TUTORIALS

Creator Tutorial:

Adding a table of contents

As easy as 1, 2, 3...

What are PDF Outlines?

Outlines, also known as bookmarks or tables of content, are visual elements that allow users to navigate from one part of a document to another.

Outlines are presented to users as a tree-structured hierarchy of elements, each defining which page (or part of a page) to jump to  - while also displaying that they have been selected.

There are currently three types of items defined in the PDF Spec:

Basic Item	These items are only meant to add some visual separation in the outline tree as no specific task is executed when there are selected.
Destination Item	These items contain page index information that needs to be shown and, optionally, any zoom effect to be executed when showing it.
Action Item	These items contain the action to execute upon selection (usually a GotoAction that contains the same information as the Destination Item).

Programming outlines

In the following example, we will construct an outline similar to the image above.

// Create a new PDF document:
PdfDocument doc = new PdfDocument();

CreatorModule creatorModule = doc.getCreatorModule();

// Create a new page:
Page page = Page.createInstance(doc);

// Recover the page dimensions:
PageFormat pf = page.getPageFormat();
int page_y = (int) pf.getHeight();v

// Recover the object that allows the drawing of text on the page:
JPdfGraphics2D g2d = page.getGraphics();

//******************************************************
// Add the First chapter close to the top of the document.
//******************************************************

// Some text element in the page:
g2d.drawString("Chapter 1 Title", 15, 30 + g2d.getFontMetrics().getHeight());

// Create the destination and zoom data:
LocalPageDestination destination=LocalPageDestination.createInstance(doc);
destination.setPageIndex(1);
destination.setZoom(new ZoomPosition(new Integer(15), new Integer(30), null));

// Create the item:
OutlineItemDestination item0 = OutlineItemDestination.createInstance(doc);

// Set the title of the item and the destination upon activation:
item0.setTitle("Outline Chapter 1");
item0.setDestination(destination);

//******************************************************
// Add the subchapter in the middle of the document.
//******************************************************

// Some text element in the page:
g2d.drawString("Sub Chapter 1.1 Title", 15, page_y / 2 + g2d.getFontMetrics().getHeight());

// Create the destination and zoom data:
destination=LocalPageDestination.createInstance(doc);
destination.setPageIndex(1);
destination.setZoom(new ZoomPosition(new Integer(15), new Integer(page_y / 2), null));

// Create the item:
OutlineItemDestination item1 = OutlineItemDestination.createInstance(doc);

// Set the title of the item and the destination upon activation:
item1.setTitle("Outline SubChapter 1.1");
item1.setDestination(destination);

// Register it as a child of the first item:
item1.addBelow(item0);

//******************************************************
// Add the Second chapter close to the bottom of the document.
//******************************************************

// Some text element in the page:
g2d.drawString("Chapter 2 Title", 15, page_y - 30 + g2d.getFontMetrics().getHeight());

//Create the destination and zoom data:
destination=LocalPageDestination.createInstance(doc);
destination.setPageIndex(1);
destination.setZoom(new ZoomPosition(new Integer(15), new Integer(page_y - 30), null));

// Create the item:
OutlineItemDestination item2 = OutlineItemDestination.createInstance(doc);

// Set the title of the item and the destination upon activation:
item2.setTitle("Outline Chapter 2");
item2.setDestination(destination);

// Register it as a next item of the first item:
item2.addAfter(items0);

//Now register the outline in the document:
Outline outline = creatorModule.createOutline();
outline.addItem(items0);

// Important: DO NOT forget to dispose():
g2d.dispose();

Save the document and run the application

Final step: Save the document to a file and close it in order to release memory.

doc.saveAs("SimpleOutlineDemo.pdf");
doc.close();

The full source code of this tutorial is part of the distribution.
Please click on this link to display the generated PDF.