### Home Classes Methods

### In Files

- lib/prawn/table.rb
- lib/prawn/table/cell.rb
- lib/prawn/table/cells.rb
- lib/prawn/table/cell/span_dummy.rb
- lib/prawn/table/cell/subtable.rb
- lib/prawn/table/cell/in_table.rb
- lib/prawn/table/cell/text.rb
- lib/prawn/table/cell/image.rb
- lib/prawn/table/column_width_calculator.rb

### Parent

Object

### Namespace

- CLASS Prawn::Table::Cell
- CLASS Prawn::Table::Cells
- CLASS Prawn::Table::ColumnWidthCalculator

### Methods

- ::new
- #add_header
- #assert_proper_table_data
- #before_rendering_page
- #cell_style=
- #column
- #column_widths
- #column_widths=
- #columns
- #draw
- #height
- #make_cells
- #natural_column_widths
- #natural_width
- #position_cells
- #row
- #row_heights
- #rows
- #set_column_widths
- #set_row_heights
- #style
- #width
- #with_position

### Class/Module Index

Quicksearch

- Prawn
- Prawn::Configurable
- Prawn::Document
- Prawn::Document::BoundingBox
- Prawn::Document::ColumnBox
- Prawn::Document::GraphicsState
- Prawn::Document::Grid
- Prawn::Document::GridBox
- Prawn::Document::Internals
- Prawn::Document::Security
- Prawn::Document::Snapshot
- Prawn::Encoding
- Prawn::Errors
- Prawn::Font
- Prawn::Font::AFM
- Prawn::Font::DFont
- Prawn::Font::TTF
- Prawn::FontMetricCache
- Prawn::Graphics
- Prawn::Graphics::CapStyle
- Prawn::Graphics::Color
- Prawn::Graphics::Dash
- Prawn::Graphics::JoinStyle
- Prawn::Graphics::Patterns
- Prawn::Graphics::Transformation
- Prawn::Graphics::Transparency
- Prawn::ImageHandler
- Prawn::Images
- Prawn::Images::Image
- Prawn::Images::JPG
- Prawn::Images::PNG
- Prawn::Measurements
- Prawn::SoftMask
- Prawn::Stamp
- Prawn::SynchronizedCache
- Prawn::Table
- Prawn::Table::Cell
- Prawn::Table::Cell::Image
- Prawn::Table::Cell::InTable
- Prawn::Table::Cell::SpanDummy
- Prawn::Table::Cell::Subtable
- Prawn::Table::Cell::Text
- Prawn::Table::Cells
- Prawn::Table::ColumnWidthCalculator
- Prawn::Text
- Prawn::Text::Box
- Prawn::Text::Formatted
- Prawn::Text::Formatted::Box
- Prawn::Text::Formatted::Fragment
- Prawn::Text::Formatted::Parser
- Prawn::ThreadLocalCache
- PDF
- PDF::Core
- PDF::Core::Reference
- PDF::Core::Stream
- Arcfour
- Numeric

No matching classes.

# Prawn::Table

Next-generation table drawing for Prawn.

# Data

Data, for a Prawn table, is a two-dimensional array of objects that can be converted to cells ("cellable" objects). Cellable objects can be:

String | Produces a text cell. This is the most common usage.
Prawn::Table::Cell | If you have already built a Cell or have a custom subclass of Cell you want to use in a table, you can pass through Cell objects.
Prawn::Table | Creates a subtable (a table within a cell). You can use Prawn::Document#make_table to create a table for use as a subtable without immediately drawing it. See examples/table/bill.rb for a somewhat complex use of subtables.
Array | Creates a simple subtable. Create a Table object using make_table (see above) if you need more control over the subtable's styling.

# Options

Prawn/Layout provides many options to control style and layout of your table. These options are implemented with a uniform interface: the `:foo` option always sets the `foo=` accessor. See the accessor and method documentation for full details on the options you can pass. Some highlights:

`cell_style` | A hash of style options to style all cells. See the documentation on Prawn::Table::Cell for all cell style options.
`header` | If set to `true`, the first row will be repeated on every page. If set to an Integer, the first `x` rows will be repeated on every page. Row numbering (for styling and other row-specific options) always indexes based on your data array. Whether or not you have a header, row(n) always refers to the nth element (starting from 0) of the `data` array.
`column_widths` | Sets widths for individual columns. Manually setting widths can give better results than letting Prawn guess at them, as Prawn's algorithm for defaulting widths is currently pretty boneheaded. If you experience problems like weird column widths or CannotFit errors, try manually setting widths on more columns.
`position` | Either :left (the default), :center, :right, or a number. Specifies the horizontal position of the table within its bounding box. If a number is provided, it specifies the distance in points from the left edge.

# Initializer Block

If a block is passed to methods that initialize a table (Prawn::Table.new, Prawn::Document#table, Prawn::Document#make_table), it will be called after cell setup but before layout. This is a very flexible way to specify styling and layout constraints. This code sets up a table where the second through the fourth rows (1-3, indexed from 0) are each one inch (72 pt) wide:

    pdf.table(data) do |table|
      table.rows(1..3).width = 72
    end

As with Prawn::Document#initialize, if the block has no arguments, it will be evaluated in the context of the object itself. The above code could be rewritten as:

    pdf.table(data) do
      rows(1..3).width = 72
    end

### Attributes

cells[R]

Returns a Prawn::Table::Cells object representing all of the cells in this table.

column_length[R]

Number of columns in the table.

header[W]

If `true`, designates the first row as a header row to be repeated on every page. If an integer, designates the number of rows to be treated as a header Does not change row numbering -- row numbers always index into the data array provided, with no modification.

position[W]

Position (:left, :right, :center, or a number indicating distance in points from the left edge) of the table within its parent bounds.

row_colors[W]

Accepts an Array of alternating row colors to stripe the table.

row_length[R]

Number of rows in the table.

width[W]

Manually set the width of the table.

### Public Class Methods

new(data, document, options={}, &block) click to toggle source

Set up a table on the given document. Arguments:

`data` | A two-dimensional array of cell-like objects. See the "Data" section above for the types of objects that can be put in a table.
`document` | The Prawn::Document instance on which to draw the table.
`options` | A hash of attributes and values for the table. See the "Options" block above for details on available options.

    # File lib/prawn/table.rb, line 128
    def initialize(data, document, options={}, &block)
      @pdf = document
      @cells = make_cells(data)
      @header = false
      @epsilon = 1e-9
      options.each { |k, v| send("#{k}=", v) }

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

      set_column_widths
      set_row_heights
      position_cells
    end

### Public Instance Methods

before_rendering_page(&block) click to toggle source

Specify a callback to be called before each page of cells is rendered. The block is passed a Cells object containing all cells to be rendered on that page. You can change styling of the cells in this block, but keep in mind that the cells have already been positioned and sized.

    # File lib/prawn/table.rb, line 171
    def before_rendering_page(&block)
      @before_rendering_page = block
    end

cell_style=(style_hash) click to toggle source

Sets styles for all cells.

    pdf.table(data, :cell_style => { :borders => [:left, :right] })

    # File lib/prawn/table.rb, line 226
    def cell_style=(style_hash)
      cells.style(style_hash)
    end

column(col_spec) click to toggle source
Alias for: columns
column_widths() click to toggle source

Calculate and return the constrained column widths, taking into account each cell's min_width, max_width, and any user-specified constraints on the table or column size.

Because the natural widths can be silly, this does not always work so well at guessing a good size for columns that have vastly different content. If you see weird problems like CannotFit errors or shockingly bad column sizes, you should specify more column widths manually.

    # File lib/prawn/table.rb, line 396
    def column_widths
      @column_widths ||= begin
        if width - cells.min_width < -epsilon
          raise Errors::CannotFit,
            "Table's width was set too small to contain its contents " +
            "(min width #{cells.min_width}, requested #{width})"
        end

        if width - cells.max_width > epsilon
          raise Errors::CannotFit,
            "Table's width was set larger than its contents' maximum width " +
            "(max width #{cells.max_width}, requested #{width})"
        end

        if width - natural_width < -epsilon
          # Shrink the table to fit the requested width.
          f = (width - cells.min_width).to_f / (natural_width - cells.min_width)

          (0...column_length).map do |c|
            min, nat = column(c).min_width, natural_column_widths[c]
            (f * (nat - min)) + min
          end
        elsif width - natural_width > epsilon
          # Expand the table to fit the requested width.
          f = (width - cells.width).to_f / (cells.max_width - cells.width)

          (0...column_length).map do |c|
            nat, max = natural_column_widths[c], column(c).max_width
            (f * (max - nat)) + nat
          end
        else
          natural_column_widths
        end
      end
    end

column_widths=(widths) click to toggle source

Sets column widths for the table. The argument can be one of the following types:

`Array` | `[w0, w1, w2, ...]` (specify a width for each column)
`Hash` | `{0 => w0, 1 => w1, ...}` (keys are column names, values are widths)
`Numeric` | `72` (sets width for all columns)

    # File lib/prawn/table.rb, line 192
    def column_widths=(widths)
      case widths
      when Array
        widths.each_with_index { |w, i| column(i).width = w }
      when Hash
        widths.each { |i, w| column(i).width = w }
      when Numeric
        cells.width = widths
      else
        raise ArgumentError, "cannot interpret column widths"
      end
    end

columns(col_spec) click to toggle source

Selects the given columns (0-based) for styling. Returns a Cells object -- see the documentation on Cells for things you can do with cells.

    # File lib/prawn/table/cells.rb, line 21
    def columns(col_spec)
      cells.columns(col_spec)
    end

Also aliased as: column
draw() click to toggle source

Draws the table onto the document at the document's current y-position.

    # File lib/prawn/table.rb, line 251
    def draw
      with_position do
        # The cell y-positions are based on an infinitely long canvas. The offset
        # keeps track of how much we have to add to the original, theoretical
        # y-position to get to the actual position on the current page.
        offset = @pdf.y

        # Reference bounds are the non-stretchy bounds used to decide when to
        # flow to a new column / page.
        ref_bounds = @pdf.reference_bounds

        last_y = @pdf.y

        # Determine whether we're at the top of the current bounds (margin box or
        # bounding box). If we're at the top, we couldn't gain any more room by
        # breaking to the next page -- this means, in particular, that if the
        # first row is taller than the margin box, we will only move to the next
        # page if we're below the top. Some floating-point tolerance is added to
        # the calculation.
        #
        # Note that we use the actual bounds, not the reference bounds. This is
        # because even if we are in a stretchy bounding box, flowing to the next
        # page will not buy us any space if we are at the top.
        if @pdf.y > @pdf.bounds.height + @pdf.bounds.absolute_bottom - 0.001
          # we're at the top of our bounds
          started_new_page_at_row = 0
        else
          started_new_page_at_row = -1

          # If there isn't enough room left on the page to fit the first data row
          # (excluding the header), start the table on the next page.
          needed_height = row(0).height
          if @header
            if @header.is_a? Integer
              needed_height += row(1..@header).height
            else
              needed_height += row(1).height
            end
          end
          if needed_height > @pdf.y - ref_bounds.absolute_bottom
            @pdf.bounds.move_past_bottom
            offset = @pdf.y
            started_new_page_at_row = 0
          end
        end

        # Duplicate each cell of the header row into @header_row so it can be
        # modified in before_rendering_page callbacks.
        if @header
          @header_row = Cells.new
          if @header.is_a? Integer
            @header.times do |r|
              row(r).each { |cell| @header_row[cell.row, cell.column] = cell.dup }
            end
          else
            row(0).each { |cell| @header_row[cell.row, cell.column] = cell.dup }
          end
        end

        # Track cells to be drawn on this page. They will all be drawn when this
        # page is finished.
        cells_this_page = []

        @cells.each do |cell|
          if cell.height > (cell.y + offset) - ref_bounds.absolute_bottom &&
             cell.row > started_new_page_at_row
            # Ink all cells on the current page
            if defined?(@before_rendering_page) && @before_rendering_page
              c = Cells.new(cells_this_page.map { |ci, _| ci })
              @before_rendering_page.call(c)
            end
            Cell.draw_cells(cells_this_page)
            cells_this_page = []

            # start a new page or column
            @pdf.bounds.move_past_bottom
            x_offset = @pdf.bounds.left_side - @pdf.bounds.absolute_left
            if cell.row > 0 && @header
              if @header.is_a? Integer
                header_height = 0
                y_coord = @pdf.cursor
                @header.times do |h|
                  additional_header_height = add_header(cells_this_page, x_offset, y_coord-header_height, cell.row-1, h)
                  header_height += additional_header_height
                end
              else
                header_height = add_header(cells_this_page, x_offset, @pdf.cursor, cell.row-1)
              end
            else
              header_height = 0
            end
            offset = @pdf.y - cell.y - header_height
            started_new_page_at_row = cell.row
          end

          # Don't modify cell.x / cell.y here, as we want to reuse the original
          # values when re-inking the table. #draw should be able to be called
          # multiple times.
          x, y = cell.x, cell.y
          y += offset

          # Translate coordinates to the bounds we are in, since drawing is
          # relative to the cursor, not ref_bounds.
          x += @pdf.bounds.left_side - @pdf.bounds.absolute_left
          y -= @pdf.bounds.absolute_bottom

          # Set background color, if any.
          if defined?(@row_colors) && @row_colors && (!@header || cell.row > 0)
            # Ensure coloring restarts on every page (to make sure the header
            # and first row of a page are not colored the same way).
            if @header.is_a? Integer
              rows = @header
            elsif @header
              rows = 1
            else
              rows = 0
            end
            index = cell.row - [started_new_page_at_row, rows].max

            cell.background_color ||= @row_colors[index % @row_colors.length]
          end

          cells_this_page << [cell, [x, y]]
          last_y = y
        end
        # Draw the last page of cells
        if defined?(@before_rendering_page) && @before_rendering_page
          c = Cells.new(cells_this_page.map { |ci, _| ci })
          @before_rendering_page.call(c)
        end
        Cell.draw_cells(cells_this_page)

        @pdf.move_cursor_to(last_y - @cells.last.height)
      end
    end

height() click to toggle source

Returns the height of the table in PDF points.

    # File lib/prawn/table.rb, line 207
    def height
      cells.height
    end

row(row_spec) click to toggle source
Alias for: rows
row_heights() click to toggle source

Returns an array with the height of each row.

    # File lib/prawn/table.rb, line 434
    def row_heights
      @natural_row_heights ||=
        begin
          heights_by_row = Hash.new(0)
          cells.each do |cell|
            next if cell.is_a?(Cell::SpanDummy)

            # Split the height of row-spanned cells evenly by rows
            height_per_row = cell.height.to_f / cell.rowspan
            cell.rowspan.times do |i|
              heights_by_row[cell.row + i] =
                [heights_by_row[cell.row + i], height_per_row].max
            end
          end
          heights_by_row.sort_by { |row, _| row }.map { |_, h| h }
        end
    end

rows(row_spec) click to toggle source

Selects the given rows (0-based) for styling. Returns a Cells object -- see the documentation on Cells for things you can do with cells.

    # File lib/prawn/table/cells.rb, line 13
    def rows(row_spec)
      cells.rows(row_spec)
    end

Also aliased as: row
style(stylable, style_hash={}, &block) click to toggle source

Allows generic stylable content. This is an alternate syntax that some prefer to the attribute-based syntax. This code using style:

    pdf.table(data) do
      style(row(0), :background_color => 'ff00ff')
      style(column(0)) { |c| c.border_width += 1 }
    end

is equivalent to:

    pdf.table(data) do
      row(0).style :background_color => 'ff00ff'
      column(0).style { |c| c.border_width += 1 }
    end

    # File lib/prawn/table.rb, line 245
    def style(stylable, style_hash={}, &block)
      stylable.style(style_hash, &block)
    end

width() click to toggle source

Returns the width of the table in PDF points.

    # File lib/prawn/table.rb, line 177
    def width
      @width ||= [natural_width, @pdf.bounds.width].min
    end

### Protected Instance Methods

add_header(page_of_cells, x_offset, y, row, row_of_header=nil) click to toggle source

Add the header row(s) to the given array of cells at the given y-position. Number the row with the given `row` index, so that the header appears (in any Cells built for this page) immediately prior to the first data row on this page.

Return the height of the header.

    # File lib/prawn/table.rb, line 524
    def add_header(page_of_cells, x_offset, y, row, row_of_header=nil)
      rows_to_operate_on = @header_row
      rows_to_operate_on = @header_row.rows(row_of_header) if row_of_header
      rows_to_operate_on.each do |cell|
        cell.row = row
        cell.dummy_cells.each {|c| c.row = row }
        page_of_cells << [cell, [cell.x + x_offset, y]]
      end
      rows_to_operate_on.height
    end

assert_proper_table_data(data) click to toggle source

Raises an error if the data provided cannot be converted into a valid table.

    # File lib/prawn/table.rb, line 538
    def assert_proper_table_data(data)
      if data.nil? || data.empty?
        raise Prawn::Errors::EmptyTable,
          "data must be a non-empty, non-nil, two dimensional array " +
          "of cell-convertible objects"
      end

      unless data.all? { |e| Array === e }
        raise Prawn::Errors::InvalidTableData,
          "data must be a two dimensional array of cellable objects"
      end
    end

make_cells(data) click to toggle source

Converts the array of cellable objects given into instances of Prawn::Table::Cell, and sets up their in-table properties so that they know their own position in the table.

    # File lib/prawn/table.rb, line 458
    def make_cells(data)
      assert_proper_table_data(data)

      cells = Cells.new

      row_number = 0
      data.each do |row_cells|
        column_number = 0
        row_cells.each do |cell_data|
          # If we landed on a spanned cell (from a rowspan above), continue
          # until we find an empty spot.
          column_number += 1 until cells[row_number, column_number].nil?

          # Build the cell and store it in the Cells collection.
          cell = Cell.make(@pdf, cell_data)
          cells[row_number, column_number] = cell

          # Add dummy cells for the rest of the cells in the span group. This
          # allows Prawn to keep track of the horizontal and vertical space
          # occupied in each column and row spanned by this cell, while still
          # leaving the master (top left) cell in the group responsible for
          # drawing. Dummy cells do not put ink on the page.
          cell.rowspan.times do |i|
            cell.colspan.times do |j|
              next if i == 0 && j == 0

              # It is an error to specify spans that overlap; catch this here
              if cells[row_number + i, column_number + j]
                raise Prawn::Errors::InvalidTableSpan,
                  "Spans overlap at row #{row_number + i}, " +
                  "column #{column_number + j}."
              end

              dummy = Cell::SpanDummy.new(@pdf, cell)
              cells[row_number + i, column_number + j] = dummy
              cell.dummy_cells << dummy
            end
          end

          column_number += cell.colspan
        end

        row_number += 1
      end

      # Calculate the number of rows and columns in the table, taking into
      # account that some cells may span past the end of the physical cells we
      # have.
      @row_length = cells.map do |cell|
        cell.row + cell.rowspan
      end.max

      @column_length = cells.map do |cell|
        cell.column + cell.colspan
      end.max

      cells
    end

natural_column_widths() click to toggle source

Returns an array of each column's natural (unconstrained) width.

    # File lib/prawn/table.rb, line 553
    def natural_column_widths
      @natural_column_widths ||= ColumnWidthCalculator.new(cells).natural_widths
    end

natural_width() click to toggle source

Returns the "natural" (unconstrained) width of the table. This may be extremely silly; for example, the unconstrained width of a paragraph of text is the width it would assume if it were not wrapped at all. Could be a mile long.

    # File lib/prawn/table.rb, line 562
    def natural_width
      @natural_width ||= natural_column_widths.inject(0, &:+)
    end

position_cells() click to toggle source

Set each cell's position based on the widths and heights of cells preceding it.

    # File lib/prawn/table.rb, line 587
    def position_cells
      # Calculate x- and y-positions as running sums of widths / heights.
      x_positions = column_widths.inject([0]) { |ary, x|
        ary << (ary.last + x); ary }[0..-2]
      x_positions.each_with_index { |x, i| column(i).x = x }

      # y-positions assume an infinitely long canvas starting at zero -- this
      # is corrected for in Table#draw, and page breaks are properly inserted.
      y_positions = row_heights.inject([0]) { |ary, y|
        ary << (ary.last - y); ary}[0..-2]
      y_positions.each_with_index { |y, i| row(i).y = y }
    end

set_column_widths() click to toggle source

Assigns the calculated column widths to each cell. This ensures that each cell in a column is the same width. After this method is called, subsequent calls to column_widths and width should return the finalized values that will be used to ink the table.

    # File lib/prawn/table.rb, line 571
    def set_column_widths
      column_widths.each_with_index do |w, col_num|
        column(col_num).width = w
      end
    end

set_row_heights() click to toggle source

Assigns the row heights to each cell. This ensures that every cell in a row is the same height.

    # File lib/prawn/table.rb, line 580
    def set_row_heights
      row_heights.each_with_index { |h, row_num| row(row_num).height = h }
    end

with_position() click to toggle source

Sets up a bounding box to position the table according to the specified :position option, and yields.

    # File lib/prawn/table.rb, line 603
    def with_position
      x = case defined?(@position) && @position || :left
          when :left   then return yield
          when :center then (@pdf.bounds.width - width) / 2.0
          when :right  then  @pdf.bounds.width - width
          when Numeric then  @position
          else raise ArgumentError, "unknown position #{@position.inspect}"
          end
      dy = @pdf.bounds.absolute_top - @pdf.y
      final_y = nil

      @pdf.bounding_box([x, @pdf.bounds.top], :width => width) do
        @pdf.move_down dy
        yield
        final_y = @pdf.y
      end

      @pdf.y = final_y
    end

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