Home > FixedLayout

Fixed-Layout Documents

Since v0.1.4, EPUB Parser supports Fixed-Layout Documents by EPUB::Publication::FixedLayout module. It is set "on" when rendition property exists in prefix attribute of package element in rootfile.

EPUB Fixed-Layout defines some additional properties to see how to render Content Documents. This EPUB Parser library supports it by providing convenience methods to know how to render.

Methods for EPUB::Publication::Package

#using_fixed_layout

It is true when package@prefix attribute has rendition property.

parser = EPUB::Parser::Publication.new(<<OPF)
<package version="3.0"
         unique-identifier="pub-id"
         xmlns="http://www.idpf.org/2007/opf"
         prefix="rendition: http://www.idpf.org/vocab/rendition/#">
</package>
OPF
package = parser.parse_package
package.using_fixed_layout # => true

And you can set by yourself:

package.using_fixed_layout = true
package.prefix # => {"rendition"=>"http://www.idpf.org/vocab/rendition/#"}

Common Methods

Methods below are provided for

#rendition_layout, #rendition_orientation and #rendition_spread

rendition:xxx property is specified by meta elements in /package/metadata and properties attribute of /package/spine/itemref elements in EPUB Publications. You are recommended to use rendition_xxx attribute to set them although you can do it by manipulating EPUB::Publication::Package::Metadata and EPUB::Publication::Package::Spine::Itemrefs directly. It is the reason why it is recommended that you must manipulate some objects not only one object to set a document's rendition:layout to, for instance, reflowable; Metadata::Meta and Spine::Itemref#properties. It is bothered and tends to be mistaken, so you're strongly recommended to use not them but rendition_layout.

Usage is simple. Just read and write attribute values.

metadata.rendition_layout # => "reflowable"
metadata.rendition_layout = 'pre-paginated'
metadata.rendition_layout # => "pre-paginated"

itemref.rendition_layout # => "pre-paginated"
itemref.rendition_layout = "reflowable"
itemref.rendition_layout # => "reflowable"

These methods are defined for EPUB::Publication::Package::Metadata, EPUB::Publication::Package::Spine::Itemref, EPUB::Publication::Package::Manifest::Item and EPUB::ContentDocument::XHTML. Methods for Metadata and Itemref are primary and ones for Item and ContentDocument are simply delegated to Itemref.

aliases

Each attribute rendition_xxx has alias attribute as just xxx.

metadata.orientation = 'portrait'
metadata.orientation # => "portrait"
metadata.rendition_orientation # => "portrait"

#reflowable? and #pre_paginated?

Predicate methods #reflowable? and #pre_paginated? which are shortcuts for comparison rendition_layout to arbitrary property value.

itemref.rendition_layout = 'pre-paginated'
itemref.reflowable? # => false
itemref.pre_paginated? # => true

#make_reflowable and make_pre_paginated

#make_reflowable(alias: #reflowable!) and #make_pre_paginated(alias: #pre_paginated!) can be used instead of calling rendition_layout and comparing it with String "reflowable" or "pre-paginated", they help you from mistyping such like "pre_paginated"(using underscore rather than hyphen).

Methods for EPUB::Publication::Package::Spine::Itemref

#page_spread

FixedLayout module adds property center to EPUB::Publication::Package::Spine::Itemref#page_spread's available properties, which are ever left and right.

itemref.page_spread # => nil
itemref.page_spread = 'center'
itemref.page_spread # => "center"
itemref.properties # => ["rendition:page-spread-center"]

References