graphics/layers_and_bookmarks

 * Layers and bookmarks:

 * Define two layers and hide or show them via bookmarks

 *

 * Define two layers for English or German text. Create two bookmarks which

 * show the English or the German layer, respectively.

 *

 * Required software: PDFlib/PDFlib+PDI/PPS 7

 * Required data: none

 */

package com.pdflib.cookbook.pdflib.graphics;

import com.pdflib.pdflib;

import com.pdflib.PDFlibException;

public class layers_and_bookmarks

{

    public static void main (String argv[])

    {

    /* This is where the data files are. Adjust as necessary. */

    String searchpath = "../input";

    String outfile = "layers_and_bookmarks.pdf";

    String title = "Layers and Bookmarks";

    pdflib p = null;

    int font, action, layerEN, layerDE;

    try {

        p = new pdflib();

        p.set_parameter("SearchPath", searchpath);

        /* This means we must check return values of load_font() etc. */

        p.set_parameter("errorpolicy", "return");

        /* Open the document with the "Bookmarks" navigation tab visible */

        if (p.begin_document(outfile, "openmode=bookmarks") == -1)

            throw new Exception("Error: " + p.get_errmsg());

        p.set_info("Creator", "PDFlib Cookbook");

        p.set_info("Title", title + " $Revision: 1.2 $");

        /* Load the font */

        font = p.load_font("Helvetica-Bold", "unicode", "");

        if (font == -1) {

            throw new Exception("Error: " + p.get_errmsg());   

        }

        /* Start page */

        p.begin_page_ext(0, 0, "width=a4.width height=a4.height");

        /* Define the layer "English" and place some English text on it */

        layerEN = p.define_layer("English", "");

        p.begin_layer(layerEN);

        p.fit_textline("Our paper planes are the ideal way of passing the " +

            "time.", 30, 600, "font=" + font + " fontsize=20");

        /* Define the layer "German" which is hidden when opening the document

         * or printing it. Place a German image caption on that layer.

         */

        layerDE = p.define_layer("German", "initialviewstate=false " +

            "initialprintstate=false");

        p.begin_layer(layerDE);

        p.fit_textline("Unsere Papierflieger sind ein idealer Zeitvertreib.",

            30, 600, "font=" + font + " fontsize=20");

        /* At most one of the "English" and "German" layers should be visible */

        p.set_layer_dependency("Radiobtn", "group={" + layerEN + " " +

            layerDE + "}");

        /* Create a "SetOCGState" action which shows the English layer. Since

         * at most one layer may be visible we don't need to explicitly hide

         * the German layer.

         */

        action = p.create_action("SetOCGState", "layerstate={on " +

            layerEN + "}");

        /* Create a bookmark which activate the action above to shows the layer

         * with the English text

         */

        p.create_bookmark("Show English", " action={activate=" + action + "}");

        /* Create a "SetOCGState" action which shows the German layer. Since

         * at most one layer may be visible we don't need to explicitly hide

         * the English layer. */

        action = p.create_action("SetOCGState", "layerstate={on " +

            layerDE + "}");

        /* Create a bookmark which activate the action above to shows the layer

         * with the German text

         */

        p.create_bookmark("Show German", " action={activate=" + action + "}");

        /* Complete all layers */

        p.end_layer();

        p.end_page_ext("");

        p.end_document("");

        } catch (PDFlibException e) {

            System.err.print("PDFlib exception occurred:\n");

            System.err.print("[" + e.get_errnum() + "] " + e.get_apiname() +

                ": " + e.get_errmsg() + "\n");

        } catch (Exception e) {

            System.err.println(e.getMessage());

        } finally {

            if (p != null) {

                p.delete();

            }

        }

    }

}