class Prawn::Table::Cell
A Cell is a rectangular area of the page into which content is drawn. It has a framework for sizing itself and adding padding and simple styling. There are several standard Cell subclasses that handle things like text, Tables, and (in the future) stamps, images, and arbitrary content.
Cells are a basic building block for table support (see Prawn::Table).
Please subclass me if you want new content types! I'm designed to be very extensible. See the different standard Cell subclasses in lib/prawn/table/cell/*.rb for a template.
Constants
- FPTolerance
A small amount added to the bounding box width to cover over floating- point errors when round-tripping from #content_width to width and back. This does not change cell positioning; it only slightly expands each cell's bounding box width so that rounding error does not prevent a cell from rendering.
Attributes
The background color, if any, for this cell. Specified in HTML RGB format, e.g., “ccffff”. The background is drawn under the whole cell, including any padding.
HTML RGB-format (“ccffff”) border colors: [top, right, bottom, left].
Line style
Width, in PDF points, of the cell's borders: [top, right, bottom, left].
Specifies which borders to enable. Must be an array of zero or more of:
[:left, :right, :top, :bottom]
.
Number of columns this cell spans. Defaults to 1.
Specifies the content for the cell. Must be a “cellable” object. See the “Data” section of the Prawn::Table documentation for details on cellable objects.
Array of SpanDummy cells (if any) that represent the other cells in this span group. They know their own width / height, but do not draw anything.
Manually specify the cell's height.
Amount of dead space (in PDF points) inside the borders but outside the content. Padding defaults to 5pt.
Number of rows this cell spans. Defaults to 1.
Public Class Methods
Given an array of pairs [cell, pt], draws each cell at its corresponding pt, making sure all backgrounds are behind all borders and content.
# File lib/prawn/table/cell.rb, line 410 def self.draw_cells(cells) cells.each do |cell, pt| cell.set_width_constraints cell.draw_background(pt) end cells.each do |cell, pt| cell.draw_borders(pt) cell.draw_bounded_content(pt) end end
Instantiates a Cell based on the given options. The particular class of cell returned depends on the :content argument. See the Prawn::Table documentation under “Data” for allowable content types.
# File lib/prawn/table/cell.rb, line 161 def self.make(pdf, content, options={}) at = options.delete(:at) || [0, pdf.cursor] content = content.to_s if content.nil? || content.kind_of?(Numeric) || content.kind_of?(Date) if content.is_a?(Hash) if content[:image] return Cell::Image.new(pdf, at, content) end options.update(content) content = options[:content] else options[:content] = content end options[:content] = content = "" if content.nil? case content when Prawn::Table::Cell content when String Cell::Text.new(pdf, at, options) when Prawn::Table Cell::Subtable.new(pdf, at, options) when Array subtable = Prawn::Table.new(options[:content], pdf, {}) Cell::Subtable.new(pdf, at, options.merge(:content => subtable)) else raise Errors::UnrecognizedTableContent end end
Sets up a cell on the document pdf
, at the given x/y location
point
, with the given options
. Cell, like Table, follows
the “options set accessors” paradigm (see “Options” under the Table documentation), so any cell accessor
cell.foo = :bar
can be set by providing the option :foo
=> :bar
here.
# File lib/prawn/table/cell.rb, line 207 def initialize(pdf, point, options={}) @pdf = pdf @point = point # Set defaults; these can be changed by options @padding = [5, 5, 5, 5] @borders = [:top, :bottom, :left, :right] @border_widths = [1] * 4 @border_colors = ['000000'] * 4 @border_lines = [:solid] * 4 @colspan = 1 @rowspan = 1 @dummy_cells = [] options.each { |k, v| send("#{k}=", v) } @initializer_run = true end
Public Instance Methods
Min-width of the span divided by the number of columns.
# File lib/prawn/table/cell.rb, line 82 def avg_spanned_min_width min_width.to_f / colspan end
# File lib/prawn/table/cell.rb, line 567 def border_bottom_color @border_colors[2] end
# File lib/prawn/table/cell.rb, line 571 def border_bottom_color=(val) @border_colors[2] = val end
# File lib/prawn/table/cell.rb, line 693 def border_bottom_line @borders.include?(:bottom) ? @border_lines[2] : 0 end
# File lib/prawn/table/cell.rb, line 697 def border_bottom_line=(val) @border_lines[2] = val end
# File lib/prawn/table/cell.rb, line 625 def border_bottom_width @borders.include?(:bottom) ? @border_widths[2] : 0 end
# File lib/prawn/table/cell.rb, line 629 def border_bottom_width=(val) @border_widths[2] = val end
Sets border colors on this cell. The argument can be one of:
-
an integer (sets all colors)
-
a two-element array [vertical, horizontal]
-
a three-element array [top, horizontal, bottom]
-
a four-element array [top, right, bottom, left]
# File lib/prawn/table/cell.rb, line 532 def border_color=(color) @border_colors = case when color.nil? ["000000"] * 4 when String === color # all colors [color, color, color, color] when color.length == 2 # vert, horiz [color[0], color[1], color[0], color[1]] when color.length == 3 # top, horiz, bottom [color[0], color[1], color[2], color[1]] when color.length == 4 # top, right, bottom, left [color[0], color[1], color[2], color[3]] else raise ArgumentError, ":border_color must be a string " + "or an array [v,h] or [t,r,b,l]" end end
# File lib/prawn/table/cell.rb, line 575 def border_left_color @border_colors[3] end
# File lib/prawn/table/cell.rb, line 579 def border_left_color=(val) @border_colors[3] = val end
# File lib/prawn/table/cell.rb, line 701 def border_left_line @borders.include?(:left) ? @border_lines[3] : 0 end
# File lib/prawn/table/cell.rb, line 705 def border_left_line=(val) @border_lines[3] = val end
# File lib/prawn/table/cell.rb, line 633 def border_left_width @borders.include?(:left) ? @border_widths[3] : 0 end
# File lib/prawn/table/cell.rb, line 637 def border_left_width=(val) @border_widths[3] = val end
Sets border line style on this cell. The argument can be one of:
Possible values are: :solid, :dashed, :dotted
-
one value (sets all lines)
-
a two-element array [vertical, horizontal]
-
a three-element array [top, horizontal, bottom]
-
a four-element array [top, right, bottom, left]
# File lib/prawn/table/cell.rb, line 658 def border_line=(line) @border_lines = case when line.nil? [:solid] * 4 when line.length == 1 # all lines [line[0]] * 4 when line.length == 2 [line[0], line[1], line[0], line[1]] when line.length == 3 [line[0], line[1], line[2], line[1]] when line.length == 4 [line[0], line[1], line[2], line[3]] else raise ArgumentError, "border_line must be one of :solid, :dashed, " ":dotted or an array [v,h] or [t,r,b,l]" end end
# File lib/prawn/table/cell.rb, line 559 def border_right_color @border_colors[1] end
# File lib/prawn/table/cell.rb, line 563 def border_right_color=(val) @border_colors[1] = val end
# File lib/prawn/table/cell.rb, line 685 def border_right_line @borders.include?(:right) ? @border_lines[1] : 0 end
# File lib/prawn/table/cell.rb, line 689 def border_right_line=(val) @border_lines[1] = val end
# File lib/prawn/table/cell.rb, line 617 def border_right_width @borders.include?(:right) ? @border_widths[1] : 0 end
# File lib/prawn/table/cell.rb, line 621 def border_right_width=(val) @border_widths[1] = val end
# File lib/prawn/table/cell.rb, line 551 def border_top_color @border_colors[0] end
# File lib/prawn/table/cell.rb, line 555 def border_top_color=(val) @border_colors[0] = val end
# File lib/prawn/table/cell.rb, line 677 def border_top_line @borders.include?(:top) ? @border_lines[0] : 0 end
# File lib/prawn/table/cell.rb, line 681 def border_top_line=(val) @border_lines[0] = val end
# File lib/prawn/table/cell.rb, line 609 def border_top_width @borders.include?(:top) ? @border_widths[0] : 0 end
# File lib/prawn/table/cell.rb, line 613 def border_top_width=(val) @border_widths[0] = val end
Sets border widths on this cell. The argument can be one of:
-
an integer (sets all widths)
-
a two-element array [vertical, horizontal]
-
a three-element array [top, horizontal, bottom]
-
a four-element array [top, right, bottom, left]
# File lib/prawn/table/cell.rb, line 590 def border_width=(width) @border_widths = case when width.nil? ["000000"] * 4 when Numeric === width # all widths [width, width, width, width] when width.length == 2 # vert, horiz [width[0], width[1], width[0], width[1]] when width.length == 3 # top, horiz, bottom [width[0], width[1], width[2], width[1]] when width.length == 4 # top, right, bottom, left [width[0], width[1], width[2], width[3]] else raise ArgumentError, ":border_width must be a string " + "or an array [v,h] or [t,r,b,l]" end end
Indicates the number of columns that this cell is to span. Defaults to 1.
This must be provided as part of the table data, like so:
pdf.table([["foo", {:content => "bar", :colspan => 2}]])
Setting colspan from the initializer block is invalid because layout has already run. For example, this will NOT work:
pdf.table([["foo", "bar"]]) { cells[0, 1].colspan = 2 }
# File lib/prawn/table/cell.rb, line 364 def colspan=(span) if defined?(@initializer_run) && @initializer_run raise Prawn::Errors::InvalidTableSpan, "colspan must be provided in the table's structure, never in the " + "initialization block. See Prawn's documentation for details." end @colspan = span end
Returns the height of the bare content in the cell, excluding padding.
# File lib/prawn/table/cell.rb, line 330 def content_height if defined?(@height) && @height # manually set return @height - padding_top - padding_bottom end natural_content_height end
Returns the width of the bare content in the cell, excluding padding.
# File lib/prawn/table/cell.rb, line 280 def content_width if defined?(@width) && @width # manually set return @width - padding_left - padding_right end natural_content_width end
Draws the cell onto the document. Pass in a point [x,y] to override the location at which the cell is drawn.
If drawing a group of cells at known positions, look into ::draw_cells, which ensures that the backgrounds, borders, and content are all drawn in correct order so as not to overlap.
# File lib/prawn/table/cell.rb, line 402 def draw(pt=[x, y]) Prawn::Table::Cell.draw_cells([[self, pt]]) end
Draws the cell's background color.
# File lib/prawn/table/cell.rb, line 711 def draw_background(pt) return unless background_color @pdf.mask(:fill_color) do @pdf.fill_color background_color @pdf.fill_rectangle pt, width, height end end
Draws borders around the cell. Borders are centered on the bounds of the cell outside of any padding, so the caller is responsible for setting appropriate padding to ensure the border does not overlap with cell content.
# File lib/prawn/table/cell.rb, line 725 def draw_borders(pt) x, y = pt @pdf.mask(:line_width, :stroke_color) do @borders.each do |border| idx = {:top => 0, :right => 1, :bottom => 2, :left => 3}[border] border_color = @border_colors[idx] border_width = @border_widths[idx] border_line = @border_lines[idx] next if border_width <= 0 # Left and right borders are drawn one-half border beyond the center # of the corner, so that the corners end up square. from, to = case border when :top [[x, y], [x+width, y]] when :bottom [[x, y-height], [x+width, y-height]] when :left [[x, y + (border_top_width / 2.0)], [x, y - height - (border_bottom_width / 2.0)]] when :right [[x+width, y + (border_top_width / 2.0)], [x+width, y - height - (border_bottom_width / 2.0)]] end case border_line when :dashed @pdf.dash border_width * 4 when :dotted @pdf.dash border_width, :space => border_width * 2 when :solid # normal line style else raise ArgumentError, "border_line must be :solid, :dotted or" + " :dashed" end @pdf.line_width = border_width @pdf.stroke_color = border_color @pdf.stroke_line(from, to) @pdf.undash end end end
Draws the cell's content at the point provided.
# File lib/prawn/table/cell.rb, line 424 def draw_bounded_content(pt) @pdf.float do @pdf.bounding_box([pt[0] + padding_left, pt[1] - padding_top], :width => spanned_content_width + FPTolerance, :height => spanned_content_height + FPTolerance) do draw_content end end end
Draws cell content within the cell's bounding box. Must be implemented in subclasses.
# File lib/prawn/table/cell.rb, line 775 def draw_content raise NotImplementedError, "subclasses must implement draw_content" end
Returns the cell's height in points, inclusive of padding. If the cell is the master cell of a rowspan, returns the width of the entire span group.
# File lib/prawn/table/cell.rb, line 315 def height return height_ignoring_span if @colspan == 1 && @rowspan == 1 # We're in a span group; get the maximum height per row (including the # master cell) and sum each row. row_heights = Hash.new(0) dummy_cells.each do |cell| row_heights[cell.row] = [row_heights[cell.row], cell.height].max end row_heights[row] = [row_heights[row], height_ignoring_span].max row_heights.values.inject(0, &:+) end
Returns the cell's height in points, inclusive of padding, in its first row only.
# File lib/prawn/table/cell.rb, line 305 def height_ignoring_span # We can't ||= here because the FP error accumulates on the round-trip # from #content_height. defined?(@height) && @height || (content_height + padding_top + padding_bottom) end
Maximum width of the entire span group this cell controls.
# File lib/prawn/table/cell.rb, line 96 def max_width return max_width_ignoring_span if @colspan == 1 # Sum the smallest max-width from each column in the group, including # myself. max_widths = Hash.new(0) dummy_cells.each do |cell| max_widths[cell.column] = [max_widths[cell.column], cell.max_width].min end max_widths[column] = [max_widths[column], max_width_ignoring_span].min max_widths.values.inject(0, &:+) end
If provided, the maximum width that this cell can be drawn in, within its column.
# File lib/prawn/table/cell.rb, line 89 def max_width_ignoring_span set_width_constraints @max_width end
Minimum width of the entire span group this cell controls.
# File lib/prawn/table/cell.rb, line 67 def min_width return min_width_ignoring_span if @colspan == 1 # Sum up the largest min-width from each column, including myself. min_widths = Hash.new(0) dummy_cells.each do |cell| min_widths[cell.column] = [min_widths[cell.column], cell.min_width].max end min_widths[column] = [min_widths[column], min_width_ignoring_span].max min_widths.values.inject(0, &:+) end
If provided, the minimum width that this cell in its column will permit.
# File lib/prawn/table/cell.rb, line 60 def min_width_ignoring_span set_width_constraints @min_width end
Returns the height this cell would naturally take on, absent constraints. Must be implemented in subclasses.
# File lib/prawn/table/cell.rb, line 347 def natural_content_height raise NotImplementedError, "subclasses must implement natural_content_height" end
Returns the width this cell would naturally take on, absent other constraints. Must be implemented in subclasses.
# File lib/prawn/table/cell.rb, line 297 def natural_content_width raise NotImplementedError, "subclasses must implement natural_content_width" end
Sets padding on this cell. The argument can be one of:
-
an integer (sets all padding)
-
a two-element array [vertical, horizontal]
-
a three-element array [top, horizontal, bottom]
-
a four-element array [top, right, bottom, left]
# File lib/prawn/table/cell.rb, line 475 def padding=(pad) @padding = case when pad.nil? [0, 0, 0, 0] when Numeric === pad # all padding [pad, pad, pad, pad] when pad.length == 2 # vert, horiz [pad[0], pad[1], pad[0], pad[1]] when pad.length == 3 # top, horiz, bottom [pad[0], pad[1], pad[2], pad[1]] when pad.length == 4 # top, right, bottom, left [pad[0], pad[1], pad[2], pad[3]] else raise ArgumentError, ":padding must be a number or an array [v,h] " + "or [t,r,b,l]" end end
# File lib/prawn/table/cell.rb, line 509 def padding_bottom @padding[2] end
# File lib/prawn/table/cell.rb, line 513 def padding_bottom=(val) @padding[2] = val end
# File lib/prawn/table/cell.rb, line 517 def padding_left @padding[3] end
# File lib/prawn/table/cell.rb, line 521 def padding_left=(val) @padding[3] = val end
# File lib/prawn/table/cell.rb, line 501 def padding_right @padding[1] end
# File lib/prawn/table/cell.rb, line 505 def padding_right=(val) @padding[1] = val end
# File lib/prawn/table/cell.rb, line 493 def padding_top @padding[0] end
# File lib/prawn/table/cell.rb, line 497 def padding_top=(val) @padding[0] = val end
# File lib/prawn/table/cell.rb, line 446 def relative_x # 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 end
# File lib/prawn/table/cell.rb, line 464 def relative_y(offset = 0) y + offset - @pdf.bounds.absolute_bottom end
Indicates the number of rows that this cell is to span. Defaults to 1.
This must be provided as part of the table data, like so:
pdf.table([["foo", {:content => "bar", :rowspan => 2}], ["baz"]])
Setting rowspan from the initializer block is invalid because layout has already run. For example, this will NOT work:
pdf.table([["foo", "bar"], ["baz"]]) { cells[0, 1].rowspan = 2 }
# File lib/prawn/table/cell.rb, line 385 def rowspan=(span) if defined?(@initializer_run) && @initializer_run raise Prawn::Errors::InvalidTableSpan, "rowspan must be provided in the table's structure, never in the " + "initialization block. See Prawn's documentation for details." end @rowspan = span end
Sets the cell's minimum and maximum width. Deferred until requested because padding and size can change.
# File lib/prawn/table/cell.rb, line 644 def set_width_constraints @min_width ||= padding_left + padding_right @max_width ||= @pdf.bounds.width end
Height of the entire span group.
# File lib/prawn/table/cell.rb, line 340 def spanned_content_height height - padding_top - padding_bottom end
Width of the entire span group.
# File lib/prawn/table/cell.rb, line 290 def spanned_content_width width - padding_left - padding_right end
Supports setting multiple properties at once.
cell.style(:padding => 0, :border_width => 2)
is the same as:
cell.padding = 0 cell.border_width = 2
# File lib/prawn/table/cell.rb, line 235 def style(options={}, &block) options.each do |k, v| send("#{k}=", v) if respond_to?("#{k}=") end # The block form supports running a single block for multiple cells, as # in Cells#style. block.call(self) if block end
Returns the cell's width in points, inclusive of padding. If the cell is the master cell of a colspan, returns the width of the entire span group.
# File lib/prawn/table/cell.rb, line 258 def width return width_ignoring_span if @colspan == 1 && @rowspan == 1 # We're in a span group; get the maximum width per column (including # the master cell) and sum each column. column_widths = Hash.new(0) dummy_cells.each do |cell| column_widths[cell.column] = [column_widths[cell.column], cell.width].max end column_widths[column] = [column_widths[column], width_ignoring_span].max column_widths.values.inject(0, &:+) end
Manually sets the cell's width, inclusive of padding.
# File lib/prawn/table/cell.rb, line 274 def width=(w) @width = @min_width = @max_width = w end
Returns the width of the cell in its first column alone, ignoring any colspans.
# File lib/prawn/table/cell.rb, line 248 def width_ignoring_span # We can't ||= here because the FP error accumulates on the round-trip # from #content_width. defined?(@width) && @width || (content_width + padding_left + padding_right) end
x-position of the cell within the parent bounds.
# File lib/prawn/table/cell.rb, line 436 def x @point[0] end
Set the x-position of the cell within the parent bounds.
# File lib/prawn/table/cell.rb, line 442 def x=(val) @point[0] = val end
y-position of the cell within the parent bounds.
# File lib/prawn/table/cell.rb, line 454 def y @point[1] end
Set the y-position of the cell within the parent bounds.
# File lib/prawn/table/cell.rb, line 460 def y=(val) @point[1] = val end