英語、ドイツ語の言語用レイヤーを定義して、set_layer_dependency 関数の parent オプションにより、階層構造を指定します。RGB と Grayscale のためのイメージレイヤーを定義して set_layer_dependency 関数の parant オプションによりお互いの階層構造を指定します。レイヤー上のイメージとテキストを出力して、RGB イメージと英語のキャプション表示のドキュメントを表示します。
/*
* Hierarchical layers:
* Define a layer hierarchy using the parent and child options.
*
* Define the layer "Languages" with the layers "English" and "German" and use
* set_layer_dependency() with the "parent" option to specify a hierarchy
* between them. Define the layer "Images" with the layers "RGB" and "Grayscale"
* and use set_layer_dependency() with the "parent" option to specify a
* hierarchy between them. Output images and text on the various layers and
* open the document with the RGB images and English captions visible.
*
* Required software: PDFlib/PDFlib+PDI/PPS 9
* Required data: grayscale and RGB images
*/
package com.pdflib.cookbook.pdflib.graphics;
import com.pdflib.pdflib;
import com.pdflib.PDFlibException;
public class hierarchical_layers
{
public static void main (String argv[])
{
/* This is where the data files are. Adjust as necessary. */
String searchpath = "../input";
String outfile = "hierarchical_layers.pdf";
String title = "Hierarchical Layers";
pdflib p = null;
String rgb = "nesrin.jpg";
String gray = "nesrin_gray.jpg";
int font, imageRGB, imageGray;
int layerImage, layerRGB, layerGray, layerLang, layerEN, layerDE;
int exitcode = 0;
try {
p = new pdflib();
p.set_option("searchpath={" + searchpath + "}");
/* This means we must check return values of load_font() etc. */
p.set_option("errorpolicy=return");
/* Open the document with the "Layers" navigation tab visible */
if (p.begin_document(outfile, "openmode=layers") == -1)
throw new Exception("Error: " + p.get_errmsg());
p.set_info("Creator", "PDFlib Cookbook");
p.set_info("Title", title);
/* Load the font */
font = p.load_font("Helvetica", "unicode", "");
if (font == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Load the Grayscale image */
imageGray = p.load_image("auto", gray, "");
if (imageGray == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Load the RGB image */
imageRGB = p.load_image("auto", rgb, "");
if (imageRGB == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Define all layers which will be used, and their relationships. This
* should be done before the first page if the layers are used on more
* than one page.
*/
/* Define the layer "Images" */
layerImage = p.define_layer("Images", "");
/* Define the layer "RGB" */
layerRGB = p.define_layer("RGB", "");
/* Define the layer "Grayscale" which is hidden when opening the
* document or printing it.
*/
layerGray = p.define_layer("Grayscale",
"initialviewstate=false initialprintstate=false");
/* At most one of the "Grayscale" and "RGB" layers will be visible */
p.set_layer_dependency("Radiobtn",
"group={" + layerGray + " " + layerRGB + "}");
/* Make the "Images" layer to be the parent of the "RGB" and "Grayscale"
* layers
*/
p.set_layer_dependency("Parent", "parent=" + layerImage +
" children={" + layerGray + " " + layerRGB + "}");
/* Define the layer "Languages" */
layerLang = p.define_layer("Languages", "");
/* Define the layer "English" */
layerEN = p.define_layer("English", "");
/* Define the layer "German" which is hidden when opening the document
* or printing it.
*/
layerDE = p.define_layer("German",
"initialviewstate=false initialprintstate=false");
/* At most one of the "English" and "German" layers will be visible */
p.set_layer_dependency("Radiobtn", "group={" + layerEN + " " +
layerDE + "}");
/* Make the "Languages" layer to be the parent of the "German" and
* "English" layers
*/
p.set_layer_dependency("Parent", "parent=" + layerLang +
" children={" + layerEN + " " + layerDE + "}");
/* Start the page */
p.begin_page_ext(0, 0, "width=a4.width height=a4.height");
/* Place the RGB image on the "RGB" layer */
p.begin_layer(layerRGB);
p.fit_image(imageRGB, 100, 400, "boxsize={400 300} fitmethod=meet");
/* Place the Grayscale image on the "Grayscale" layer */
p.begin_layer(layerGray);
p.fit_image(imageGray, 100, 400, "boxsize={400 300} fitmethod=meet");
/* Place an English image caption on the "English" layer */
p.begin_layer(layerEN);
p.fit_textline("This is the Nesrin image.", 100, 370, "font=" + font +
" fontsize=20");
/* Place a German image caption on the "German" layer */
p.begin_layer(layerDE);
p.fit_textline("Das ist das Nesrin-Bild.", 100, 370, "font=" + font +
" fontsize=20");
p.end_layer();
p.end_page_ext("");
p.end_document("");
} catch (PDFlibException e) {
System.err.println("PDFlib exception occurred:");
System.err.println("[" + e.get_errnum() + "] " + e.get_apiname() +
": " + e.get_errmsg());
exitcode = 1;
} catch (Exception e) {
System.err.println(e.toString());
exitcode = 1;
} finally {
if (p != null) {
p.delete();
}
System.exit(exitcode);
}
}
}