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copied!<p>I solved this issue. it's as simple as letting the device have time to render each page.</p> <p>To fix this all you have to do is change </p> <pre><code>PDFPage page = pdf_file.getPage(2); </code></pre> <p>to</p> <pre><code>PDFPage page = pdf_file.getPage(2, true); </code></pre> <p>Firstly to view a PDF in Android you have to convert the PDF into images then display them to the user. (I am going to use a webview)</p> <p>So to do this we need this <a href="https://github.com/StEaLtHmAn/AndroidPDFViewerLibrary" rel="nofollow noreferrer">library</a>. It is my edited version of this <a href="https://github.com/jblough/Android-Pdf-Viewer-Library" rel="nofollow noreferrer">git</a>.</p> <p>After you have imported the library into your project you need to create your activity.</p> <p>The XML:</p> <pre><code><?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <WebView android:id="@+id/webView1" android:layout_width="match_parent" android:layout_height="match_parent"/> </LinearLayout> </code></pre> <p>The java:</p> <pre><code>//Imports: import android.app.Activity; import android.app.ProgressDialog; import android.content.Intent; import android.graphics.Bitmap; import android.os.AsyncTask; import android.os.Bundle; import android.os.Environment; import android.util.Base64; import android.util.Log; import android.view.View; import android.view.ViewTreeObserver; import android.webkit.WebView; import com.sun.pdfview.PDFFile; import com.sun.pdfview.PDFImage; import com.sun.pdfview.PDFPage; import com.sun.pdfview.PDFPaint; import net.sf.andpdf.nio.ByteBuffer; import net.sf.andpdf.refs.HardReference; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.RandomAccessFile; import java.nio.channels.FileChannel; //Globals: private WebView wv; private int ViewSize = 0; //OnCreate Method: @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //Settings PDFImage.sShowImages = true; // show images PDFPaint.s_doAntiAlias = true; // make text smooth HardReference.sKeepCaches = true; // save images in cache //Setup webview wv = (WebView)findViewById(R.id.webView1); wv.getSettings().setBuiltInZoomControls(true);//show zoom buttons wv.getSettings().setSupportZoom(true);//allow zoom //get the width of the webview wv.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() { @Override public void onGlobalLayout() { ViewSize = wv.getWidth(); wv.getViewTreeObserver().removeGlobalOnLayoutListener(this); } }); try { File file = new File(Environment.getExternalStorageDirectory().getPath() + "/randompdf.pdf"); RandomAccessFile f = new RandomAccessFile(file, "r"); byte[] data = new byte[(int)f.length()]; f.readFully(data); pdfLoadImages(data); } catch(Exception ignored) { } } //Load Images: private void pdfLoadImages(final byte[] data) { try { // run async new AsyncTask<Void, Void, String>() { // create and show a progress dialog ProgressDialog progressDialog = ProgressDialog.show(MainActivity.this, "", "Opening..."); @Override protected void onPostExecute(String html) { //after async close progress dialog progressDialog.dismiss(); //load the html in the webview wv.loadDataWithBaseURL("", html, "text/html","UTF-8", ""); } @Override protected String doInBackground(Void... params) { try { //create pdf document object from bytes ByteBuffer bb = ByteBuffer.NEW(data); PDFFile pdf = new PDFFile(bb); //Get the first page from the pdf doc PDFPage PDFpage = pdf.getPage(1, true); //create a scaling value according to the WebView Width final float scale = ViewSize / PDFpage.getWidth() * 0.95f; //convert the page into a bitmap with a scaling value Bitmap page = PDFpage.getImage((int)(PDFpage.getWidth() * scale), (int)(PDFpage.getHeight() * scale), null, true, true); //save the bitmap to a byte array ByteArrayOutputStream stream = new ByteArrayOutputStream(); page.compress(Bitmap.CompressFormat.PNG, 100, stream); byte[] byteArray = stream.toByteArray(); stream.reset(); //convert the byte array to a base64 string String base64 = Base64.encodeToString(byteArray, Base64.NO_WRAP); //create the html + add the first image to the html String html = "<!DOCTYPE html><html><body bgcolor=\"#b4b4b4\"><img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>"; //loop though the rest of the pages and repeat the above for(int i = 2; i <= pdf.getNumPages(); i++) { PDFpage = pdf.getPage(i, true); page = PDFpage.getImage((int)(PDFpage.getWidth() * scale), (int)(PDFpage.getHeight() * scale), null, true, true); page.compress(Bitmap.CompressFormat.PNG, 100, stream); byteArray = stream.toByteArray(); stream.reset(); base64 = Base64.encodeToString(byteArray, Base64.NO_WRAP); html += "<img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>"; } stream.close(); html += "</body></html>"; return html; } catch (Exception e) { Log.d("error", e.toString()); } return null; } }.execute(); System.gc();// run GC } catch (Exception e) { Log.d("error", e.toString()); } } </code></pre>

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