I am working on an Android application in which I have to compare current time , with a time (saved) in a file, though everything is working fine. I have use services and in service i have use THREAD to run the service infinitely, and in addition to this i have also used PARTIAL_WAKE_LOCK to continue service even the device is sleep but the issue is that instead of acquiring PARTIAL_WAKE_LOCK my service runs for 1/2 hours and then again go to sleep. I don't want to acquire FULL_WAKE_LOCK. Is there any one who can guide me what i have to do in order to run this comparison, i.e. my service will run perfectly once the user set the time.
Thank you in advance.
You are doing it the wrong way. To create permanent service you must
declare it as foreground. No other way about it:
myService.startForeground(MY_NOTIFICATION_ID, my_notification);
If your interest with such a service is to periodically perform fast-ending
actions, and if the in between periods are long, you probably want to use
the alarm API and improve your app's battery consumption.
Edit:
To set a foreground service you must supply the system with a notification
object to be displayed at notification bar for as long as the service is in foreground
Why is that? Because foreground services cannot be killed, and Android needs to know
that the user is aware of that fact.
Setting as foreground:
static final int NOTIF_ID = 100;
// Create the FG service intent
Intent intent = new Intent(getApplicationContext(), MyActivity.class); // set notification activity
showTaskIntent.setAction(Intent.ACTION_MAIN);
showTaskIntent.addCategory(Intent.CATEGORY_LAUNCHER);
showTaskIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
PendingIntent pIntent = PendingIntent.getActivity(
getApplicationContext(),
0,
intent,
PendingIntent.FLAG_UPDATE_CURRENT);
Notification notif = new Notification.Builder(getApplicationContext())
.setContentTitle(getString(R.string.app_name))
.setContentText(contentText)
.setSmallIcon(R.drawable.ic_notification)
.setContentIntent(pIntent)
.build();
startForeground(NOTIF_ID, notif);
And reverting to 'stardard' service mode:
stopForeground(true).
Both setting to foreground and reverting to background can be called by either the service itself (e.g. its onCreate() method) or by external code (e.g. the activity that initiated the service). No problems here.
Related
I am using Firebase (FCM) to show Push Notifications to the user and I am running into a weird problem.
The code I have works for the following scenarios (using FirebaseMessagingService):
App in foreground - Receiving data in onReceive() and showing a popup inside app.
App in background - Receiving data in onReceive() and showing a notification for the user. If this is clicked the app will be brought back to front. The intent from this is received in LauncherActivity followed by a finish() call which takes me to whatever activity I already had open.
App completely closed - same as background. App will be started and intent will be handled in LauncherActivity before calling finish() on that.
And here is where it gets interesting:
App completely closed -> open it through notification (intent received in LauncherActivity) -> put the app in background and send another notification -> when this notification is clicked the LauncherActivity is completely ignored (onCreate is no longer called) and I get taken straight to whatever activity I already had. The intent here has no extras or categories.
Why is LauncherActivity being bypassed in this specific case? Keep in mind that this works fine if the app was initially started normally (not by clicking on a notification)
Intent mainIntent = getPackageManager().getLaunchIntentForPackage(getPackageName());
if (mainIntent != null) {
mainIntent.addCategory(NOTIFICATION_CATEGORY);
mainIntent.putExtra(.........);
}
PendingIntent pendingMainIntent = PendingIntent.getActivity(this, SERVICE_NOTIFICATION_ID, mainIntent, PendingIntent.FLAG_UPDATE_CURRENT);
NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(context, context.getString(R.string.default_notification_channel_id));
notificationBuilder.setContentIntent(pendingMainIntent);
//.....icon, color, pririty, autoCancel, setDefaults, setWhen, setShowWhen, contentText, setStyle
NotificationManager notificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
if (notificationManager != null) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel channel = new NotificationChannel(
getString(R.string.default_notification_channel_id),
getString(R.string.default_notification_channel),
NotificationManager.IMPORTANCE_HIGH
);
notificationManager.createNotificationChannel(channel);
notificationBuilder.setChannelId(getString(R.string.default_notification_channel_id));
}
notificationManager.notify(SERVICE_NOTIFICATION_ID, notificationBuilder.build());
}
I'd appreciate any ideas. Thank you.
When you launch an app for the first time, Android remembers the Intent that was used to launch it. Normally, when you launch an app from the HOME screen, this is an Intent that contains ACTION=MAIN and CATEGORY=LAUNCHER. If your app then goes to the background (for whatever reason), and the user later taps the icon on the HOME screen, the same launch Intent is used. Android matches this against the Intent used to launch the app for the first time, and if these match, Android doesn't launch a new Activity, it just brings the task containing the app from the background to the foreground in whatever state it was in when it got moved to the background. Under normal circumstances, this is exactly the behaviour that you want (and that the user expects).
However, when the app is launched for the first time from a Notification, this can mess things up. In your case, this is what you are seeing. You launch the app from a Notification and Android remembers the Intent used (from the Notification), when you later launch the app (again from a Notification), android matches the Intent in the Notification with the Intent used to launch the app for the first time, and thinks you want to bring the existing app task from the background to the foreground.
There are several ways to deal with this, depending on the behaviour that you want to have. The best thing to do is probably not to launch your root Activity (the one with ACTION=MAIN and CATEGORY=LAUNCHER) from the Notification. Instead launch a different Activity and have that Activity determine what it should do next (ie: redirect to the root Activity or something else, depending on the state of your app). You should also set the NO_HISTORY and EXCLUDE_FROM_RECENTS flags on the Intent that you put in the Notification. This will ensure that Android won't remember this Intent as the one that launched the app.
I build an application that manage a database of messages and show them to the user, i have a service that basically connect to web server and asks for updates.
I need that service to run every minute even if the application is closed.
so far i wrote the following code:
protected void registerAlarm() {
Intent getUpdatesService = new Intent(this, UpdatesService.class);
PendingIntent sender = PendingIntent.getBroadcast(this, 0, getUpdatesService, 0);
long firstTime = SystemClock.elapsedRealtime();
firstTime += 60 * 1000;
AlarmManager am = (AlarmManager)this.getSystemService(Context.ALARM_SERVICE);
am.setRepeating(AlarmManager.RTC_WAKEUP, firstTime, 60 * 1000, sender);
}
I call registerAlarm() from an activity that shows the messages.
That suppose to use AlarmManager to run the service evry minute but it doesn't work.
can anyone help me solve the problem?
I need that service to run every minute even if the application is closed.
That will not be practical on Android 6.0 and higher.
can anyone help me solve the problem?
Tactically, your problem is that you are using SystemClock.elapsedRealtime() and RTC_WAKEUP. Those do not match. Use ELAPSED_REALTIME_WAKEUP.
However:
Your app will not get control every minute on Android 6.0+, unless perhaps the user adds your app to the battery optimization whitelist in Settings
AlarmManager does not work at all in some environments, notably the current developer preview of Android apps on Chrome OS (though for all I know this is a bug)
You should use IntentService instead of Service because it automatically terminates after work is done plus it run on background thread
My Activityhosts 3 tabs and each tab is a Fragment.
I also have a Service which query a database perdiodically. Depending on the result of the query, I raise a Notification (from the Service).
When I click on the Notification, is it possible to launch a specific fragment? If yes, how can I do so?
Here is what I've done so far, in my Service class:
// When notification is clicked, go back to TabOperations Fragment
Intent i = new Intent(this, TabOperations.class);
PendingIntent pi = PendingIntent.getActivity(this, 0, i,PendingIntent.FLAG_UPDATE_CURRENT); // Give the phone access to the app
notification.setContentIntent(pi);
// Issue notification
NotificationManager nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
nm.notify(UNIQUE_ID, notification.build());
Of course, this does not work.
Any advice?
Instead of the Service sending a Notification, perhaps you would be better off with a different messaging system. For example, you can utilize the Observer pattern (or third-party libraries like EventBus) to send a message from the Service to the Activity that cares about such events. The activity can then use the event to start and attach the Fragment as necessary.
I'm learning how to make apps for android and I have started by creating one which makes my phone scream when its dropped.
I got it working to where the phone screams when dropped, but now I need to make it so that the phone screams when dropped even when the app is closed, and to show a notification in the notification bar saying that its running
What should I use to do this? Should I use intentService? Ive been looking all over and I'm not sure where to look. Any guides would be appreciated
You need to make your service run in the foreground. You can achieve this by showing a notification when your service is running.
This is how you need to make your service run as foreground
private void showNotification(String title)
{
NotificationCompat.Builder mBuilder =
new NotificationCompat.Builder(this)
.setSmallIcon(R.drawable.ic_launcher)
.setContentTitle(title);
startForeground(1000,mBuilder.build()); // 1000 - is Id for the notification
}
You can also set your custom RemoteViews in notification using setContent
You can remove the service from foreground state using stopForeground
check Service Training.
For your use case it's important that it's an foreground service:
Documentation Service
I need some suggestions for approaches to take...
Here's some background info:
Right now I have an Android app and a separate java program running on my server.
The java program continuously go out and gets information from different sites and stores them in 14 different entries in an SQL database on the server.
The Android app then queries the databases to retrieve the info to be displayed.
My goal:
I need suggestions on how to have the app handle checking for updates from the database, and then letting the user know that there is new information.
My first thought is that maybe I need to start a separate thread that queries the database for a time modified. Then if it finds updates, it would pop up on the screen that there is new information.
I'm not too well educated with the way threads or services work, so I guess I'm looking for how to implement this, or whether there is a completely different way to go about update checking that would be better.
Thanks in advance, I appreciate any feedback, input, or suggestions.
Hi Ryan I have also implemented a similar thing in my android app and surprisingly I also had 14 tables in my PostgreSQL Server. First of all, you would want to poll the server periodically even when the app is not in the foreground. For that you need to run a background Service - here you will have to manually create a thread in the service, because Service by default runs on the UI thread OR use an IntentService - you don't have to create a separate thread. Whatever code you write in the intent service will be handled in a different thread automatically
Now you have to make this service execute periodically. For that use an AlarmManager and use the setRepeating()function. In the arguments you have to give a PendingIntent to your Service or IntentService. But don't use an alarm manager if you are going to poll the server for every less than 1 minute. Because the battery will be wasted a lot.
Here is some code that might give you an idea :
function setalarm()
{
Intent intent = new Intent(getBaseContext(), Intent_Service.class);
PendingIntent sender = PendingIntent.getBroadcast(getBaseContext(), 192837, intent, PendingIntent.FLAG_UPDATE_CURRENT);
Random randomGenerator = new Random();
long interval=60000; //1 minute in milliseconds
AlarmManager am = (AlarmManager) getSystemService(ALARM_SERVICE);
am.setRepeating(AlarmManager.RTC, cal.getTimeInMillis(),interval,sender);
}
This is Intent_Service of type IntentService :
public class BackService extends IntentService
{
Context context=this;
//public Timer t=null;
public BackService()
{
super("myintentservice");
}
#Override
protected void onHandleIntent(Intent intent)
{
try
{
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "My Tag");
wl.acquire();
//..CPU will remain on during this section..
//make our network connections, poll the server and retrive updates
//Provide a notification if you want
wl.release();//Release the powerlock
}
}
}
But if you want instantaneous updates, then use Google Cloud Messaging Services. To know more about how it works see this
Hope this helps you.