Class: HexaPDF::Type::Form

Inherits:
Stream show all
Defined in:
lib/hexapdf/type/form.rb

Overview

Represents a form XObject of a PDF document.

See: PDF1.7 s8.10

Constant Summary

Constants included from DictionaryFields

DictionaryFields::Boolean, DictionaryFields::PDFByteString, DictionaryFields::PDFDate

Constants inherited from Object

Object::NOT_DUPLICATABLE_CLASSES

Instance Attribute Summary collapse

Attributes inherited from Object

#data, #document, #must_be_indirect

Instance Method Summary collapse

Methods inherited from Stream

#must_be_indirect?, #raw_stream, #set_filter, #stream, #stream=, #stream_decoder, #stream_encoder, #stream_source

Methods inherited from Dictionary

#[], #[]=, define_field, define_type, #delete, #each, each_field, #empty?, field, #key?, #to_h, type, #type

Methods inherited from Object

#<=>, #==, deep_copy, #deep_copy, #document?, #eql?, #gen, #gen=, #hash, #indirect?, #initialize, #inspect, #must_be_indirect?, #null?, #oid, #oid=, #type, #validate, #value, #value=

Constructor Details

This class inherits a constructor from HexaPDF::Object

Instance Attribute Details

#source_pathObject

Returns the path to the PDF file that was used when creating the form object.

This value is only set when the form object was created by using the image loading facility (i.e. when treating a single page PDF file as image) and not when the form object was created in any other way (i.e. manually created or already part of a loaded PDF file).



68
69
70
# File 'lib/hexapdf/type/form.rb', line 68

def source_path
  @source_path
end

Instance Method Details

#boxObject

Returns the rectangle defining the bounding box of the form.



71
72
73
# File 'lib/hexapdf/type/form.rb', line 71

def box
  self[:BBox]
end

#canvasObject

Returns the canvas for the form XObject.

The canvas object is cached once it is created so that its graphics state is correctly retained without the need for parsing its contents.

Note that a canvas can only be retrieved for initially empty form XObjects!



117
118
119
120
121
122
123
124
125
126
127
# File 'lib/hexapdf/type/form.rb', line 117

def canvas
  document.cache(@data, :canvas) do
    unless stream.empty?
      raise HexaPDF::Error, "Cannot create a canvas for a form XObjects with contents"
    end
    canvas = Content::Canvas.new(self)
    self.stream = canvas.stream_data
    set_filter(:FlateDecode)
    canvas
  end
end

#contentsObject

Returns the contents of the form XObject.

Note: This is the same as #stream but here for interface compatibility with Page.



78
79
80
# File 'lib/hexapdf/type/form.rb', line 78

def contents
  stream
end

#contents=(data) ⇒ Object

Replaces the contents of the form XObject with the given string.

Note: This is the same as #stream= but here for interface compatibility with Page.



85
86
87
# File 'lib/hexapdf/type/form.rb', line 85

def contents=(data)
  self.stream = data
end

#process_contents(processor, original_resources: nil) ⇒ Object

Processes the content stream of the form XObject with the given processor object.

The original_resources argument has to be set to a page’s resources if this form XObject is processed as part of this page.

See: HexaPDF::Content::Processor



100
101
102
103
104
105
106
107
108
109
# File 'lib/hexapdf/type/form.rb', line 100

def process_contents(processor, original_resources: nil)
  processor.resources = if self[:Resources]
                          self[:Resources]
                        elsif original_resources
                          original_resources
                        else
                          document.wrap({}, type: :XXResources)
                        end
  Content::Parser.parse(contents, processor)
end

#resourcesObject

Returns the resource dictionary which is automatically created if it doesn’t exist.



90
91
92
# File 'lib/hexapdf/type/form.rb', line 90

def resources
  self[:Resources] ||= document.wrap({}, type: :XXResources)
end