Makrand Mane

Wifi

The WifiManager can be used to enable and disable wifi.

WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wifi.setWifiEnabled(enabled);

GPS Location
we can use LocationManager to start up the GPS and get location updates.

LocationManager locator = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener mLocationListener = new LocationListener() {
  public void onLocationChanged(Location location) {
    if (location != null) {
      location.getAltitude();
      location.getLatitude();
      location.getLongitude();
      location.getTime();
      location.getAccuracy();
      location.getSpeed();
      location.getProvider();
    }
  }

  public void onProviderDisabled(String provider) {
    // ...
  }

  public void onProviderEnabled(String provider) {
    // ...
  }

  public void onStatusChanged(String provider, int status, Bundle extras) {
    // ...
  }
};

// You need to specify a Criteria for picking the location data source.
// The criteria can include power requirements.
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);  // Faster, no GPS fix.
criteria.setAccuracy(Criteria.ACCURACY_FINE);  // More accurate, GPS fix.
// You can specify the time and distance between location updates.
// Both are useful for reducing power requirements.
mLocationManager.requestLocationUpdates(mLocationManager.getBestProvider(criteria, true),
    MIN_LOCATION_UPDATE_TIME, MIN_LOCATION_UPDATE_DISTANCE, mLocationListener,
    getMainLooper());

we can also get the phone’s last known location using the LocationManager. This is faster than setting up a LocationListener and waiting for a fix.

// Start with fine location.
Location l = locator.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (l == null) {
  // Fall back to coarse location.
  l = locator.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}

SMS
we can send SMS by using SmsManager.

SmsManager sm = SmsManager.getDefault();
String destination = "+919822390027";
String text = "Hello, jony!";
sm.sendTextMessage(destination, null, text, null, null);

Vibrate
we can vibrate the phone for a specified duration

(Vibrator) getSystemService(Context.VIBRATOR_SERVICE).vibrate(milliseconds);

The application I’m currently working requires that the user has the GPS active on phone. otherwise application is useless. The application needs the Geodata to function. This brought up the issue of, how do we know if the user actually has the GPS enabled on the phone? If they don’t, the application will still work, but all values are zero. to avoid this we need to check GPS status.

This can be done by using locationManager. it has isProviderEnabled() method by using that we can check GPS status.

Here is code snippet.

protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.main);
     LocationManager locManager = (LocationManager) getSystemService(LOCATION_SERVICE);

     if (!locManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
          createGpsDisabledAlert();
     }
}

private void createGpsDisabledAlert(){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Your GPS is disabled! Would you like to enable it?")
     .setCancelable(false)
     .setPositiveButton("Enable GPS",
          new DialogInterface.OnClickListener(){
          public void onClick(DialogInterface dialog, int id){
               showGpsOptions();
          }
     });
     .setNegativeButton("Do nothing",
          new DialogInterface.OnClickListener(){
          public void onClick(DialogInterface dialog, int id){
               dialog.cancel();
          }
     });
AlertDialog alert = builder.create();
alert.show();
}

private void showGpsOptions(){
		Intent gpsOptionsIntent = new Intent(
				android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
		startActivity(gpsOptionsIntent);
}

And thats it! When the user starts the activity, if the GPS is off, the dialog will pop up asking them what they want to do. If the GPS is already on, nothing will happen.

Currently I am working on GPS related project. and every day I am exploring new things. Now I realize that GPS is very interesting technology and we can make lot of useful things by using GPS.

The new thing today I learned is, finding distance between two points. Previously I was thinking that, it may be difficult but, thankfully there is a much simpler way to figure out distances between two points on a map: the distanceTo() method in the Location class. Using this handy little method, we can quickly find out the distance between two locations:

double distance;

Location locationA = new Location("point A");

locationA.setLatitude(latA);
locationA.setLongitude(lngA);

Location locationB = new Location("point B");

locationB.setLatitude(latB);
LocationB.setLongitude(lngB);

distance = locationA.distanceTo(locationB);

One thing to note is that the distanceTo() method returns the distance in meters, so you will need to do the appropriate calculations if you want your distances in other units.