Configuring an Extensions Bundle

Starting with Oxygen XML Author 10.3 version a single bundle was introduced acting as a provider for all other extensions. The individual extensions can still be set and if present they take precedence over the single provider, but this practice is being discouraged and the single provider should be used instead.

The extensions bundle is represented by the ro.sync.ecss.extensions.api.ExtensionsBundle class. The provided implementation of the ExtensionsBundle is instantiated when the rules of the Document Type Association defined for the custom framework match a document opened in the editor. Therefor references to objects which need to be persistent throughout the application running session must not be kept in the bundle because the next detection event can result in creating another ExtensionsBundle instance.

Note: The Javadoc documentation of the Author API used in the example files is available on the Oxygen XML Author website. Also it can be downloaded as a zip archive from the website.
  1. Create a new Java project, in your IDE. Create the lib folder in the Java project folder and copy in it the oxygen.jar file from the {oXygen_installation_directory}/lib folder.
  2. Create the class simple.documentation.framework.SDFExtensionsBundle which must extend the abstract class ro.sync.ecss.extensions.api.ExtensionsBundle.
    public class SDFExtensionsBundle extends ExtensionsBundle {
  3. A Document Type ID and a short description should be defined first by implementing the methods getDocumentTypeID and getDescription. The Document Type ID is used to uniquely identify the current framework. Such an ID must be provided especially if options related to the framework need to be persistently stored and retrieved between sessions.
    	public String getDocumentTypeID() {
        		return "Simple.Document.Framework.document.type";
    	}
    
    	public String getDescription() {
        		return "A custom extensions bundle used for the Simple Document" + 
                        "Framework document type";
    	}
  4. In order to be notified about the activation of the custom Author extension in relation with an opened document an ro.sync.ecss.extensions.api.AuthorExtensionStateListener should be implemented. The activation and deactivation events received by this listener should be used to perform custom initializations and to register / remove listeners like ro.sync.ecss.extensions.api.AuthorListener, ro.sync.ecss.extensions.api.AuthorMouseListener or ro.sync.ecss.extensions.api.AuthorCaretListener. The custom author extension state listener should be provided by implementing the method createAuthorExtensionStateListener.
    	public AuthorExtensionStateListener createAuthorExtensionStateListener() {
        		return new SDFAuthorExtensionStateListener();
    	}

    The AuthorExtensionStateListener is instantiated and notified about the activation of the framework when the rules of the Document Type Association match a document opened in the Author editor mode. The listener is notified about the deactivation when another framework is activated for the same document, the user switches to another mode or the editor is closed. A complete description and implementation of an ro.sync.ecss.extensions.api.AuthorExtensionStateListener can be found in the Implementing an Author Extension State Listener.

    If Schema Aware mode is active in Oxygen, all actions that can generate invalid content will be redirected toward the ro.sync.ecss.extensions.api.AuthorSchemaAwareEditingHandler. The handler can either resolve a specific case, let the default implementation take place or reject the edit entirely by throwing an ro.sync.ecss.extensions.api.InvalidEditException. The actions that are forwarded to this handler include typing, delete or paste.

    See the Implementing an Author Schema Aware Editing Handler section for more details about this handler.

  5. Customizations of the content completion proposals are permitted by creating a schema manager filter extension. The interface that declares the methods used for content completion proposals filtering is ro.sync.contentcompletion.xml.SchemaManagerFilter. The filter can be applied on elements, attributes or on their values. Responsible for creating the content completion filter is the method createSchemaManagerFilter. A new SchemaManagerFilter will be created each time a document matches the rules defined by the Document Type Association which contains the filter declaration.
    	public SchemaManagerFilter createSchemaManagerFilter() {
        		return new SDFSchemaManagerFilter();
    	}

    A detailed presentation of the schema manager filter can be found in Configuring a Content completion handler section.

  6. The Author supports link based navigation between documents and document sections. Therefore, if the document contains elements defined as links to other elements, for example links based on the id attributes, the extension should provide the means to find the referred content. To do this an implementation of the ro.sync.ecss.extensions.api.link.ElementLocatorProvider interface should be returned by the createElementLocatorProvider method. Each time an element pointed by a link needs to be located the method is invoked.
    	public ElementLocatorProvider createElementLocatorProvider() {
        		return new DefaultElementLocatorProvider();
    	}

    The section that explains how to implement an element locator provider is Configuring a Link target element finder.

  7. The drag and drop functionality can be extended by implementing the ro.sync.exml.editor.xmleditor.pageauthor.AuthorDnDListener interface. Relevant methods from the listener are invoked when the mouse is dragged, moved over, or exits the Author editor mode, when the drop action changes, and when the drop occurs. Each method receives the DropTargetEvent containing information about the drag and drop operation. The drag and drop extensions are available on Author mode for both Oxygen XML Author Eclipse plugin and standalone application. The Text mode corresponding listener is available only for Oxygen XML Author Eclipse plugin. The methods corresponding to each implementation are: createAuthorAWTDndListener, createTextSWTDndListener and createAuthorSWTDndListener.
    	public AuthorDnDListener createAuthorAWTDndListener() {
        		return new SDFAuthorDndListener();
    	}

    For more details about the Author drag and drop listeners see the Configuring a custom Drag and Drop listener section.

  8. Another extension which can be included in the bundle is the reference resolver. In our case the references are represented by the ref element and the attribute indicating the referred resource is location. To be able to obtain the content of the referred resources you will have to implement a Java extension class which implements the ro.sync.ecss.extensions.api.AuthorReferenceResolver. The method responsible for creating the custom references resolver is createAuthorReferenceResolver. The method is called each time a document opened in an Author editor mode matches the Document Type Association where the extensions bundle is defined. The instantiated references resolver object is kept and used until another extensions bundle corresponding to another Document Type is activated as result of the detection process.
    	public AuthorReferenceResolver createAuthorReferenceResolver() {
        		return new ReferencesResolver();
    	}

    A more detailed description of the references resolver can be found in the Configuring a References Resolver section.

  9. To be able to dynamically customize the default CSS styles for a certain ro.sync.ecss.extensions.api.node.AuthorNode an implementation of the ro.sync.ecss.extensions.api.StylesFilter can be provided. The extensions bundle method responsible for creating the StylesFilter is createAuthorStylesFilter. The method is called each time a document opened in an Author editor mode matches the document type association where the extensions bundle is defined. The instantiated filter object is kept and used until another extensions bundle corresponding to another Document Type is activated as a result of the detection process.
    	public StylesFilter createAuthorStylesFilter() {
        		return new SDFStylesFilter();
    	}

    See the Configuring CSS styles filter section for more details about the styles filter extension.

  10. In order to edit data in custom tabular format implementations of the ro.sync.ecss.extensions.api.AuthorTableCellSpanProvider and the ro.sync.ecss.extensions.api.AuthorTableColumnWidthProvider interfaces should be provided. The two methods from the ExtensionsBundle specifying these two extension points are createAuthorTableCellSpanProvider and createAuthorTableColumnWidthProvider.
    	public AuthorTableCellSpanProvider createAuthorTableCellSpanProvider() {
        		return new TableCellSpanProvider();
    	}
    	
    	public AuthorTableColumnWidthProvider 
              createAuthorTableColumnWidthProvider() {
        		return new TableColumnWidthProvider();
    	}

    The two table information providers are not reused for different tables. The methods are called for each table in the document so new instances should be provided every time. Read more about the cell span and column width information providers in Configuring a Table Cell Span Provider and Configuring a Table Column Width Provider sections.

    If the functionality related to one of the previous extension point does not need to be modified then the developed ro.sync.ecss.extensions.api.ExtensionsBundle should not override the corresponding method and leave the default base implementation to return null.

  11. Package the compiled class into a jar file.
  12. Copy the jar file into the frameworks / sdf directory.
  13. Add the jar file to the Author class path.
  14. Register the Java class by clicking on the Extensions tab. Press the Choose button and select from the displayed dialog the name of the class: SDFExtensionsBundle.
    Note: The complete source code can be found in the Simple Documentation Framework project, included in the Oxygen Author SDK zip available for download on the Oxygen XML Author website.