i have a service which shows a toast message. i defined it in manifest like this-
<service android:name=".ShowNotification" />
and this is my service-
public class ShowNotification extends Service {
#Override
public void onCreate() {
super.onCreate();
Toast.makeText(getBaseContext(), "service worked once",
Toast.LENGTH_LONG).show();
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}
but i cannot figure out how to stop this service and also how to start it again?
Try :
stopService(new Intent(this, ShowNotification.class));
startService(new Intent(this, ShowNotification.class));
And restart the Service, gona recall onCreate()
Use IntentService rather than using only Service. IntentService will be destroyed automatically after completion of the task.You don't need to worry about stopping it.
I am implementing in my Android app a splash screen which:
dowloads a sqlite database from a server
loads urls to get JSONs
creates a sqlite database in the device and execute several queries
I am using AsyncTask to do everything, my problem will occur if the user close the app in the middle of the process or turn off the device because the app:
could be creating a database or executing crucial queries in the device
could be downloading the sqlite db from a server
could be running several important process
etc
Definitely, the entire process (3-5 seconds) is important.
So... How could I avoid this? should I use handlers, loaders, on-(pause, stop, destroy) methods in order to get my objective? Can you give me an example?
As mentioned in the comment above, you should use a service as their lifecycle is separate to that of the activity.
Create the service like so:
public class MyService extends Service {
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Do everything you need to here, then call stop:
Log.d("DEBUG", "Started...");
stopSelf();
return super.onStartCommand(intent, flags, startId);
}
#Override
public void onDestroy() {
Intent intent = new Intent("com.example.androidexample.SERVICE_STOPPING");
sendBroadcast(intent);
super.onDestroy();
}
}
Then in the activity:
public class MainActivity extends Activity {
private ServiceCompleteReceiver receiver;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
IntentFilter filter;
receiver = new ServiceCompleteReceiver();
filter = new IntentFilter("com.example.androidexample.SERVICE_STOPPING");
startService(new Intent(this, MyService.class));
registerReceiver(receiver, filter);
}
public class ServiceCompleteReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// Do whatever needs to be done here
unregisterReceiver(receiver);
}
}
}
EDIT :
Don't forget to add it to your manifest as well
<service
android:name="com.example.androidexample.MyService"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
</service>
I want that this service run even if the application is closed (kiiled) or even if the user dont start the app.
i want the service start after the application is installed and from this point, the service should run always.
public class notifications extends Service {
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onCreate() {
}
#Override
public void onStart(Intent intent, int startId) {
final Handler handler = new Handler();
final Runnable runb = new Runnable()
{
public void run()
{
Toast.makeText(getApplicationContext(), " Service Started", Toast.LENGTH_LONG).show();
handler.postDelayed(this, 10000);
}
};
handler.postDelayed(runb, 0);
}
#Override
public void onDestroy() {
}
}*/
public class notifications extends IntentService
{
private Timer mBackGroundTimer;
public notifications()
{
super("myservice");
this.mBackGroundTimer=new Timer();
}
#Override
protected void onHandleIntent(Intent intent)
{
// TODO Auto-generated method stub
mBackGroundTimer.schedule(new TimerTask()
{
public void run()
{
try
{
Notification("This is message from Dipak Keshariya (Android Application Developer)", "This is Android Notification Message");
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
},1000, 2000);
} // END onHandleIntent()
private void mStopTimer()
{
//Call this whenever you need to stop the service
mBackGroundTimer.cancel();
}
private void Notification(String notificationTitle, String notificationMessage) {
NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
android.app.Notification notification = new android.app.Notification(R.drawable.ic_launcher, "A New Message from Dipak Keshariya (Android Developer)!",
System.currentTimeMillis());
Intent notificationIntent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
notification.setLatestEventInfo(getApplicationContext(), notificationTitle, notificationMessage, pendingIntent);
notificationManager.notify(10001, notification);
}
}
how i can do that?
Looking at your code, it appears you want your service to periodically give notifications.
As far as having it run continuously goes, keep in mind that by design, the Android system may terminate your service process at any time. You can influence this a bit, but you cannot prevent the system from killing your service.
So for your periodical actions, it would be best to use AlarmManager with a recurring alarm. Your service would then basically be one-shot, i.e. perform the action once and then exit.
For some code, look here for example:
Android: Alarm Manager
You need to implement the OnStartCommand method of the Service class and in it, return Service.START_STICKY. That will do the trick. If you kill the application, the service will continue to run in the background. However, if you restart your phone, I think you need to implement something else in your app, as well, a boot service or something like that.
As you requirement is to run the service in the background. you are on the right track to use the service because this is meant for background running purpose only.
from the activitiy you can start the service by
startService(new Intent(activityName.this, serviceName.class));
or if your application is not having any activity then you can make the service as default and main launcher of the application by putting
<service android:name="name of the service" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</service>
I think answer to this question is this : https://developer.android.com/training/sync-adapters/creating-sync-adapter.html
Sync Adapters introduced in Google I/O 2013.
I'm trying to call a service class to update the value of a variable from my widget but it doesn't ever seem to get to the service class. I've had a look at some examples and I can't figure out what I'm doing wrong, and I don't really know very much about services yet. All help appreciated.
Service class
public class toggleMonitoringService extends Service{
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onCreate()
{
Log.d("Me","creating service");
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int startId, int something) {
// TODO Auto-generated method stub
String toggle = intent.getExtras().getString("Toggle");
Log.d("Me","Toggle : " + toggle);
if (toggle.equals("app1"))
{
UpdateWidgetService.monitorApp1 = !UpdateWidgetService.monitorApp1;
}
else if (toggle.equals("app2"))
{
UpdateWidgetService.monitorApp2 = !UpdateWidgetService.monitorApp2;
}
super.onStartCommand(intent, startId, something);
return 0;
}
}
Where I set up the intent and pending intent to handle the button click from the widget
Intent monitor1toggle = new Intent(this.getApplicationContext(),toggleMonitoringService.class);
monitor1toggle.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
monitor1toggle.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS,allWidgetIds);
monitor1toggle.putExtra("Toggle","app1");
PendingIntent monitor1 = PendingIntent.getService(getApplicationContext(), 0 , monitor1toggle,0);
remoteViews.setOnClickPendingIntent(R.id.firstappstatus, monitor1);
Try start service manually, wihtout using PendingIntent.
Better way is not to start service each time you need to do something, but to start it once, bind to it and use common method calls when you need something from the service.
For your example even a simple Thread would be more appropriate.
I am using Service in my application and it needs to run until my application is uninstalled, but the problem is it gets killed by OS.
How can we prevent it from being killed by OS? Or if it gets killed can we restart that service again through programmatically?
You may run the service in the foreground using startForeground().
A foreground service is a service that's considered to be something
the user is actively aware of and thus not a candidate for the system
to kill when low on memory.
But bear in mind that a foreground service must provide a notification for the status bar (read here), and that the notification cannot be dismissed unless the service is either stopped or removed from the foreground.
Note: This still does not absolutely guarantee that the service won't be killed under extremely low memory conditions. It only makes it less likely to be killed.
I've been puzzled by the same issue to yours recently.but now,I've found a good solution.
First of all,you should know that, even your service was killed by OS, the onCreate method of your service would be invoked by OS in a short while.So you can do someting with the onCreate method like this:
#Override
public void onCreate() {
Log.d(LOGTAG, "NotificationService.onCreate()...");
//start this service from another class
ServiceManager.startService();
}
#Override
public void onStart(Intent intent, int startId) {
Log.d(LOGTAG, "onStart()...");
//some code of your service starting,such as establish a connection,create a TimerTask or something else
}
the content of "ServiceManager.startService()" is:
public static void startService() {
Log.i(LOGTAG, "ServiceManager.startSerivce()...");
Intent intent = new Intent(NotificationService.class.getName());
context.startService(intent);
}
However, this solution is just available for the situation of your service being killed by GC.Sometimes our service might be killed by user with Programme Manager.In this situation,your prosses will be killed,and your service will never been re-instantiated.So your service can not be restarted.
But the good news is,when the PM kill your service,it will call your onDestroy method.So we can do something with that method.
#Override
public void onDestroy() {
Intent in = new Intent();
in.setAction("YouWillNeverKillMe");
sendBroadcast(in);
Log.d(LOGTAG, "onDestroy()...");
}
The string of "YouWillNeverKillMe" is a custom action.
The most important thing of this method is,don't add any code before send the broadcast.As system will not wait for completion of onDestroy(),you must send out the broadcast as soon as posible.
Then regist a receiver in manifast.xml:
<receiver android:name=".app.ServiceDestroyReceiver" >
<intent-filter>
<action android:name="YouWillNeverKillMe" >
</action>
</intent-filter>
</receiver>
Finally,create a BroadcastReceiver,and start your service in the onReceive method:
#Override
public void onReceive(Context context, Intent intent) {
Log.d(LOGTAG, "ServeiceDestroy onReceive...");
Log.d(LOGTAG, "action:" + intent.getAction());
Log.d(LOGTAG, "ServeiceDestroy auto start service...");
ServiceManager.startService();
}
Hope this will be helpful to you,and excuse my poor written english.
Override method onStartCommand() in your service class and simply return START_STICKY (as suggested by "Its not blank"). That's all you need. If the process that runs your service gets killed (by a low memory condition for example), the Android system will restart it automatically (usually with some delay, like 5 seconds).
Don't use onStart() anymore as suggested in another answer, it's deprecated.
use
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
//**Your code **
// We want this service to continue running until it is explicitly
// stopped, so return sticky.
return START_STICKY;
}
ref Documentation lifecycle of Service.
Edit added method.
As far i know, onDestroy() will be called only when the service is explicitly stopped(Force Stop). But this method won't get called in case the service gets killed by OS/swiping the Recent Apps list. In those cases another event handler named onTaskRemoved(Intent) gets called. This is due to a defect in Android 4.3-4.4 as per the link here. Try using the below code:-
public void onTaskRemoved(Intent intent){
super.onTaskRemoved(intent);
Intent intent=new Intent(this,this.getClass());
startService(intent);
}
I found another solution of the problem which gurantees that your service will be always alive. In my case, this scheme resloves also the problem with FileObserver, which stops work after some period of time.
Use an activity (StartServicesActivity) to start the service (FileObserverService) as Foreground service.
Use BroadcastReceiver class (in example CommonReceiver) to restart your service in some special situations and in case it was killed.
I used this code in my app "Email Pictures Automatically"
https://play.google.com/store/apps/details?id=com.alexpap.EmailPicturesFree
Here is CommonReceiver class.
public class CommonReceiver extends BroadcastReceiver {
public void onReceive(Context paramContext, Intent paramIntent)
{
paramContext.startService(new Intent(paramContext, FileObserverService.class));
}
}
Here is its definition in AndroidManifest.xml just before application closing tag.
<receiver android:name="com.alexpap.services.CommonReceiver">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED"/>
</intent-filter>
<intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.USER_PRESENT"/>
</intent-filter>
</receiver>
Start service in StartServicesActivity activity.
Intent iFileObserver = new Intent(StartServicesActivity.this, FileObserverService.class);
StartServicesActivity.this.startService(iFileObserver);
Here is onStartCommand() method of the service.
public int onStartCommand(Intent intent, int flags, int startId) {
int res = super.onStartCommand(intent, flags, startId);
/*** Put your code here ***/
startServiceForeground(intent, flags, startId);
return Service.START_STICKY;
}
public int startServiceForeground(Intent intent, int flags, int startId) {
Intent notificationIntent = new Intent(this, StartServicesActivity.class);
notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
Notification notification = new NotificationCompat.Builder(this)
.setContentTitle("File Observer Service")
.setContentIntent(pendingIntent)
.setOngoing(true)
.build();
startForeground(300, notification);
return START_STICKY;
}
I tested this code using Task Killer app, and each time the service was killed, it was restarted again almost immediately (performs onStartCommand()). It is restarted also each time you turn on the phone and after rebooting.
I use this code in my application, which emails every picture you take with your phone to predefinde list of emails. The sending email and list of receiving emails are set in another activity and are stored in Shared Preferences. I took about 100 pictures in several hours and all they were sent properly to receiving emails.
#Override
public void onDestroy() {
super.onDestroy();
startService(new Intent(this, YourService.class));
}
write above code in your service and your service will never stop even user want to destroy it or they want to kill it it will never kill untill your app not get uninstall from your device
You can try to start your service repeatedly, for example every 5 sec.
This way, when your service is running, it will perform onStartCommand() every 5 sec. I tested this scheme and it is very reliable, but unfortunately it increases slightly phone overhead.
Here is the code in your activity where you start the service.
Intent iFileObserver = new Intent(StartServicesActivity.this, FileObserverService.class);
PendingIntent pendingIntentFileObserver = PendingIntent.getService(StartServicesActivity.this, 0, iFileObserver, 0);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
Date now = new Date();
//start every 5 seconds
alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, now.getTime(), 5*1000, pendingIntentFileObserver);
And here is onStartCommand() of the service.
//class variable
public static boolean isStarted = false;
public int onStartCommand(Intent intent, int flags, int startId) {
int res = super.onStartCommand(intent, flags, startId);
//check if your service is already started
if (isStarted){ //yes - do nothing
return Service.START_STICKY;
} else { //no
isStarted = true;
}
/**** the rest of your code ***/
return Service.START_STICKY;
}
First create service in another process, and write broadcaster which runs in recursion in time intervals
protected CountDownTimer rebootService = new CountDownTimer(9000, 9000) {
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
sendBroadcast(reboot);
this.start();
Log.d(TAG, "rebootService sending PREVENT AUTOREBOT broadcast");
}
};
After that register broadcast receiver in main process also with timer recursion that is launched after first broadcast from service arrived
protected static class ServiceAutoRebooter extends BroadcastReceiver {
private static ServiceAutoRebooter instance = null;
private RebootTimer rebootTimer = null;
private static ServiceAutoRebooter getInstance() {
if (instance == null) {
instance = new ServiceAutoRebooter();
}
return instance;
}
public class RebootTimer extends CountDownTimer {
private Context _context;
private Intent _service;
public RebootTimer(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onTick(long millisUntilFinished) {
}
#Override
public void onFinish() {
_context.startService(_service);
this.cancel();
Log.d(TAG, "Service AutoRebooted");
}
}
#Override
public void onReceive(Context context, Intent intent) {
if (rebootTimer == null) {
Log.d(TAG, "rebootTimer == null");
rebootTimer = new RebootTimer(10000, 10000);
rebootTimer._context = context;
Intent service = new Intent(context, SomeService.class);
rebootTimer._service = service;
rebootTimer.start();
} else {
rebootTimer.cancel();
rebootTimer.start();
Log.d(TAG, "rebootTimer is restarted");
}
}
}
Service will be auto-rebooted if time at RebootTimer (main process) expires, which means that "PREVENT AUTOREBOT" broadcast from service hasn't arrived
i found a solution .... late answer but i wanted to answer...
we can send a broadcast in the ondestroy of the service and create a receiver that receives the broadcast and starts the service again.... when it is destroyed by any reasons...
pls try following:
final Messenger mMessenger = new Messenger(new IncomingHandler());
class IncomingHandler extends Handler {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
default:
super.handleMessage(msg);
}
}
}
#Override
public void onCreate() {
super.onCreate();
makeServiceForeground();
}
#Override
public IBinder onBind(Intent arg0) {
return mMessenger.getBinder();
}
private void makeServiceForeground() {
IActivityManager am = ActivityManagerNative.getDefault();
try {
am.setProcessForeground(onBind(null), android.os.Process.myPid(), true);
} catch (RemoteException e) {
Log.e("", "cant set to foreground" + e.toString());
}
}
also need add in manifest.xml
<uses-permission android:name="android.permission.SET_PROCESS_LIMIT"/>