Create QR Code Reader in Android with ZXing

Android is popular mobile phone OS. Sometime developer want to adding QR Code Scanner/Reader in the application they buid. I want to share my experience creating QR Code Reader in android using ZXing Barcode Scanner.
ZXing ("zebra crossing") is an open-source, multi-format 1D/2D barcode image processing library implemented in Java, with ports to other languages. ZXing project can be found on github https://github.com/zxing/zxing/.
Tutorial using ZXing in android I found great here. http://karanbalkar.com/2013/12/tutorial-65-implement-barcode-scanner-using-zxing-in-android/.

Step 1
Download ZXing. I download from here. Because I use from ZXing project master is not working.
https://gitorious.org/rowboat/external-zxing/source/7620644768ffc235607b3a94671e49518c18686f:qr_scanner

Step 2
Extract downloading file (rowboat-external-zxing folder) then import folder qr_scanner to eclipse.

Step 3
Create folder libs to the root project, then copy file core.jar from folder core (in rowboat-external-zxing folder) paste to folder libs. The project look like this. Set CaptureActivity project as library. (right-click) Properties -> Android -> Check Is Library.

Step 4
Create new android project application. (right click) Project –> Properties –> Android and add the ZXing project (CaptureActivity) as a library.

Step 5
Add the following code
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.project.tester.MainActivity" >
    <TextView
        android:id="@+id/result"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="" />
       <Button
        android:id="@+id/scan"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Scan"/>
</LinearLayout>

MainActivity.java
package com.project.tester;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

    TextView result;
    Button scan;
   
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       
        result=(TextView)findViewById(R.id.result);
        scan=(Button)findViewById(R.id.scan);
       
        scan.setOnClickListener(new View.OnClickListener() {
           
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent("com.google.zxing.client.android.SCAN");
                intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
                startActivityForResult(intent, 0);
            }
        });
       
    }

    public void onActivityResult(int requestCode, int resultCode, Intent intent) {
        if (requestCode == 0) {
            if (resultCode == RESULT_OK) {

                String contents = intent.getStringExtra("SCAN_RESULT");
                String format = intent.getStringExtra("SCAN_RESULT_FORMAT");
                result.setText("Format: "+format+"\nContent: "+contents);
                Toast.makeText(getApplicationContext(), "Format: "+format+"\nContent: "+contents,Toast.LENGTH_SHORT).show();
                // Handle successful scan

            } else if (resultCode == RESULT_CANCELED) {
                // Handle cancel
                // Log.i("App","Scan unsuccessful");
                Toast.makeText(getApplicationContext(), "Scan unsuccessful",Toast.LENGTH_SHORT).show();
            }
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
}


AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.project.tester"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="10" />

    <uses-permission android:name="android.permission.CAMERA" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name="com.google.zxing.client.android.CaptureActivity"
            android:configChanges="orientation|keyboardHidden"
            android:screenOrientation="landscape"
            android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
            android:windowSoftInputMode="stateAlwaysHidden" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
            <intent-filter>
                <action android:name="com.google.zxing.client.android.SCAN" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>
    </application>

</manifest>

 Finally, run the project on an Android device. Try scanning any QR code and you should see the desired result!

Complete code here(Dropbox)
Good Luck