oXygen Author is highly customizable. Practically you can associate an entire class of documents (grouped logically by some common features like namespace, root element name or filename) to a bundle consisting of a CSS stylesheets, validation schemas, catalog files, templates for new files, transformation scenarios and even custom actions. This is called a Document Type Association.
In this section we will create a Document Type Association for a set of documents. As an example we will create a light documentation framework, similar to DocBook and create a complete customization of the Author editor.
You can find the complete files that were used in this tutorial in the Example Files Listings.
Our documentation framework will be very simple. The documents will be either articles
or books
, both composed of sections
. The sections
may contain titles
, paragraphs
, figures
, tables
and other sections
. To complete the picture, each section will include a def
element from another namespace.
The first schema file:
<?xml version="1.0" encoding="UTF-8"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.oxygenxml.com/sample/documentation" xmlns:doc="http://www.oxygenxml.com/sample/documentation" xmlns:abs="http://www.oxygenxml.com/sample/documentation/abstracts" elementFormDefault="qualified"> <xs:import namespace= "http://www.oxygenxml.com/sample/documentation/abstracts" schemaLocation= "abs.xsd"/>
The namespace of our documents will be http://www.oxygenxml.com/sample/documentation
. The namespace of the def
element is http://www.oxygenxml.com/sample/documentation/abstracts
.
Now let's define the structure of the sections. They all start with a title, then have the optional def
element then either a sequence of other sections, or a mixture of paragraphs, images and tables.
<xs:element name="book" type="doc:sectionType"/> <xs:element name="article" type="doc:sectionType"/> <xs:element name="section" type="doc:sectionType"/> <xs:complexType name="sectionType"> <xs:sequence> <xs:element name="title" type="xs:string"/> <xs:element ref="abs:def" minOccurs="0"/> <xs:choice> <xs:sequence> <xs:element ref="doc:section" maxOccurs="unbounded"/> </xs:sequence> <xs:choice maxOccurs="unbounded"> <xs:element ref="doc:para"/> <xs:element ref="doc:image"/> <xs:element ref="doc:table"/> </xs:choice> </xs:choice> </xs:sequence> </xs:complexType>
The paragraph contains text and other styling markup, such as bold (b
) and italic (i
) elements.
<xs:element name="para" type="doc:paragraphType"/> <xs:complexType name="paragraphType" mixed="true"> <xs:choice minOccurs="0" maxOccurs="unbounded"> <xs:element name="b"/> <xs:element name="i"/> </xs:choice> </xs:complexType>
The image
element has an attribute with a reference to the file containing image data.
<xs:element name="image"> <xs:complexType> <xs:attribute name="href" type="xs:anyURI" use="required"/> </xs:complexType> </xs:element>
The table
contains a header row and then a sequence of rows (tr
elements) each of them containing the cells. Each cell has the same content as the paragraphs.
<xs:element name="table"> <xs:complexType> <xs:sequence> <xs:element name="header"> <xs:complexType> <xs:sequence> <xs:element name="td" maxOccurs="unbounded" type="doc:paragraphType"/> </xs:sequence> </xs:complexType> </xs:element> <xs:element name="tr" maxOccurs="unbounded"> <xs:complexType> <xs:sequence> <xs:element name="td" type="doc:tdType" maxOccurs="unbounded"/> </xs:sequence> </xs:complexType> </xs:element> </xs:sequence> </xs:complexType> </xs:element> <xs:complexType name="tdType"> <xs:complexContent> <xs:extension base="doc:paragraphType"> <xs:attribute name="row_span" type="xs:integer"/> <xs:attribute name="column_span" type="xs:integer"/> </xs:extension> </xs:complexContent> </xs:complexType>
The def
element is defined as a text only element in the imported schema abs.xsd
:
<?xml version="1.0" encoding="UTF-8"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace= "http://www.oxygenxml.com/sample/documentation/abstracts"> <xs:element name="def" type="xs:string"/> </xs:schema>
Now that we defined our XML data structure, let's start styling it...
If you read the Simple Customization Tutorial then you already have some basic notions about creating simple styles. Our document contains elements from different namespaces, so we will use CSS Level 3 extensions supported by the oXygen layout engine to associate specific properties with that element.
Please note that the CSS Level 3 is a standard under development, and has not been released yet by the W3C. However, it addresses several important issues like selectors that are namespace aware and values for the CSS properties extracted from the attributes of the XML documents. Although not (yet) conforming with the current CSS standard these are supported by the oXygen Author.
We are now creating the basic layout of the rendered documents.
Elements that are stacked one on top of the other are: book
, article
, section
, title
, figure
, table
, image
. These elements are marked as having block
style for display. Elements that are placed one after the other in a flowing sequence are: b
, i
. These will have inline
display.
/* Vertical flow */ book, section, para, title, image, ref { display:block; } /* Horizontal flow */ b,i { display:inline; }
Having block
display children in an inline
display parent, makes oXygen Author change the style of the parent to block
display.
The title of any section must be bold and smaller than the title of the parent section. To create this effect we have to create a sequence of CSS rules. The *
operator matches any element, so we can use it to match titles having progressive depths in the document.
title{ font-size: 2.4em; font-weight:bold; } * * title{ font-size: 2.0em; } * * * title{ font-size: 1.6em; } * * * * title{ font-size: 1.2em; }
CSS rules are combined as follows:
All the rules that match an element are kept as a list. The more specific the rule is, the further it will be placed to the end of the list.
If there is no difference in the specificity of the rules, they are placed in the list in the same order as they appear in the CSS document.
The list is then iterated, and all the properties from the rules are collected, overwriting the already collected values from the previous rules. That is why the font-size is changed depending on the depth of the element, while the font-weight property remains unchanged - no other rule is overwriting it.
It's useful to have before the title a constant text, indicating that it refers to a section. This text can include also the current section number. To achieve we have to use the :before
and :after
pseudo elements, plus the CSS counters.
We declare a counter named sect
for each book
or article
. The counter is set to zero at the beginning of each such element:
book, article{ counter-reset:sect; }
The sect
counter is incremented with each section
, that is the a direct child of a book
or an article
element.
book > section, article > section{ counter-increment:sect; }
The "static" text that will prefix the section title is composed of the constant "Section ", followed by the decimal value of the sect
counter and a dot.
book > section > title:before, article > section > title:before{ content: "Section " counter(sect) ". "; }
To make the documents easy to read, we will add a margin to the sections. In this way the higher nesting level, the larger the left side indent. The margin is expressed relatively to the parent bounds:
section{ margin-left:1em; margin-top:1em; }
In the above screenshot you can see a sample XML document rendered by our CSS. The selection "avoids" the text that is generated by the CSS "content" property. This happens because the CSS generated text is not present in the XML document and is just a visual aid.
There are standard CSS properties used to indicate what elements are tables, table rows and table cells. What CSS is missing is the possibility to indicate the cell spanning. oXygen Author offers support for adding an extension to solve this problem. This will be presented in the next chapters.
The table in this example is a simple one. The header must be formatted in a different way than the ordinary rows, so it will have a background color.
table{ display:table; border:1px solid navy; margin:1em; } tr, header{ display:table-row; } header{ background-color: silver; color:inherit } td{ display:table-cell; border:1px solid navy; padding:1em; }
Children elements with block
or table-caption
display placed at the beginning or the end of an element displayed as a table
, will be grouped and presented as blocks at the top or the bottom of the table.
Mixing elements having table-cell
, table-group
, table-row
, etc.. display type with others that have block
or inline
display or with text content breaks the layout of the table. In such cases the table is shown as a block
.
Having child elements that do not have table-cell
or table
display in a parent with table-row
display breaks the table layout. In this case the table
display is supported for the children of the table-row
element in order to allow sub-tables in the parent table.
oXygen Author can automatically detect the spanning of a cell, without the need to write a Java extension for this.
This happens if the span of the cell element is specified using the colspan and rowspan attributes, just like in HTML, or cols and rows attributes.
For instance, the following XML code:
<table> <tr> <td>Cell 1.1</td> <td>Cell 1.2</td> <td>Cell 1.3</td> </tr> <tr> <td>Cell 2.1</td> <td colspan="2" rowspan="2"> Cell spanning 2 rows and 2 columns. </td> </tr> <tr><td>Cell 3.1</td></tr> </table>
using the CSS:
table{ display: table; } tr{ display: table-row; } td{ display: table-cell; }
is rendered correctly:
Table 7.1. Built-in Cell Spanning
Cell 1.1 | Cell 1.2 | Cell 1.3 |
Cell 2.1 | Cell spanning 2 rows and 2 columns | |
Cell 3.1 |
Because in our schema the td
tag has the attributes row_span and column_span that are not automatically recognized by oXygen Author, we will implement a Java extension which will provide information about the cell spanning. See the section Configuring a Table Cell Span Provider.
The "bold" style is obtained by using the font-weight
CSS property with the value bold
, while the "italic" style is specified by the font-style
property:
b { font-weight:bold; } i { font-style:italic; }
In the CSS Level 1, 2, and 2.1 there is no way to specify if an element X from the namespace Y should be presented differently from the element X from the namespace Z. In the upcoming CSS Level 3, it is possible to differentiate elements by their namespaces. oXygen Author supports this CSS Level 3 functionality. For more information see the Namespace Selectors section.
To match our def
element we will declare its namespace, bind it to the abs prefix, and then write a CSS rule:
@namespace abs "http://www.oxygenxml.com/sample/documentation/abstracts"; abs|def{ font-family:monospace; font-size:smaller; } abs|def:before{ content:"Definition:"; color:gray; }
The CSS 2.1 does not specify how an element can be rendered as an image. To overpass this limitation, oXygen Author supports a CSS Level 3 extension allowing to load image data from an URL. The URL of the image must be specified by one of the element attributes.
oXygen Author recognizes the following image file formats: JPEG, GIF, PNG and SVG. The oXygen Author for Eclipse does not render the SVG files.
image{ display:block; content: attr(href, url); margin-left:2em; }
Our image
element has the required attribute href
of type xs:anyURI
. The href
attribute contains an image location so the rendered content is obtained by using the function:
attr(href, url)
The first argument is the name of the attribute pointing to the image file. The second argument of the attr
function specifies the type of the content. If the type has the url
value, then oXygen identifies the content as being an image. If the type is missing, then the content will be the text representing the attribute value.
oXygen Author handles both absolute and relative specified URLs. If the image has an absolute URL location (e.g: "http://www.oasis-open.org/images/standards/oasis_standard.jpg") then it is loaded directly from this location. If the image URL is relative specified to the XML document (e.g: "images/my_screenshot.jpg") then the location is obtained by adding this value to the location of the edited XML document.
An image can also be referenced by the name of a DTD entity which specifies the location of the image file. For example if the document declares an entity graphic which points to a JPEG image file:
<!ENTITY graphic SYSTEM "depo/keyboard_shortcut.jpg" NDATA JPEG>
and the image is referenced in the XML document by specifying the name of the entity as the value of an attribute:
<mediaobject> <imageobject> <imagedata entityref="graphic" scale="50"/> </imageobject> </mediaobject>
the CSS should use the functions url, attr and unparsed-entity-uri for displaying the image in the Author mode:
imagedata[entityref]{ content: url(unparsed-entity-uri(attr(entityref))); }
You can specify what elements are collapsible. The collapsible elements are rendered having a small triangle icon in the top left corner. Clicking on this icon hides or shows the children of the element. In our case, we will mark the section
elements as foldable. We will leave only the title
child elements visible.
section{ foldable:true; not-foldable-child: title; }
You can specify what elements are links. The text content specified in the :before
pseudo element will be underlined. When hovering the mouse over that content the mouse pointer will change to indicate that it can follow the link. Clicking on a link will result in the referred resource being opened in an editor. In our case we will mark the link
elements as links with the href
attribute indicating the referred location.
link[href]:before{ display:inline; link:attr(href); content: "Click to open: " attr(href); }
If you plan to use IDs as references for links, the value of the link property should start with a sharp sign(#). This will ensure that the default link target reference finder implementation will work and clicking on the link will send you to the indicated location in the document. For more details about the link target reference finder read the section Configuring a Link target reference finder.
Example 7.1. IDs as references for links
link[linkend]:before{ display:inline; link: "#" attr(linkend); content: "Click to open: " attr(linkend); }
Now that we have the XML Schema and the CSS stylesheet for the documents we intend to edit, we can proceed to create a distributable framework package for our content authors.
First create a new folder called sdf
(from "Simple Documentation Framework") in {oXygen_installation_directory}/frameworks
. We will use this folder to store all files related to our documentation framework. Let's organise it a bit, by creating the following folder structure:
oxygen frameworks sdf schema css
The frameworks
directory is the container where all the oXygen framework customizations are located.
Each subdirectory contains files related to a specific type of XML documents: schemas, catalogs, stylesheets, CSS files, etc.
Distributing a framework means delivering a framework directory.
We assume you have the right to create files and folder inside the oXygen installation directory. If you do not have this right, you will have to install another copy of the program in a folder you have access to, the home directory for instance, or your desktop. You can download the "all platforms" distribution from the oXygen website and extract it in the chosen folder.
To test your framework distribution you will need to copy it in the frameworks
directory of the newly installed application and start oXygen by running the provided start-up script files.
We should copy the created schema files abs.xsd
and sdf.xsd
, sdf.xsd
being the master schema, to the schema
directory and the CSS file sdf.css
to the css
directory.
We must specify when oXygen should use the files created in the previous section by creating a document type association. Open the Document Type dialog by following the procedure:
Open the Options Dialog, and select the Document Types Association option pane.
Select the Developer user role from the User role combo box at the top of the dialog. This is important, because it will allow us to save the document type association in a file on disk, instead of oXygen options.
Click on the New button.
In the displayed dialog, fill in the following data:
Enter SDF - This is the name of the document type.
Enter Simple Documentation Framework - This is a short description helping the other users understand the purpose of the Document Type.
The storage refers to the place where the Document Type settings are stored.
means the Document Types are stored in the default oXygen preferences file. Since we want to share the Document Type to other users, we must select , and choose a file.The file must be in the {oXygen_installation_directory}/frameworks/sdf
directory. A possible location is /Users/{user_name}/Desktop/oxygen/frameworks/sdf/sdf.framework. The framework directory structure will be:
oxygen frameworks sdf sdf.framework schema sdf.xsd css sdf.css
If a document opened in oXygen matches one of the rules defined for the Document Type, then it is activated.
Press the http://www.oxygenxml.com/sample/documentation
. The root name, file name or PublicID are not relevant.
Beside the Namespace, Root local name, File name and Public ID, optionally, you can specify the name of a Java class. This class has access to all root element attributes and the above values in order to decide if the document matches the rule.
An alternative to the rule we defined for our association is to write the entire logic in Java.
Create a new Java project, in your IDE.
Create the lib
directory in the Java project directory and copy there the oxygen.jar
file from the {oXygen_installation_directory}/lib
. The oxygen.jar
contains the Java interfaces we have to implement and the available Author API needed to access its features.
Create the class simple.documentation.framework.CustomRule
. This class must implement the ro.sync.ecss.extensions.api.DocumentTypeCustomRuleMatcher
interface.
The interface defines two methods: matches
, and getDescription
.
The matches
method is the one that is invoked when the edited document must be checked against the document type association. It takes as arguments the root local name, its namespace, the document location URI, the PublicID and the root element attributes. It must return true
when the document matches the association.
The getDescription
method returns a description of the rule.
Here is the implementation of these two methods. The implementation of matches
is just a Java equivalent of the rule we defined earlier.
public boolean matches( String systemID, String rootNamespace, String rootLocalName, String doctypePublicID, Attributes rootAttributes) { return "http://www.oxygenxml.com/sample/documentation" .equals(rootNamespace); } public String getDescription() { return "Checks if the current Document Type Association" + " is matching the document."; }
The complete source code is found in the Example Files Listings, the Java Files section.
Package the compiled class into a jar file. Here is an example of an ANT script that packages the classes
directory content into a jar archive named sdf.jar
:
<?xml version="1.0" encoding="UTF-8"?> <project name="project" default="dist"> <target name="dist"> <jar destfile="sdf.jar" basedir="classes"> <fileset dir="classes"> <include name="**/*"/> </fileset> </jar> </target> </project>
Copy the sdf.jar
file into the frameworks/sdf
directory.
Add the sdf.jar
to the Author classpath. To do this select SDF Document Type from the Document Type Association options page and press the button.
Select the Classpath tab in the lower part of the dialog.
Press the frameworks
directory. If you are in the process of developing the extension actions you can also specify a path to a directory which holds compiled Java classes.
Clear the rules we defined before by using the
button.Press the
button from the Rules section.Press the Java class value. The following dialog is displayed:
button that follows theTo test the association, open the sdf.xml
sample and validate it.
In the dialog for editing the Document Type properties, in the bottom section there are a series of tabs. The first one refers to the schema that is used for validation of the documents that match the defined association Rules.
If the document refers a schema, using for instance a DOCTYPE
declaration or a xsi:schemaLocation
attribute, the schema from the document type association will not be used when validating.
Select from the combo box the value XML Schema.
Enter the value ${frameworks}/sdf/schema/sdf.xsd
. We should use the ${frameworks}
editor variable in the schema URI path instead of a full path in order to be valid for different oXygen installations.
The ${frameworks}
variable is expanded at the validation time into the absolute location of the directory containing the frameworks.
Select the
tab from the Document Type edit dialog. By clicking on the label in the right part of the tab the list of associated CSS files is shown.Here you can also specify how should the CSSs defined in the document type be treated when there are CSSs specified in the document(with xml-stylesheet
processing instructions). The CSSs from the document can either replace the CSSs defined in the document type association or merge with them.
Add the URI of the CSS file sdf.css
we already defined. We should use the ${frameworks}
editor variable in the file path.
The Title text field refers to a symbolic name for the stylesheet. When adding several stylesheets with different titles to a Document Type association, the content author can select what CSS will be used for editing from the Author CSS Alternatives toolbar.
This combo-box from the toolbar is also populated in case your XML document refers CSS files directly using xml-stylesheet
processing instructions, and the processing instructions define titles for the CSS files.
The CSS settings dialog allows to create a virtualxml-stylesheet
processing instructions. The CSS files defined in the Document Type Association dialog and the xml-stylesheet
processing instructions from the XML document are processed together, as being all a list of processing instructions.
oXygen Author fully implements the W3C recommendation regarding "Associating Style Sheets with XML documents". For more information see: http://www.w3.org/TR/xml-stylesheet/http://www.w3.org/TR/REC-html40/present/styles.html#h-14.3.2
To test the new Document Type create an XML instance that is conforming with our Simple Document Format. We will not specify an XML Schema location directly in the document, using an xsi:schemaLocation
attribute; oXygen will detect instead its associated document type and use the specified schema.
<book xmlns="http://www.oxygenxml.com/sample/documentation" xmlns:abs="http://www.oxygenxml.com/sample/documentation/abstracts"> <title>My Technical Book</title> <section> <title>XML</title> <abs:def>Extensible Markup Language</abs:def> <para>In this section of the book I will explain different XML applications.</para> </section> </book>
When trying to validate the document there should be no errors. Now modify the title
to title2
. Validate again. This time there should be one error:
cvc-complex-type.2.4.a: Invalid content was found starting with element 'title2'. One of '{"http://www.oxygenxml.com/sample/documentation":title}' is expected.
Undo the tag name change. Press on the
button at the bottom of the editing area. oXygen should load the CSS from the document type association and create a layout similar to this:Using a file explorer, go to the oXygen frameworks
directory. Select the sdf
directory and make an archive from it. Move it to another oXygen installation (eventually on another computer). Extract it in the frameworks
directory. Start oXygen and test the association as explained above.
If you create multiple document type associations and you have a complex directory structure it might be easy from the deployment point of view to use an oXygen all platforms distribution. Add your framework files to it, repackage it and send it to the content authors.
When deploying your customized sdf directory please make sure that your sdf directory contains the sdf.framework file (that is the file defined as External Storage in Document Type Association dialog shall always be stored inside the sdf directory). If your external storage points somewhere else <oXygen/> will not be able to update the Document Type Association options automatically on the deployed computers.