Imposition

1//---------------------------------------------------------------------------------------
2// Copyright (c) 2001-2019 by PDFTron Systems Inc. All Rights Reserved.
3// Consult legal.txt regarding legal and license information.
4//---------------------------------------------------------------------------------------
5
6package com.pdftron.android.pdfnetsdksamples.samples;
7
8import com.pdftron.android.pdfnetsdksamples.OutputListener;
9import com.pdftron.android.pdfnetsdksamples.PDFNetSample;
10import com.pdftron.android.pdfnetsdksamples.R;
11import com.pdftron.android.pdfnetsdksamples.util.Utils;
12import com.pdftron.pdf.Element;
13import com.pdftron.pdf.ElementBuilder;
14import com.pdftron.pdf.ElementWriter;
15import com.pdftron.pdf.PDFDoc;
16import com.pdftron.pdf.Page;
17import com.pdftron.pdf.PageIterator;
18import com.pdftron.pdf.Rect;
19import com.pdftron.sdf.SDFDoc;
20
21import java.util.ArrayList;
22
23//-----------------------------------------------------------------------------------
24//The sample illustrates how multiple pages can be combined/imposed
25//using PDFNet. Page imposition can be used to arrange/order pages
26//prior to printing or to assemble a 'master' page from several 'source'
27//pages. Using PDFNet API it is possible to write applications that can
28//re-order the pages such that they will display in the correct order
29//when the hard copy pages are compiled and folded correctly.
30//-----------------------------------------------------------------------------------
31
32public class ImpositionTest extends PDFNetSample {
33
34	private static OutputListener mOutputListener;
35
36	private static ArrayList<String> mFileList = new ArrayList<>();
37
38    public ImpositionTest() {
39        setTitle(R.string.sample_imposition_title);
40        setDescription(R.string.sample_imposition_description);
41    }
42
43	@Override
44	public void run(OutputListener outputListener) {
45		super.run(outputListener);
46		mOutputListener = outputListener;
47		mFileList.clear();
48		printHeader(outputListener);
49
50        String filein = Utils.getAssetTempFile(INPUT_PATH + "newsletter.pdf").getAbsolutePath();
51        String fileout = Utils.createExternalFile("newsletter_booklet.pdf", mFileList).getAbsolutePath();
52
53        mOutputListener.println("-------------------------------------------------");
54        mOutputListener.println("Opening the input pdf...");
55        try (PDFDoc in_doc = new PDFDoc(filein)) {
56            in_doc.initSecurityHandler();
57
58            // Create a list of pages to import from one PDF document to another.
59            Page[] copy_pages = new Page[in_doc.getPageCount()];
60            int j = 0;
61            for (PageIterator itr = in_doc.getPageIterator(); itr.hasNext(); j++) {
62                copy_pages[j] = itr.next();
63            }
64
65            try (PDFDoc new_doc = new PDFDoc()) {
66                Page[] imported_pages = new_doc.importPages(copy_pages);
67
68                // Paper dimension for A3 format in points. Because one inch has
69                // 72 points, 11.69 inch 72 = 841.69 points
70                Rect media_box = new Rect(0, 0, 1190.88, 841.69);
71                double mid_point = media_box.getWidth() / 2;
72
73                ElementBuilder builder = new ElementBuilder();
74                ElementWriter writer = new ElementWriter();
75
76                for (int i = 0; i < imported_pages.length; ++i) {
77                    // Create a blank new A3 page and place on it two pages from the input document.
78                    Page new_page = new_doc.pageCreate(media_box);
79                    writer.begin(new_page);
80
81                    // Place the first page
82                    Page src_page = imported_pages[i];
83                    Element element = builder.createForm(src_page);
84
85                    double sc_x = mid_point / src_page.getPageWidth();
86                    double sc_y = media_box.getHeight() / src_page.getPageHeight();
87                    double scale = sc_x < sc_y ? sc_x : sc_y; // min(sc_x, sc_y)
88                    element.getGState().setTransform(scale, 0, 0, scale, 0, 0);
89                    writer.writePlacedElement(element);
90
91                    // Place the second page
92                    ++i;
93                    if (i < imported_pages.length) {
94                        src_page = imported_pages[i];
95                        element = builder.createForm(src_page);
96                        sc_x = mid_point / src_page.getPageWidth();
97                        sc_y = media_box.getHeight() / src_page.getPageHeight();
98                        scale = sc_x < sc_y ? sc_x : sc_y; // min(sc_x, sc_y)
99                        element.getGState().setTransform(scale, 0, 0, scale, mid_point, 0);
100                        writer.writePlacedElement(element);
101                    }
102
103                    writer.end();
104                    new_doc.pagePushBack(new_page);
105                }
106
107                new_doc.save(fileout, SDFDoc.SaveMode.LINEARIZED, null);
108                mOutputListener.println("Done. Result saved in newsletter_booklet.pdf...");
109            }
110        } catch (Exception e) {
111            mOutputListener.printError(e.getStackTrace());
112        }
113
114		for (String file : mFileList) {
115			addToFileList(file);
116		}
117		printFooter(outputListener);
118	}
119
120}