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Android PDF Viewer library [closed]

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I know this question has been asked many times but it's still unclear for me if there is an existing and properly working library to natively display PDF documents.
I only want to view a PDF document which is stored inside my app. Opening a new Activity is ok for me, I don't need to display it inside an existing view. I've already built a piece of code to launch an activity intent for reading my local PDF file, but of course, if no PDF Viewer app is already installed on the device, then nothing happens.
I've heard about APV, VuDroid, droidreader, etc but it seems that they all are APKs, not libraries that can be used inside my app code.
So, is there any real Android library to achieve this?
Thanks in advance.

This one you can try it which works in offline mode
https://github.com/bitfield66/PdfViewerAndroid_Offline
which just accepts pdf path.

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)
So to do this we need this library. It is my edited version of this git.
After you have imported the library into your project you need to create your activity.
The XML:
<?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>
The java onCreate:
//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);
}
});
pdfLoadImages();//load images
}
Load Images:
private void pdfLoadImages()
{
try
{
// run async
new AsyncTask<Void, Void, Void>()
{
// create and show a progress dialog
ProgressDialog progressDialog = ProgressDialog.show(MainActivity.this, "", "Opening...");
#Override
protected void onPostExecute(Void result)
{
//after async close progress dialog
progressDialog.dismiss();
}
#Override
protected Void doInBackground(Void... params)
{
try
{
// select a document and get bytes
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/randompdf.pdf");
RandomAccessFile raf = new RandomAccessFile(file, "r");
FileChannel channel = raf.getChannel();
ByteBuffer bb = ByteBuffer.NEW(channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size()));
raf.close();
// create a pdf doc
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);
stream.close();
byte[] byteArray = stream.toByteArray();
//convert the byte array to a base64 string
String base64 = Base64.encodeToString(byteArray, Base64.DEFAULT);
//create the html + add the first image to the html
String html = "<!DOCTYPE html><html><body bgcolor=\"#7f7f7f\"><img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>";
//loop through 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);
stream = new ByteArrayOutputStream();
page.compress(Bitmap.CompressFormat.PNG, 100, stream);
stream.close();
byteArray = stream.toByteArray();
base64 = Base64.encodeToString(byteArray, Base64.DEFAULT);
html += "<img src=\"data:image/png;base64,"+base64+"\" hspace=10 vspace=10><br>";
}
html += "</body></html>";
//load the html in the webview
wv.loadDataWithBaseURL("", html, "text/html","UTF-8", "");
}
catch (Exception e)
{
Log.d("CounterA", e.toString());
}
return null;
}
}.execute();
System.gc();// run GC
}
catch (Exception e)
{
Log.d("error", e.toString());
}
}

I like the MuPDF Adnroid lib since it written in C++/NDK and it has unique features like clickable images (I mean an URL linked to the image) - met no other lib with this feature and I was really need it.
You actually can open PDF using no lib at all: using WebView via google docs but I don't like this way due to IC is required all the time while using MuPDF I can DL pdf file and freely open it offline any time. Also WebView way is more "hard" for device meaning battery draining + lags + CPU heating and it uses more trafic (if compared to DL&show way).

Set background color with text from url?

So i have an activity that imports a list of names from a .txt that is on a webserver.
But how do i set the background color? On the page that shows the names in the app?
Because it doesnt use the layout i set? Which is roster.xml
Do i have to do something to the .txt file?
Roster.class code:
package com.frede.iii;
import java.io.BufferedInputStream;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import org.apache.http.util.ByteArrayBuffer;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.view.Window;
import android.widget.ScrollView;
import android.widget.TextView;
public class IIIRoster extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.roster);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
// Scrollview
ScrollView sv = new ScrollView(this);
/* We will show the data we read in a TextView. */
TextView tv = new TextView(this);
/* Will be filled and displayed later. */
String myString = null;
try {
/* Define the URL we want to load data from. */
//http://androidtest.host.org/roster.txt
URL myURL = new URL(
"http://androidtest.host.org/roster.txt");
/* Open a connection to that URL. */
URLConnection ucon = myURL.openConnection();
/* Define InputStreams to read
* from the URLConnection. */
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
/* Read bytes to the Buffer until
* there is nothing more to read(-1). */
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while((current = bis.read()) != -1){
baf.append((byte)current);
}
/* Convert the Bytes read to a String. */
myString = new String(baf.toByteArray());
} catch (Exception e) {
/* On any Error we want to display it. */
myString = e.getMessage();
}
/* Show the String on the GUI. */
tv.setText(myString);
// Adds textview to scrollview
sv.addView(tv);
// Sets contentview to scrollview
this.setContentView(sv);
}
}

Hello you can simple use tv.setBackgroundColor(COLOR.XYX) or sv.setBackgroundColor(COLOR.XYX)
Also at the same time a textColor can be applied to text as tv.setTextColor(COLOR.XYX)
For defining you own colors to be used at run time, use the following:
1.In the string.xml file use the following tag
<color name="mycolor">#F5DC49</color>
Now in your code.
tv.setTextColor(getResources().getColor(R.color.mycolor))
2.Also we can set RGB values as:
tv.setTextColor(Color.rgb(170, 00, 00));

bad base64 in android

Hi i am using the following code to parse a certificate details.Everything is fine except a bit problem mentioned below.
package android.net.http;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileReader;
import java.io.InputStream;
import java.security.cert.Certif`enter code here`icate;
import java.security.cert.CertificateFactory;
import java.security.cert.CertificateParsingException;
import java.security.cert.X509Certificate;
import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.util.Base64;
import android.util.Base64InputStream;
import android.util.Log;
public class SslCertificate1Activity extends Activity
{
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try {
String text = "-----BEGIN CERTIFICATE-----\n"+
"MIIC/TCCAmagAwIBAgIBKjANBgkqhkiG9w0BAQQFADCBqDEiMCAGA1UEAxMZeG1sZ2F0ZXdheS5p\n"+
"dHMudXRleGFzLmVkdTEoMCYGA1UECxMfSW5mb3JtYXRpb24gVGVjaG5vbG9neSBTZXJ2aWNlczEq\n"+
"MCgGA1UEChMhVGhlIFVuaXZlcnNpdHkgb2YgVGV4YXMgYXQgQXVzdGluMQ8wDQYDVQQHEwZBdXN0\n"+
"aW4xDjAMBgNVBAgTBVRleGFzMQswCQYDVQQGEwJVUzAeFw0wNDA1MDkwNTMwMTBaFw0wNTA1MDQw\n"+
"NTMwMTBaMIGAMQswCQYDVQQGEwJVUzEOMAwGA1UECBMFVGV4YXMxDzANBgNVBAcTBkF1c3RpbjEq\n"+
"MCgGA1UEChMhVGhlIFVuaXZlcnNpdHkgb2YgVGV4YXMgYXQgQXVzdGluMRMwEQYDVQQLEwpUb29s\n"+
"cyBUZWFtMQ8wDQYDVQQDEwZDbGllbnQwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAJ6PABjb\n"+
"zXUkgo29S4uv1Qz9reo1/tP4pkQTGAldSbtA4hVtA/3sjw2+u3kgxYruAi2cXV2k0RPZhsUZjlDk\n"+
"jMPb/dlY81bD8gqe3lu3ezugJrlArlpfWN6PlufbTjxHSqIA0XD9R5/ZECaUV9dD43K5KdWUCy99\n"+
"YKDiSwVPO9F5AgMBAAGjXTBbMB0GA1UdDgQWBBRkCCpscEXxXu8Ba67p6zdh13ypjzAfBgNVHSME\n"+
"GDAWgBR2RsZH2kSY782kBROo92FAWS6sADAJBgNVHRMEAjAAMA4GA1UdDwQHAwUBEiRIkDANBgkq\n"+
"hkiG9w0BAQQFAAOBgQCtV1NzpdVBs5vyb8yLXNA3hA1LsmE/2QanXG4T3UN93BI4HQzx0idnkN1Y\n"+
"0RAQ1rjGeQ1pk3l2DWsPi9mTkCGmYs/EMLkKOBee9ad3BIG6sKwXgbgLyNLgda+Y1bo+SIomq/a7\n"+
"yP92UHMFEegfS/ssECA+Q3hHuU6in3AqLfWH1w==\n"+
"-----END CERTIFICATE-----";
int startIndex = 0;
String cert = text.substring(startIndex,text.length());
byte[] certBytes = cert.getBytes();
InputStream in = new Base64InputStream(new ByteArrayInputStream(
certBytes), 0);
CertificateFactory certFact = CertificateFactory.getInstance ("X.509");
Certificate certGen = certFact.generateCertificate(in);
X509Certificate x509 = (X509Certificate) certGen;
Log.i("","certificate details:"+x509);
}
catch (Exception e)
{
Log.e("testapp", "exception: " + e.getMessage());
}
}
}
and I am getting android.util.BASE64DataException:bad base-64 at the foloowing line when I launced debugger:-
Certificate certGen = certFact.generateCertificate(in);
Seems like there is something wrong with Base64InputStream.Please help in rectifying the Exception.
Thanks in advance

No, nothing is wrong with Base64InputStream. When in doubt, you should suspect your own code of being incorrect rather than everyone else's.
What's wrong is that you're giving Base64InputStream data that ends with "-----END CERTIFICATE-----" after the padding part.
You should only be passing in the bit between "-----BEGIN CERTIFICATE-----" and "-----END CERTIFICATE-----".
It looks like you've started thinking about that already here:
int startIndex = 0;
String cert = text.substring(startIndex,text.length());
... but that code isn't going to do anything - when startIndex is 0, substring is going to return the whole string...
Personally I'd consider doing the Base64 conversion first using the Base64 class to convert the base64 part of the string (you still need to get the substring) to a byte[] and then create a ByteArrayInputStream around that.

Retrieve data from sqlite database and display in assest folder's HTML page in android

I want to make a dynamic webpage that can display my sqlite database's element in tabular format. How can I create a dynamic webpage in android?
I make a static HTML page and put in assest folder. It works but now I want a dynamic webpage. Please help:
package com.Htmlview;
import java.io.IOException;
import java.io.InputStream;
import android.app.Activity;
import android.os.Bundle;
import android.webkit.WebView;
public class Htmlview extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.main);
WebView webview = new WebView(this);
setContentView(webview);
try {
InputStream fin = getAssets().open("index3.html");
byte[] buffer = new byte[fin.available()];
fin.read(buffer);
fin.close();
webview.loadData(new String(buffer), "text/html", "UTF-8");
} catch (IOException e) {
e.printStackTrace();
}
}
}
This page works ...
Help to make it dynamic through code.
gaurav gupta

Use java.text.MessageFormat:
Put "{0}" markers in your html file.
Read your html file into a string
Create an arguments array from the database record
Call MessageFormat.format(htmlString, dbArgs)
Load the resulting string into the webview.

You can't modify the asset folder in runtime as it compiled at build time. So, you have 2 variants:
You content from database as it is. Just read the bytes and pass them to the webview without storing to anywhere.
Store the content to the file in internal memory and do like you did it with assets. But there is no sence as you already have your data in db.

Android : Reading XML from local resource (for testing)

I'm writing an app which will read XML from a webservice (probably via kSOAP2). I'm fairly happy with SAX parsing, as I've done XML parsing iPhone apps.
Unfortunately the webservice isn't public yet so for initial testing I have some files containing the XML I need to parse. In this early dev phase I just need to read the XML from the files and pass it into the XML parser
Xml.parse(this.testXML, root.getContentHandler());
How do I read the XML from a file/resource into a string to pass into this method. I want to crack on and test the parser, but this simple step is holding me up.
Thanks

Create a raw folder under res
Put your XML file in there, eg. testXML.xml:
/res/raw/testXML.xml
You should be able to use your XML parser using that as an inputstream:
Xml.parse(getResources().openRawResource(R.raw.testXML), Xml.Encoding.UTF_8, root.getContentHandler());
Try that.

I found a solution. Using Assets.
Here is the simple code example of how I did it.
I know I could have used XmlPullParser to simply load an xml file from res, but I wanted to use SAX parsing. This allows me to simply throw an XML string into the SAX parser for testing before I plug in the webservice.
It just uses a simple view with a Button to kick off the file load and a TextView to display the XML for now. I can get on with my parser :)
package com.martins.XmlParserTest
import java.io.IOException;
import java.io.InputStream;
import android.app.Activity;
import android.content.res.AssetManager;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class Main extends Activity {
Button btn;
TextView tvXml;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button btn = (Button) findViewById(R.id.button1);
btn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// Load XML for parsing.
AssetManager assetManager = getAssets();
InputStream inputStream = null;
try {
inputStream = assetManager.open("textxml.xml");
} catch (IOException e) {
Log.e("tag", e.getMessage());
}
String s = readTextFile(inputStream);
TextView tv = (TextView)findViewById(R.id.textView1);
tv.setText(s);
}
});
}
private String readTextFile(InputStream inputStream) {
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
byte buf[] = new byte[1024];
int len;
try {
while ((len = inputStream.read(buf)) != -1) {
outputStream.write(buf, 0, len);
}
outputStream.close();
inputStream.close();
} catch (IOException e) {
}
return outputStream.toString();
}
}

Raises exception due to incorrectly formed XML (line1,Pos0).
You tell parser that the encoding is UTF-8 and if it isn't you may get various errors (depending on parsers). If you are using non-xml editor to edit your XML it may save the file in a different encoding regardless what you declared it to be in the XML document.