Android Beacon Library

public class MonitoringActivity extends Activity {
    protected static final String TAG = "MonitoringActivity";
    private BeaconManager beaconManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_ranging);
                beaconManager = BeaconManager.getInstanceForApplication(this);
        // To detect proprietary beacons, you must add a line like below corresponding to your beacon
        // type.  Do a web search for "setBeaconLayout" to get the proper expression.
        // beaconManager.getBeaconParsers().add(new BeaconParser().
        //        setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));
        beaconManager.addMonitorNotifier(new MonitorNotifier() {
        @Override
        public void didEnterRegion(Region region) {
            Log.i(TAG, "I just saw an beacon for the first time!");
        }

        @Override
        public void didExitRegion(Region region) {
            Log.i(TAG, "I no longer see an beacon");
        }

        @Override
            public void didDetermineStateForRegion(int state, Region region) {
            Log.i(TAG, "I have just switched from seeing/not seeing beacons: "+state);
            }
        });

        beaconManager.startMonitoring(new Region("myMonitoringUniqueId", null, null, null));
    }

}

public class RangingActivity extends Activity {
    protected static final String TAG = "RangingActivity";
    private BeaconManager beaconManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_ranging);
        beaconManager = BeaconManager.getInstanceForApplication(this);
        // To detect proprietary beacons, you must add a line like below corresponding to your beacon
        // type.  Do a web search for "setBeaconLayout" to get the proper expression.
        // beaconManager.getBeaconParsers().add(new BeaconParser().
        //        setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));
        beaconManager.addRangeNotifier(new RangeNotifier() {
            @Override
            public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
                if (beacons.size() > 0) {
                    Log.i(TAG, "The first beacon I see is about "+beacons.iterator().next().getDistance()+" meters away.");
                }
            }
        });

        beaconManager.startRangingBeacons(new Region("myRangingUniqueId", null, null, null));
    }
}

    <application
        android:name="com.example.MyApplicationName"
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <!-- Note:  the singleInstance below is important to keep two copies of your activity from getting launched on automatic startup -->
        <activity
            android:launchMode="singleInstance"
            android:name="com.example.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>
    </application>

public class MyApplicationName extends Application implements MonitorNotifier {
    private static final String TAG = ".MyApplicationName";

    @Override
    public void onCreate() {
        super.onCreate();
        Log.d(TAG, "App started up");
        BeaconManager beaconManager = BeaconManager.getInstanceForApplication(this);
        // To detect proprietary beacons, you must add a line like below corresponding to your beacon
        // type.  Do a web search for "setBeaconLayout" to get the proper expression.
        // beaconManager.getBeaconParsers().add(new BeaconParser().
        //        setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25"));

        // wake up the app when any beacon is seen (you can specify specific id filers in the parameters below)
        Region region = new Region("com.example.myapp.boostrapRegion", null, null, null);
        BeaconManager.getInstanceForApplication(this).startMonitoring(region);
        BeaconManager.getInstanceForApplication(this).addMonitorNotifier(this);
    }

    @Override
    public void didDetermineStateForRegion(int arg0, Region arg1) {
        // Don't care
    }

    @Override
    public void didEnterRegion(Region arg0) {
        Log.d(TAG, "Got a didEnterRegion call");
        // This call to disable will make it so the activity below only gets launched the first time a beacon is seen (until the next time the app is launched)
        // if you want the Activity to launch every single time beacons come into view, remove this call.
        Region region = new Region("com.example.myapp.boostrapRegion", null, null, null);
        BeaconManager.getInstanceForApplication(this).stopMonitoring(region);
        Intent intent = new Intent(this, MainActivity.class);
        // IMPORTANT: in the AndroidManifest.xml definition of this activity, you must set android:launchMode="singleInstance" or you will get two instances
        // created when a user launches the activity manually and it gets launched from here.
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        this.startActivity(intent);
    }

    @Override
    public void didExitRegion(Region arg0) {
        // Don't care
    }
}

Beacon beacon = new Beacon.Builder()
        .setId1("2f234454-cf6d-4a0f-adf2-f4911ba9ffa6")
        .setId2("1")
        .setId3("2")
        .setManufacturer(0x0118)
        .setTxPower(-59)
        .setDataFields(Arrays.asList(new Long[] {0l}))
        .build();
BeaconParser beaconParser = new BeaconParser()
        .setBeaconLayout("m:2-3=beac,i:4-19,i:20-21,i:22-23,p:24-24,d:25-25");
BeaconTransmitter beaconTransmitter = new BeaconTransmitter(getApplicationContext(), beaconParser);
beaconTransmitter.startAdvertising(beacon);