#marginsObject (readonly)

Returns the value of attribute margins



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# File 'lib/prawn/document.rb', line 105

def margins
  @margins
end

#page_numberObject

Returns the value of attribute page_number



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# File 'lib/prawn/document.rb', line 106

def page_number
  @page_number
end

#text_formatterObject

Returns the value of attribute text_formatter



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# File 'lib/prawn/document.rb', line 110

def text_formatter
  @text_formatter
end

#yObject

Returns the value of attribute y



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# File 'lib/prawn/document.rb', line 105

def y
  @y
end

Class Method Details

.extensionsObject

Any module added to this array will be included into instances of Prawn::Document at the per-object level. These will also be inherited by any subclasses.

Example:

module MyFancyModule

  def party!
    text "It's a big party!"
  end

end

Prawn::Document.extensions << MyFancyModule

Prawn::Document.generate("foo.pdf") do
  party!
end


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# File 'lib/prawn/document.rb', line 93

def self.extensions
  @extensions ||= []
end

.generate(filename, options = {}, &block) ⇒ Object

Creates and renders a PDF document.

When using the implicit block form, Prawn will evaluate the block within an instance of Prawn::Document, simplifying your syntax. However, please note that you will not be able to reference variables from the enclosing scope within this block.

# Using implicit block form and rendering to a file
Prawn::Document.generate "example.pdf" do
  # self here is set to the newly instantiated Prawn::Document
  # and so any variables in the outside scope are unavailable
  font "Times-Roman"
  draw_text "Hello World", :at => [200,720], :size => 32
end

If you need to access your local and instance variables, use the explicit block form shown below. In this case, Prawn yields an instance of PDF::Document and the block is an ordinary closure:

# Using explicit block form and rendering to a file
content = "Hello World"
Prawn::Document.generate "example.pdf" do |pdf|
  # self here is left alone
  pdf.font "Times-Roman"
  pdf.draw_text content, :at => [200,720], :size => 32
end


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# File 'lib/prawn/document.rb', line 141

def self.generate(filename, options = {}, &block)
  pdf = new(options, &block)
  pdf.render_file(filename)
end

Instance Method Details

#bounding_box(pt, *args, &block) ⇒ Object

:call-seq:

bounding_box(point, options={}, &block)

A bounding box serves two important purposes:

  • Provide bounds for flowing text, starting at a given point

  • Translate the origin (0,0) for graphics primitives

A point and :width must be provided. :height is optional. (See stretchyness below)

Positioning

Bounding boxes are positioned relative to their top left corner and the width measurement is towards the right and height measurement is downwards.

Usage:

  • Bounding box 100pt x 100pt in the absolute bottom left of the containing box:

    pdf.bounding_box(, :width => 100, :height => 100)

    stroke_bounds
    

    end

  • Bounding box 200pt x 400pt high in the center of the page:

    x_pos = ((bounds.width / 2) - 150) y_pos = ((bounds.height / 2) + 200) pdf.bounding_box([x_pos, y_pos], :width => 300, :height => 400) do

    stroke_bounds
    

    end

Flowing Text

When flowing text, the usage of a bounding box is simple. Text will begin at the point specified, flowing the width of the bounding box. After the block exits, the cursor position will be moved to the bottom of the bounding box (y - height). If flowing text exceeds the height of the bounding box, the text will be continued on the next page, starting again at the top-left corner of the bounding box.

Usage:

pdf.bounding_box([100,500], :width => 100, :height => 300) do
  pdf.text "This text will flow in a very narrow box starting" +
   "from [100,500]. The pointer will then be moved to [100,200]" +
   "and return to the margin_box"
end

Note, this is a low level tool and is designed primarily for building other abstractions. If you just need to flow text on the page, you will want to look at span() and text_box() instead

Translating Coordinates

When translating coordinates, the idea is to allow the user to draw relative to the origin, and then translate their drawing to a specified area of the document, rather than adjust all their drawing coordinates to match this new region.

Take for example two triangles which share one point, drawn from the origin:

pdf.polygon [0,250], [0,0], [150,100]
pdf.polygon [100,0], [150,100], [200,0]

It would be easy enough to translate these triangles to another point, e.g [200,200]

pdf.polygon [200,450], [200,200], [350,300]
pdf.polygon [300,200], [350,300], [400,200]

However, each time you want to move the drawing, you'd need to alter every point in the drawing calls, which as you might imagine, can become tedious.

If instead, we think of the drawing as being bounded by a box, we can see that the image is 200 points wide by 250 points tall.

To translate it to a new origin, we simply select a point at (x,y+height)

Using the [200,200] example:

pdf.bounding_box([200,450], :width => 200, :height => 250) do
  pdf.stroke do
    pdf.polygon [0,250], [0,0], [150,100]
    pdf.polygon [100,0], [150,100], [200,0]
  end
end

Notice that the drawing is still relative to the origin. If we want to move this drawing around the document, we simply need to recalculate the top-left corner of the rectangular bounding-box, and all of our graphics calls remain unmodified.

Nesting Bounding Boxes

At the top level, bounding boxes are specified relative to the document's margin_box (which is itself a bounding box). You can also nest bounding boxes, allowing you to build components which are relative to each other

Usage:

pdf.bounding_box([200,450], :width => 200, :height => 250) do
  pdf.stroke_bounds   # Show the containing bounding box
  pdf.bounding_box([50,200], :width => 50, :height => 50) do
    # a 50x50 bounding box that starts 50 pixels left and 50 pixels down
    # the parent bounding box.
    pdf.stroke_bounds
  end
end

Stretchyness

If you do not specify a height to a bounding box, it will become stretchy and its height will be calculated automatically as you stretch the box downwards.

pdf.bounding_box([100,400], :width => 400) do
  pdf.text("The height of this box is #{pdf.bounds.height}")
  pdf.text('this is some text')
  pdf.text('this is some more text')
  pdf.text('and finally a bit more')
  pdf.text("Now the height of this box is #{pdf.bounds.height}")
end

Absolute Positioning

If you wish to position the bounding boxes at absolute coordinates rather than relative to the margins or other bounding boxes, you can use canvas()

pdf.bounding_box([50,500], :width => 200, :height => 300) do
  pdf.stroke_bounds
  pdf.canvas do
    Positioned outside the containing box at the 'real' (300,450)
    pdf.bounding_box([300,450], :width => 200, :height => 200) do
      pdf.stroke_bounds
    end
  end
end

Of course, if you use canvas, you will be responsible for ensuring that you remain within the printable area of your document.



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# File 'lib/prawn/document/bounding_box.rb', line 158

def bounding_box(pt, *args, &block)
  init_bounding_box(block) do |parent_box|
    pt = map_to_absolute(pt)
    @bounding_box = BoundingBox.new(self, parent_box, pt, *args)
  end
end

#boundsObject

The bounds method returns the current bounding box you are currently in, which is by default the box represented by the margin box on the document itself. When called from within a created bounding_box block, the box defined by that call will be returned instead of the document margin box.

Another important point about bounding boxes is that all x and y measurements within a bounding box code block are relative to the bottom left corner of the bounding box.

For example:

Prawn::Document.new do
  # In the default "margin box" of a Prawn document of 0.5in along each edge

  # Draw a border around the page (the manual way)
  stroke do
    line(bounds.bottom_left, bounds.bottom_right)
    line(bounds.bottom_right, bounds.top_right)
    line(bounds.top_right, bounds.top_left)
    line(bounds.top_left, bounds.bottom_left)
  end

  # Draw a border around the page (the easy way)
  stroke_bounds
end


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# File 'lib/prawn/document.rb', line 398

def bounds
  @bounding_box
end

#bounds=(bounding_box) ⇒ Object

Sets Document#bounds to the BoundingBox provided. See above for a brief description of what a bounding box is. This function is useful if you really need to change the bounding box manually, but usually, just entering and exiting bounding box code blocks is good enough.



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# File 'lib/prawn/document.rb', line 414

def bounds=(bounding_box)
  @bounding_box = bounding_box
end

#canvas(&block) ⇒ Object

A shortcut to produce a bounding box which is mapped to the document's absolute coordinates, regardless of how things are nested or margin sizes.

pdf.canvas do
  pdf.line pdf.bounds.bottom_left, pdf.bounds.top_right
end


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# File 'lib/prawn/document/bounding_box.rb', line 172

def canvas(&block)
  init_bounding_box(block, :hold_position => true) do |_|
    # Canvas bbox acts like margin_box in that its parent bounds are unset.
    @bounding_box = BoundingBox.new(
      self, nil, [0, page.dimensions[3]],
      :width => page.dimensions[2],
      :height => page.dimensions[3]
    )
  end
end

#column_box(*args, &block) ⇒ Object

A column box is a bounding box with the additional property that when text flows past the bottom, it will wrap first to another column on the same page, and only flow to the next page when all the columns are filled.

column_box accepts the same parameters as bounding_box, as well as the number of :columns and a :spacer (in points) between columns. If resetting the top margin is desired on a new page (e.g. to allow for initial page wide column titles) the option :reflow_margins => true can be set.

Defaults are :columns = 3, :spacer = font_size, and :reflow_margins => false

Under PDF::Writer, “spacer” was known as “gutter”



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# File 'lib/prawn/document/column_box.rb', line 30

def column_box(*args, &block)
  init_column_box(block) do |parent_box|
    map_to_absolute!(args[0])
    @bounding_box = ColumnBox.new(self, parent_box, *args)
  end
end

#cursorObject

The current y drawing position relative to the innermost bounding box, or to the page margins at the top level.



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# File 'lib/prawn/document.rb', line 320

def cursor
  y - bounds.absolute_bottom
end

#define_grid(options = {}) ⇒ Object

Defines the grid system for a particular document. Takes the number of rows and columns and the width to use for the gutter as the keys :rows, :columns, :gutter, :row_gutter, :column_gutter

Note that a completely new grid object is built each time define_grid() is called. This means that all subsequent calls to grid() will use the newly defined Grid object – grids are not nestable like bounding boxes are.



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# File 'lib/prawn/grid.rb', line 22

def define_grid(options = {})
  @boxes = nil
  @grid = Grid.new(self, options)
end

#floatObject

Executes a block and then restores the original y position. If new pages were created during this block, it will teleport back to the original page when done.

pdf.text "A"

pdf.float do
  pdf.move_down 100
  pdf.text "C"
end

pdf.text "B"


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# File 'lib/prawn/document.rb', line 343

def float
  original_page = page_number
  original_y = y
  yield
  go_to_page(original_page) unless page_number == original_page
  self.y = original_y
end

#font(name = nil, options = {}) ⇒ Object

Without arguments, this returns the currently selected font. Otherwise, it sets the current font. When a block is used, the font is applied transactionally and is rolled back when the block exits.

Prawn::Document.generate("font.pdf") do
  text "Default font is Helvetica"

  font "Times-Roman"
  text "Now using Times-Roman"

  font("DejaVuSans.ttf") do
    text "Using TTF font from file DejaVuSans.ttf"
    font "Courier", :style => :bold
    text "You see this in bold Courier"
  end

  text "Times-Roman, again"
end

The :name parameter must be a string. It can be one of the 14 built-in fonts supported by PDF, or the location of a TTF file. The Font::AFM::BUILT_INS array specifies the valid built in font values.

If a ttf font is specified, the glyphs necessary to render your document will be embedded in the rendered PDF. This should be your preferred option in most cases. It will increase the size of the resulting file, but also make it more portable.

The options parameter is an optional hash providing size and style. To use the :style option you need to map those font styles to their respective font files. See font_families for more information.



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# File 'lib/prawn/font.rb', line 50

def font(name = nil, options = {})
  return((defined?(@font) && @font) || font("Helvetica")) if name.nil?

  if state.pages.empty? && !state.page.in_stamp_stream?
    fail Prawn::Errors::NotOnPage
  end

  new_font = find_font(name.to_s, options)

  if block_given?
    save_font do
      set_font(new_font, options[:size])
      yield
    end
  else
    set_font(new_font, options[:size])
  end

  @font
end

#font_familiesObject

Hash that maps font family names to their styled individual font names.

To add support for another font family, append to this hash, e.g:

pdf.font_families.update(
 "MyTrueTypeFamily" => { :bold        => "foo-bold.ttf",
                         :italic      => "foo-italic.ttf",
                         :bold_italic => "foo-bold-italic.ttf",
                         :normal      => "foo.ttf" })

This will then allow you to use the fonts like so:

pdf.font("MyTrueTypeFamily", :style => :bold)
pdf.text "Some bold text"
pdf.font("MyTrueTypeFamily")
pdf.text "Some normal text"

This assumes that you have appropriate TTF fonts for each style you wish to support.

By default the styles :bold, :italic, :bold_italic, and :normal are defined for fonts “Courier”, “Times-Roman” and “Helvetica”. When defining your own font families, you can map any or all of these styles to whatever font files you'd like.



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# File 'lib/prawn/font.rb', line 170

def font_families
  @font_families ||= {}.merge!(
    "Courier"     => { :bold        => "Courier-Bold",
                       :italic      => "Courier-Oblique",
                       :bold_italic => "Courier-BoldOblique",
                       :normal      => "Courier" },

    "Times-Roman" => { :bold         => "Times-Bold",
                       :italic       => "Times-Italic",
                       :bold_italic  => "Times-BoldItalic",
                       :normal       => "Times-Roman" },

    "Helvetica"   => { :bold         => "Helvetica-Bold",
                       :italic       => "Helvetica-Oblique",
                       :bold_italic  => "Helvetica-BoldOblique",
                       :normal       => "Helvetica" }
  )
end

#font_registryObject

Hash of Font objects keyed by names



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# File 'lib/prawn/font.rb', line 249

def font_registry #:nodoc:
  @font_registry ||= {}
end

#font_size(points = nil) ⇒ Object

When called with no argument, returns the current font size.

When called with a single argument but no block, sets the current font size. When a block is used, the font size is applied transactionally and is rolled back when the block exits. You may still change the font size within a transactional block for individual text segments, or nested calls to font_size.

Prawn::Document.generate("font_size.pdf") do
  font_size 16
  text "At size 16"

  font_size(10) do
    text "At size 10"
    text "At size 6", :size => 6
    text "At size 10"
  end

  text "At size 16"
end

When called without an argument, this method returns the current font size.



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# File 'lib/prawn/font.rb', line 97

def font_size(points = nil)
  return @font_size unless points
  size_before_yield = @font_size
  @font_size = points
  block_given? ? yield : return
  @font_size = size_before_yield
end

#font_size=(size) ⇒ Object

Sets the font size



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# File 'lib/prawn/font.rb', line 106

def font_size=(size)
  font_size(size)
end

#go_to_page(k) ⇒ Object

Re-opens the page with the given (1-based) page number so that you can draw on it.

See Prawn::Document#number_pages for a sample usage of this capability.



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# File 'lib/prawn/document.rb', line 305

def go_to_page(k)
  @page_number = k
  state.page = state.pages[k - 1]
  generate_margin_box
  @y = @bounding_box.absolute_top
end

#grid(*args) ⇒ Object

A method that can either be used to access a particular grid on the page or work with the grid system directly.

@pdf.grid                 # Get the Grid directly
@pdf.grid([0,1])          # Get the GridBox at [0,1]
@pdf.grid([0,1], [1,2])   # Get a multi-box spanning from [0,1] to [1,2]


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# File 'lib/prawn/grid.rb', line 34

def grid(*args)
  @boxes ||= {}
  return @boxes[args] if @boxes[args]

  if args.empty?
    @boxes[args] = @grid
  else
    g1, g2 = args

    if g1.class == Array && g2.class == Array && g1.length == 2 && g2.length == 2
      @boxes[args] = multi_box(single_box(*g1), single_box(*g2))
    else
      @boxes[args] = single_box(g1, g2)
    end
  end

  @boxes[args]
end

#indent(left, right = 0, &block) ⇒ Object

Indents the specified number of PDF points for the duration of the block

pdf.text "some text"
pdf.indent(20) do
  pdf.text "This is indented 20 points"
end
pdf.text "This starts 20 points left of the above line " +
         "and is flush with the first line"
pdf.indent 20, 20 do
  pdf.text "This line is indented on both sides."
end


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# File 'lib/prawn/document.rb', line 485

def indent(left, right = 0, &block)
  bounds.indent(left, right, &block)
end

#initialize_first_page(options) ⇒ Object



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# File 'lib/prawn/document.rb', line 631

def initialize_first_page(options)
  if options[:skip_page_creation]
    start_new_page(options.merge(:orphan => true))
  else
    start_new_page(options)
  end
end

#move_cursor_to(new_y) ⇒ Object

Moves to the specified y position in relative terms to the bottom margin.



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# File 'lib/prawn/document.rb', line 326

def move_cursor_to(new_y)
  self.y = new_y + bounds.absolute_bottom
end

#move_down(n) ⇒ Object

Moves down the document by n points relative to the current position inside the current bounding box.



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# File 'lib/prawn/document.rb', line 428

def move_down(n)
  self.y -= n
end

#move_up(n) ⇒ Object

Moves up the document by n points relative to the current position inside the current bounding box.



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# File 'lib/prawn/document.rb', line 421

def move_up(n)
  self.y += n
end

#number_pages(string, options = {}) ⇒ Object

Places a text box on specified pages for page numbering. This should be called towards the end of document creation, after all your content is already in place. In your template string, <page> refers to the current page, and <total> refers to the total amount of pages in the document. Page numbering should occur at the end of your Prawn::Document.generate block because the method iterates through existing pages after they are created.

Parameters are:

string

Template string for page number wording. Should include '<page>' and, optionally, '<total>'.

options

A hash for page numbering and text box options.

:page_filter

A filter to specify which pages to place page numbers on. Refer to the method 'page_match?'

:start_count_at

The starting count to increment pages from.

:total_pages

If provided, will replace <total> with the value given. Useful to override the total number of pages when using the start_count_at option.

:color

Text fill color.

Please refer to Prawn::Text::text_box for additional options concerning text
formatting and placement.

Example: Print page numbers on every page except for the first. Start counting from

       five.

Prawn::Document.generate("page_with_numbering.pdf") do
  number_pages "<page> in a total of <total>",
                                       {:start_count_at => 5,
                                        :page_filter => lambda{ |pg| pg != 1 },
                                        :at => [bounds.right - 50, 0],
                                        :align => :right,
                                        :size => 14}
end


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# File 'lib/prawn/document.rb', line 524

def number_pages(string, options = {})
  opts = options.dup
  start_count_at = opts.delete(:start_count_at).to_i

  if opts.key?(:page_filter)
    page_filter = opts.delete(:page_filter)
  else
    page_filter = :all
  end

  total_pages = opts.delete(:total_pages)
  txtcolor = opts.delete(:color)
  # An explicit height so that we can draw page numbers in the margins
  opts[:height] = 50 unless opts.key?(:height)

  start_count = false
  pseudopage = 0
  (1..page_count).each do |p|
    unless start_count
      pseudopage = case start_count_at
                   when 0
                     1
                   else
                     start_count_at.to_i
                   end
    end
    if page_match?(page_filter, p)
      go_to_page(p)
      # have to use fill_color here otherwise text reverts back to default fill color
      fill_color txtcolor unless txtcolor.nil?
      total_pages = total_pages.nil? ? page_count : total_pages
      str = string.gsub("<page>", "#{pseudopage}").gsub("<total>", "#{total_pages}")
      text_box str, opts
      start_count = true  # increment page count as soon as first match found
    end
    pseudopage += 1 if start_count
  end
end

#outlineObject

Lazily instantiates a Prawn::Outline object for document. This is used as point of entry to methods to build the outline tree for a document's table of contents.



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# File 'lib/prawn/outline.rb', line 9

def outline
  @outline ||= Outline.new(self)
end

#pad(y) ⇒ Object

Moves down the document by y, executes a block, then moves down the document by y again.

pdf.text "some text"
pdf.pad(100) do
  pdf.text "This is 100 points below the previous line of text"
end
pdf.text "This is 100 points below the previous line of text"


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# File 'lib/prawn/document.rb', line 467

def pad(y)
  move_down(y)
  yield
  move_down(y)
end

#pad_bottom(y) ⇒ Object

Executes a block then moves down the document

pdf.text "some text"
pdf.pad_bottom(100) do
  pdf.text "This text appears right below the previous line of text"
end
pdf.text "This is 100 points below the previous line of text"


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# File 'lib/prawn/document.rb', line 453

def pad_bottom(y)
  yield
  move_down(y)
end

#pad_top(y) ⇒ Object

Moves down the document and then executes a block.

pdf.text "some text"
pdf.pad_top(100) do
  pdf.text "This is 100 points below the previous line of text"
end
pdf.text "This text appears right below the previous line of text"


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# File 'lib/prawn/document.rb', line 440

def pad_top(y)
  move_down(y)
  yield
end

#page_countObject

Returns the number of pages in the document

pdf = Prawn::Document.new
pdf.page_count #=> 1
3.times { pdf.start_new_page }
pdf.page_count #=> 4


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# File 'lib/prawn/document.rb', line 296

def page_count
  state.page_count
end

#page_match?(page_filter, page_number) ⇒ Boolean

Provides a way to execute a block of code repeatedly based on a page_filter.

Available page filters are:

:all         repeats on every page
:odd         repeats on odd pages
:even        repeats on even pages
some_array   repeats on every page listed in the array
some_range   repeats on every page included in the range
some_lambda  yields page number and repeats for true return values

Returns:

  • (Boolean)


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# File 'lib/prawn/document.rb', line 602

def page_match?(page_filter, page_number)
  case page_filter
  when :all
    true
  when :odd
    page_number.odd?
  when :even
    page_number.even?
  when Range, Array
    page_filter.include?(page_number)
  when Proc
    page_filter.call(page_number)
  end
end

#render(*a, &b) ⇒ Object

Renders the PDF document to string. Pass an open file descriptor to render to file.



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# File 'lib/prawn/document.rb', line 354

def render(*a, &b)
  (1..page_count).each do |i|
    go_to_page i
    repeaters.each { |r| r.run(i) }
  end

  renderer.render(*a, &b)
end

#render_file(filename) ⇒ Object

Renders the PDF document to file.

pdf.render_file "foo.pdf"


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# File 'lib/prawn/document.rb', line 367

def render_file(filename)
  File.open(filename, "wb") { |f| render(f) }
end

#repeat(page_filter, options = {}, &block) ⇒ Object

Provides a way to execute a block of code repeatedly based on a page_filter. Since Stamp is used under the hood, this method is very space efficient.

Available page filters are:

:all        -- repeats on every page
:odd        -- repeats on odd pages
:even       -- repeats on even pages
some_array  -- repeats on every page listed in the array
some_range  -- repeats on every page included in the range
some_lambda -- yields page number and repeats for true return values

Also accepts an optional second argument for dynamic content which executes the code in the context of the filtered pages without using a Stamp.

Example:

Prawn::Document.generate("repeat.pdf", :skip_page_creation => true) do

  repeat :all do
    draw_text "ALLLLLL", :at => bounds.top_left
  end

  repeat :odd do
    draw_text "ODD", :at => [0,0]
  end

  repeat :even do
    draw_text "EVEN", :at => [0,0]
  end

  repeat [1,2] do
    draw_text "[1,2]", :at => [100,0]
  end

  repeat 2..4 do
    draw_text "2..4", :at => [200,0]
  end

  repeat(lambda { |pg| pg % 3 == 0 }) do
    draw_text "Every third", :at => [250, 20]
  end

  10.times do
    start_new_page
    draw_text "A wonderful page", :at => [400,400]
  end

  repeat(:all, :dynamic => true) do
    text page_number, :at => [500, 0]
  end

end


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# File 'lib/prawn/repeater.rb', line 77

def repeat(page_filter, options = {}, &block)
  repeaters << Prawn::Repeater.new(self, page_filter, !!options[:dynamic], &block)
end

#save_fontObject

Saves the current font, and then yields. When the block finishes, the original font is restored.



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# File 'lib/prawn/font.rb', line 202

def save_font
  @font ||= find_font("Helvetica")
  original_font = @font
  original_size = @font_size

  yield
ensure
  set_font(original_font, original_size) if original_font
end

#set_font(font, size = nil) ⇒ Object

Sets the font directly, given an actual Font object and size.



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# File 'lib/prawn/font.rb', line 194

def set_font(font, size = nil) # :nodoc:
  @font = font
  @font_size = size if size
end

#span(width, options = {}) ⇒ Object

A span is a special purpose bounding box that allows a column of elements to be positioned relative to the margin_box.

Arguments:

width

The width of the column in PDF points

Options:

:position

One of :left, :center, :right or an x offset

This method is typically used for flowing a column of text from one page to the next.

span(350, :position => :center) do
  text "Here's some centered text in a 350 point column. " * 100
end


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# File 'lib/prawn/document/span.rb', line 29

def span(width, options = {})
  Prawn.verify_options [:position], options
  original_position = self.y

  # FIXME: Any way to move this upstream?
  left_boundary = case(options[:position] || :left)
                  when :left
                    margin_box.absolute_left
                  when :center
                    margin_box.absolute_left + margin_box.width / 2.0 - width / 2.0
                  when :right
                    margin_box.absolute_right - width
                  when Numeric
                    margin_box.absolute_left + options[:position]
                  else
                    fail ArgumentError, "Invalid option for :position"
                  end

  # we need to bust out of whatever nested bounding boxes we're in.
  canvas do
    bounding_box([left_boundary,
                  margin_box.absolute_top], :width => width) do
      self.y = original_position
      yield
    end
  end
end

#start_new_page(options = {}) ⇒ Object

Creates and advances to a new page in the document.

Page size, margins, and layout can also be set when generating a new page. These values will become the new defaults for page creation

pdf.start_new_page #=> Starts new page keeping current values
pdf.start_new_page(:size => "LEGAL", :layout => :landscape)
pdf.start_new_page(:left_margin => 50, :right_margin => 50)
pdf.start_new_page(:margin => 100)


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# File 'lib/prawn/document.rb', line 242

def start_new_page(options = {})
  if last_page = state.page
    last_page_size    = last_page.size
    last_page_layout  = last_page.layout
    last_page_margins = last_page.margins.dup
  end

  page_options = {
    :size    => options[:size] || last_page_size,
    :layout  => options[:layout] || last_page_layout,
    :margins => last_page_margins
  }
  if last_page
    new_graphic_state = last_page.graphic_state.dup  if last_page.graphic_state

    # erase the color space so that it gets reset on new page for fussy pdf-readers
    new_graphic_state.color_space = {} if new_graphic_state

    page_options.merge!(:graphic_state => new_graphic_state)
  end

  state.page = PDF::Core::Page.new(self, page_options)

  apply_margin_options(options)
  generate_margin_box

  # Reset the bounding box if the new page has different size or layout
  if last_page && (last_page.size != state.page.size ||
                   last_page.layout != state.page.layout)
    @bounding_box = @margin_box
  end

  use_graphic_settings

  unless options[:orphan]
    state.insert_page(state.page, @page_number)
    @page_number += 1

    canvas { image(@background, :scale => @background_scale, :at => bounds.top_left) } if @background
    @y = @bounding_box.absolute_top

    float do
      state.on_page_create_action(self)
    end
  end
end

#width_of(string, options = {}) ⇒ Object

Returns the width of the given string using the given font. If :size is not specified as one of the options, the string is measured using the current font size. You can also pass :kerning as an option to indicate whether kerning should be used when measuring the width (defaults to false).

Note that the string must be encoded properly for the font being used. For AFM fonts, this is WinAnsi. For TTF, make sure the font is encoded as UTF-8. You can use the Font#normalize_encoding method to make sure strings are in an encoding appropriate for the current font. – For the record, this method used to be a method of Font (and still delegates to width computations on Font). However, having the primary interface for calculating string widths exist on Font made it tricky to write extensions for Prawn in which widths are computed differently (e.g., taking formatting tags into account, or the like).

By putting width_of here, on Document itself, extensions may easily override it and redefine the width calculation behavior. ++



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# File 'lib/prawn/font.rb', line 129

def width_of(string, options = {})
  if p = options[:inline_format]
    p = [] unless p.is_a?(Array)

    # Build up an Arranger with the entire string on one line, finalize it,
    # and find its width.
    arranger = Prawn::Text::Formatted::Arranger.new(self, options)
    arranger.consumed = self.text_formatter.format(string, *p)
    arranger.finalize_line

    arranger.line_width
  else
    width_of_string(string, options)
  end
end