2. Location, Media and Notification The object that handles any
reference to the location of the Android framework is the
LocationManager. This is recovered by the method
Context.getSystemService(): LocationManager locationManager =
(LocationManager) getSystemService(Context.LOCATION_SERVICE); This
allows to: Perform query to find out the last known position of the
LocationProvider Register a listener for location updates Register
a Receiver to notify the proximity of a given latitude/longitude.
Location API
3. Location, Media and Notification In a terminal there are 3
Provider for location: LocationManager.GPS_PROVIDER: GPS
localization. Permission required ACCESS_FINE_LOCATION
LocationManager.NETWORK_PROVIDER: network localization (WiFi or
cell). Permission required ACCESS_COARSE_LOCATION
LocationProvider.PASSIVE_PROVIDER: passive localization, active
when other applications or services request a localization update.
Permission required ACCESS_FINE_LOCATION Location API -
Location
4. Location, Media and Notification To obtain the current
position detected by the Provider, use the method
LocationManager.getLastKnownPosition() Location location =
locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER); The Location
object contains all the position data: double latitude =
location.getLatitude(); double longitude = location.getLongitude();
double altitude = location.getAltitude(); float bearing =
location.getBearing(); float speed = location.getSpeed(); float
accuracy = location.getAccuracy(); long time = location.getTime();
Location API - Location
5. Location, Media and Notification LocationListener
locationListener = new LocationListener() { public void
onLocationChanged(Location location) { } public void
onStatusChanged(String provider, int status, Bundle extras) { }
public void onProviderEnabled(String provider) { } public void
onProviderDisabled(String provider) { } };
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 0, 0, locationListener); Updates
can be restricted by a minimum distance and a minimum time interval
specification in the method:
manager.requestLocationUpdates(provider, minTime, minDistance,
listener); Location API Location Update
6. Location, Media and Notification The object used for playing
Audio and Video is the MediaPlayer. After indicating to the player
the source of the media content, using the method
MediaPlayer.setDataSource(), you must specify how to prepare the
content: MediaPlayer.prepare(): for local sources (no need of
background operations) MediaPlayer.prepareAsync(): for remote
contents (you need an external connection, so long running
operation to play them). After preparing, the MediaPlayer.start()
methos is called. Media
7. Location, Media and Notification Media - MediaPlayer
8. Location, Media and Notification Synchronous preparation:
Uri myUri = Uri.parse("android.resource://" + getPackageName() +
"/" + R.raw.myfile); MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDataSource(getApplicationContext(), myUri);
mediaPlayer.prepare(); mediaPlayer.start(); Aynchronous
preparation: Uri myUri = Uri.parse("http://path.to.remote/file");
MediaPlayer mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDataSource(getApplicationContext(), myUri);
mediaPlayer.prepareAsync(); mediaPlayer.setOnPreparedListener(new
OnPreparedListener() { @Override public void onPrepared(MediaPlayer
arg0) { mediaPlayer.start(); } }); Media - MediaPlayer
9. Location, Media and Notification For playback of video
content, there is a view that simplifies the management of the
states of MediaPlayer: the VideoView contains a SurfaceView for the
frame and a MediaPlayer. Like any other View, is part of a file or
xml layout is instantiated at runtime to add it to a ViewGroup.
VideoView videoView = new VideoView(this);
videoView.setVideoURI(Uri.parse("http://path.to.remote/file"));
videoView.setVideoPath("android.resource://" + getPackageName() +
"/" + R.raw.myfile); videoView.setOnPreparedListener(new
OnPreparedListener() { @Override public void onPrepared(MediaPlayer
mp) { mp.start(); } }); Media - VideoView
10. Location, Media and Notification A notification is a
message to the user out of the normal GUI application.
Notification
11. Location, Media and Notification There are 2 kind of
Notifications: Normal View: standard notification Big View:
expanded version Notification - Typology 1. Title 2. Large Icon 3.
Text 4. Info 5. Small Icon 6. Date
12. Location, Media and Notification You can create an
Notification object with NotificationCompat.Builder. The
Notification is then passed to NotificationManager. To create a
Notification You must specify:
NotificationCompat.Builder.setSmallIcon()
NotificationCompat.Builder.setTitle()
NotificationCompat.Builder.setContentText() The other methods are
optional. You need to specify the action to perform in case the
user clicksthe Notification with
NotificationCompat.Builder.setContentIntent() Notification -
Creation
13. Location, Media and Notification NotificationCompat.Builder
mBuilder = new NotificationCompat.Builder(
this).setSmallIcon(R.drawable.notification_icon)
.setContentTitle("My notification") .setContentText("Hello
World!"); // Creates an explicit intent for an Activity in your app
Intent resultIntent = new Intent(this, ResultActivity.class);
PendingIntent resultPendingIntent =
PendingIntent.getActivity(context, 0, resultIntent,
PendingIntent.FLAG_UPDATE_CURRENT);
mBuilder.setContentIntent(resultPendingIntent); NotificationManager
mNotificationManager = (NotificationManager)
getSystemService(Context.NOTIFICATION_SERVICE); // mId allows you
to update the notification later on.
mNotificationManager.notify(mId, mBuilder.build()); Notification -
Creation
14. Location, Media and Notification NotificationCompat.Builder
mBuilder = new NotificationCompat.Builder(
this).setSmallIcon(R.drawable.notification_icon)
.setContentTitle("Event tracker") .setContentText("Events
received"); NotificationCompat.InboxStyle inboxStyle = new
NotificationCompat.InboxStyle(); String[] events = new String[6];
// Sets a title for the Inbox style big view
inboxStyle.setBigContentTitle("Event tracker details:"); // Moves
events into the big view for (int i = 0; i < events.length; i++)
{ inboxStyle.addLine(events[i]); } // Moves the big view style
object into the notification object. mBuilder.setStyle(inBoxStyle);
Notification Big Style
15. Location, Media and Notification By Jelly Bean (Android
4.1), you can add actions to each notification. Notification
Actions This is possible using
NotificationCompat.Builder.addAction() method Intent intent = new
Intent(context, ExampleActivity.class); PendingIntent pendingIntent
= PendingIntent.getActivity(context, 0, intent,
Intent.FLAG_ACTIVITY_NEW_TASK);
mBuilder.addAction(R.drawable.ic_launcher, "Action 1",
pendingIntent);
16. Location, Media and Notification The GCM (Google Cloud
Messaging) is a service that allows you to communicate remotely to
the client of the key-value pairs data that can be displayed as a
notification to the user. The cliant can use these messages in
other ways. The implementation of GCM requires a server side as
well as the client. For the implementation of the client the Google
Play Services must be imported into the project as a library.
Notification GCM
17. Location, Media and Notification Notification GCM
Manifest
18. Location, Media and Notification Before performing any of
the GCM, it is necessary to verify that Google Play Services are
present on the device with the
GooglePlayServicesUtil.IsGooglePlayServicesAvailable() utility
class. If they are not present, the user must download them from
Google Play. A already pre-filled Dialog with everything you need
is available with the method
GooglePlayServicesUtil.getErrorDialog(). If Google Play Services
are available you can proceed with the flow that provides for the
registration on the Google server and then on the implementation of
the server side using a code called registrationId. Notification
GCM GPS check
19. Location, Media and Notification To try to register, you
must invoke the method GoogleCloudMessaging.register() in a Worker
Thread: GoogleCloudMessaging googleCloudMessaging =
GoogleCloudMessaging.getInstance(this); String registrationId =
googleCloudMessaging.register(SENDER_ID);
sendRegistrationIdToServer(); storeRegistrationId(); Notification
GCM Registration
20. Location, Media and Notification To receive, you need a
BroadcastReceiver whose implementation is limited to the
declaration of which service must handle the Intent and an
IntentService that handles the message: public class
GcmBroadcastReceiver extends WakefulBroadcastReceiver { @Override
public void onReceive(Context context, Intent intent) { //
Explicitly specify that GcmIntentService will handle the // intent.
ComponentName comp = new ComponentName(context.getPackageName(),
GcmIntentService.class.getName()); // Start the service, keeping
the device awake while it is // launching.
startWakefulService(context, (intent.setComponent(comp)));
setResultCode(Activity.RESULT_OK); } } Notification GCM
Receiving
21. Location, Media and Notification IntentService
Implementation example: public class GcmIntentService extends
IntentService { public GcmIntentService() {
super("GcmIntentService"); } @Override protected void
onHandleIntent(Intent intent) { Bundle extras = intent.getExtras();
if (!extras.isEmpty()) { // has effect of unparcelling Bundle
sendNotification(extras); } // Release the wake lock provided by
the WakefulBroadcastReceiver.
GcmBroadcastReceiver.completeWakefulIntent(intent); } }
Notification GCM Service
