I am starting to learn about the AlarmManager, and I want to fire a broadcast to fetch some info from a server. The documentation is clear about the intents and the alarms, but I cannot find anything on how the receiving end should look.
This is my alarm code:
AlarmManager aMgr = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, 0);
aMgr.setInexactRepeating(AlarmManager.ELAPSED_REALTIME,
SystemClock.elapsedRealtime() + 10000,
AlarmManager.INTERVAL_FIFTEEN_MINUTES, pendingIntent);
and my AlarmReceiver is like this:
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.d(MainActivity.TAG, "Received intent");
}
}
But nothing happens. I added a button to just fire the broadcast like this:
public void btnTrigger_onClick(View view) {
Intent i = new Intent(this, AlarmReceiver.class);
sendBroadcast(i);
}
and also nothing happens here.
I have used broadcasts before, but only with registerReceiver, but I do not want to process the broadcast in my Activity now.
Explicit broadcasts — ones where the Intent has the component name (i.e., class) — require a <receiver> element in the manifest in order to work.
Related
I want a task to do which require internet connection and it's must scheduled once in a day. I achieve above task partially using alarm manager like below.
Calendar c = Calendar.getInstance(); //gives u calendar with current time
c.add(Calendar.SECOND, 30);
AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(this, AlarmReceiver.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 1, intent, 0);
if (alarmManager != null) {
alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, c.getTimeInMillis(),
AlarmManager.INTERVAL_DAY, pendingIntent);
}
// my broadcast receiver
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
//my task will be here
// for now I planned to check internet here and if it has i'll continue the task
}
}
//in manifest
<receiver android:name=".broadcast_receiver.AlarmReceiver" />
Is there any way to postpone above task in same day whenever got internet connection?
Can AlarmManager be used to achieve above requirement?
You can achieve that with WorkManager. Check out the official docs for more info.
I'm making an app to remind the user of something. I want to show a notification at some time in the future. I've written the code below, following some tutorials, but it doesn't seem to work. At the time I expect the notification, it doesn't show up.
I'm using a BroadcastReceiver and the AlarmManager to make a notification at the desired time. Here's my (simplified) code.
Code to set the time:
try {
Date date = format.parse(timeInput);//This part works
long time = date.getTime();//Get the time in milliseconds
Intent i = new Intent(getBaseContext(), AlarmReceiver.class);
PendingIntent alarmSender = PendingIntent.getBroadcast(getBaseContext(), 0, i, 0);
AlarmManager am = (AlarmManager) getBaseContext().getSystemService(Context.ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP, time, alarmSender);
Toast.makeText(getBaseContext(), "Keep the app running to receive a reminder notification", Toast.LENGTH_LONG).show();
super.onBackPressed();
}catch(Exception e){
Toast.makeText(getBaseContext(), "Parsing error. Format:\ndd/MM/yyyy and HH:mm", Toast.LENGTH_SHORT).show();
}
The AlarmReceiver.onReceive() method:
#Override
public void onReceive(Context context, Intent intent) {
Intent i = new Intent(context, MenuActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, i, 0);
NotificationCompat.Builder nBulder = new NotificationCompat.Builder(context)
.setSmallIcon(R.drawable.notify_icon)
.setContentTitle("title")
.setContentText("text")
.setPriority(NotificationCompat.PRIORITY_DEFAULT)
.setContentIntent(pendingIntent)
.setAutoCancel(true);
NotificationManagerCompat nManager = NotificationManagerCompat.from(context);
nManager.notify(0, nBulder.build());
}
Everything is properly declared in the manifest file.
<receiver
android:name=".AlarmReceiver"
android:enabled="true"
android:exported="true"></receiver>
public class AlarmReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// TODO: This method is called when the BroadcastReceiver is receiving
// an Intent broadcast.
throw new UnsupportedOperationException("Not yet implemented");
}
}
Minor Changes:
try {
long time = System.currentTimeMillis();
Intent i = new Intent(getApplicationContext(), AlarmReceiver.class);
PendingIntent alarmSender = PendingIntent.getBroadcast(getApplicationContext(), 0, i, 0);
AlarmManager am = (AlarmManager) getApplication().getSystemService(Context.ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP, time, alarmSender);
} catch(Exception e){
Toast.makeText(getBaseContext(), "Parsing error. Format:\ndd/MM/yyyy and HH:mm", Toast.LENGTH_SHORT).show();
}
Difference between getContext() , getApplicationContext() , getBaseContext() and "this"
I've found another way to do it. Instead of using a BroadcastListener and the AlarmManager, I'm using a new Thread. It waits until System.currentTimeMillis() == time and runs a runnable on the UI thread using runOnUIThread(). In that runnable, a notification is made.
I don't know if this is a good/efficient solution, but it does the job fine.
I want a method to be executed when I press a button on my notification. For that purpose I am adding an action with a PendingIntent to my notification:
Intent intent = new Intent(context, AlertActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
Notification notification = new Notification.Builder(MainActivity.this)
.setContentTitle("New Notification")
.setContentText("Click Here")
.setSmallIcon(R.mipmap.ic_launcher)
.setContentIntent(pendingIntent)
.addAction(R.mipmap.ic_launcher, "Test2", pendingIntent)
.build();
notification.flags |= Notification.FLAG_AUTO_CANCEL;
NotificationManager manager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
manager.notify(0, notification);
That works, however I don't want to start an Activity when the user invokes the action. I just need to do some work.
For that purpose I implemented a Service which should be targeted by the PendingIntent instead:
public class MyServices extends IntentService {
public MyServices() {
super("MyServices");
}
#Override
protected void onHandleIntent(Intent intent) {
clearNotification();
}
public void clearNotification() {
NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
notificationManager.cancel(0);
Intent intent = new Intent(MyServices.this, MainActivity.class);
//Starting new activity just to check
startActivity(intent);
}
}
I create the PendingIntent like this:
final Intent intent = new Intent(context, MyServices.class);
final PendingIntent pendingIntent = PendingIntent.getService(context, 0, intent, 0);
However when I invoke the action on my notification nothing happens. What am I doing wrong?
A Notification is not part of your application. It is managed by the OS. It just so happens that there are APIs you can use to show/cancel/etc notifications.
A pending intent allows for external code (Notifications for example) to launch your app/activity/service/broadcastreceiver. This cannot be done without a pending intent.
What my task is to execute some piece of code when a specific action button is clicked, and clear notification; without starting any activity
You don't have to start an activity. You can do it in a broadcastreceiver that has no UI. Or, as CommonsWare suggested, use an IntentService, depending on what what you are doing in your "piece of code". IntentServices handle work in a separate thread.
I have a problem with receiving notification. I am sure it is sent as I see log for sending. But I never receive it as I never see log or notification. I am not quiet sure what I am doing wrong.
And I don't want repeating alarm.
Using Nexus 7 on Marshmallow.
PracticeWordsActivity.java
public void setAlarm(int day){
alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
alarmIntent = new Intent(PracticeWordsActivity.this,AlarmReceiver.class);
pendingIntent = PendingIntent.getBroadcast(this, 0, alarmIntent, 0);
//alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, System.currentTimeMillis()+15000, pendingIntent);
alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime()+15000, pendingIntent);
Log.e(TAG,"Lift off");
}
AlarmService
public class AlarmService extends IntentService
{
private static final int NOTIFICATION_ID = 1;
private static final String TAG = "AlarmService";
private NotificationManager notificationManager;
private PendingIntent pendingIntent;
public AlarmService() {
super("AlarmService");
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return super.onStartCommand(intent,flags,startId);
}
#Override
protected void onHandleIntent(Intent intent) {
Log.e(TAG,"Alarm Service has started.");
Context context = this.getApplicationContext();
notificationManager =
(NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
Intent mIntent = new Intent(this,MainActivity.class);
Bundle bundle = new Bundle();
bundle.putString("test", "test");
mIntent.putExtras(bundle);
pendingIntent = PendingIntent.getActivity(context, 0, mIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Resources res = this.getResources();
NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
builder.setContentIntent(pendingIntent)
.setSmallIcon(R.drawable.ic_launcher)
.setLargeIcon(BitmapFactory.decodeResource(res, R.drawable.ic_launcher))
.setTicker("TITLE")
.setAutoCancel(true)
.setContentTitle("TITLE2")
.setContentText("SUBJECT");
notificationManager =(NotificationManager)getSystemService(NOTIFICATION_SERVICE);
notificationManager.notify(NOTIFICATION_ID, builder.build());
Log.e(TAG,"Notifications sent.");
}
AlarmReceiver.java
public class AlarmReceiver extends WakefulBroadcastReceiver {
private static final String TAG = "AlarmReceiver";
Intent intent;
PendingIntent pendingIntent;
NotificationManager notificationManager;
#Override
public void onReceive(Context context, Intent intent) {
Log.e(TAG, "BroadcastReceiver has received alarm intent.");
Intent service1 = new Intent(context, AlarmService.class);
context.startService(service1);
}
}
AndroidManifest.xml
I have set receiver and service after declaring last activity in AndroidManifest.
...
</activity>
<receiver android:name=".AlarmReceiver"
android:enabled="true"/>
<service android:name=".AlarmService" />
</application>
You're using AlarmManager.ELAPSED_REALTIME_WAKEUP to set the alarm. ELAPSED_REALTIME_WAKEUP means time elapsed since the device booted up.
If you want the alarm to be triggered 15 seconds after you set it, use:
alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime()+15000, pendingIntent);
or
alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()+15000, pendingIntent);
Also, I see you're triggering the alarm in WAKEUP mode and in your broadcast receiver you're starting a service. There is a chance that the device will go back to sleep before the service gets started. You can use WakefulBroadcastReceiver to prevent that.
You don't need to worry about repeating alarms, if you use the same intent to set a new alarm, the previous alarm that is using the same intent will be canceled.
I've been trying to setup my first alarm using AlarmManager and BroadCastReceiver as explained here: http://smartandroidians.blogspot.com.es/2010/04/alarmmanager-and-notification-in.html
My setup:
AndroidManifest.xml:
<receiver android:name="es.radiopodcastellano.player.SleepAlarm" />
My main Activity onCreate (this code actually resides on a subclass, but to simplify I put it there):
#Override
public void onCreate(Bundle savedInstanceState) {
// <Stripped code>
AlarmManager alarm = (AlarmManager) currentContext.getSystemService(Context.ALARM_SERVICE);
Intent intent = new Intent(this.getApplicationContext(), SleepAlarm.class);
PendingIntent pendingIntent = PendingIntent.getBroadcast(this.getApplicationContext(), 0, intent, PendingIntent.FLAG_ONE_SHOT);
alarm.set(AlarmManager.RTC_WAKEUP,(System.currentTimeMillis() + (5 * 1000)),pendingIntent);
}
SleepAlarm.java:
public class SleepAlarm extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
Log.d("RPod_SleepAlarm","Alarm!!");
}
}
Output from "adb shell dumpsys alarm" show this, so it seems the intent is being called:
es.radiopodcastellano.player
221ms running, 32 wakeups
44 alarms: flg=0x4 cmp=es.radiopodcastellano.player/.SleepAlarm
However, Logcat shows nothing for "RPod_SleepAlarm" tag. What could I be doing wrong?
I found the problem.
The receiver on the manifest was inside another receiver for a widget, and it must be a children of the application. So, if you're having the same behaviour as me, please check that you've set up the AndroidManifest.xml correctly: