Class: HexaPDF::Layout::TextBox

Inherits:
Box
  • Object
show all
Defined in:
lib/hexapdf/layout/text_box.rb

Overview

A TextBox is used for drawing text, either inside a rectangular box or by flowing it around objects of a Frame.

This class uses TextLayouter behind the scenes to do the hard work.

Instance Attribute Summary

Attributes inherited from Box

#height, #style, #width

Instance Method Summary collapse

Methods inherited from Box

#content_height, #content_width, create, #draw, #split_box?

Constructor Details

#initialize(items:, **kwargs) ⇒ TextBox

Creates a new TextBox object with the given inline items (e.g. TextFragment and InlineBox objects).



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# File 'lib/hexapdf/layout/text_box.rb', line 50

def initialize(items:, **kwargs)
  super(**kwargs)
  @tl = TextLayouter.new(style)
  @items = items
  @result = nil
end

Instance Method Details

#empty? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


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# File 'lib/hexapdf/layout/text_box.rb', line 118

def empty?
  super && (!@result || @result.lines.empty?)
end

#fit(available_width, available_height, frame) ⇒ Object

Fits the text box into the Frame.

Depending on the 'position' style property, the text is either fit into the rectangular area given by available_width and available_height, or fit to the outline of the frame starting from the top (when 'position' is set to :flow).

The spacing after the last line can be controlled via the style property last_line_gap.

Also see TextLayouter#style for other style properties taken into account.



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# File 'lib/hexapdf/layout/text_box.rb', line 71

def fit(available_width, available_height, frame)
  return false if (@initial_width > 0 && @initial_width > available_width) ||
    (@initial_height > 0 && @initial_height > available_height)

  @width = @height = 0
  @result = if style.position == :flow
              @tl.fit(@items, frame.width_specification, frame.shape.bbox.height)
            else
              @width = reserved_width
              @height = reserved_height
              width = (@initial_width > 0 ? @initial_width : available_width) - @width
              height = (@initial_height > 0 ? @initial_height : available_height) - @height
              @tl.fit(@items, width, height)
            end
  @width += if @initial_width > 0 || style.align == :center || style.align == :right
              width
            else
              @result.lines.max_by(&:width)&.width || 0
            end
  @height += if @initial_height > 0 || style.valign == :center || style.valign == :bottom
               height
             else
               @result.height
             end
  if style.last_line_gap && @result.lines.last
    @height += style.line_spacing.gap(@result.lines.last, @result.lines.last)
  end

  @result.status == :success
end

#split(available_width, available_height, frame) ⇒ Object

Splits the text box into two boxes if necessary and possible.



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# File 'lib/hexapdf/layout/text_box.rb', line 103

def split(available_width, available_height, frame)
  fit(available_width, available_height, frame) unless @result

  if style.position != :flow && (@width > available_width || @height > available_height)
    [nil, self]
  elsif @result.remaining_items.empty?
    [self]
  elsif @result.lines.empty?
    [nil, self]
  else
    [self, create_box_for_remaining_items]
  end
end

#supports_position_flow? ⇒ Boolean

Returns true as the 'position' style property value :flow is supported.

Returns:

  • (Boolean) 


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# File 'lib/hexapdf/layout/text_box.rb', line 58

def supports_position_flow?
  true
end