Hi guys. I've been trying to make notifications for my calendar-planner project and I'm stuck for the past couple of days on an issue with no progress.
Thus far I have a notification publisher that works fine as long as the app is isn't removed from the recent tasks. Otherwise, the notifications will not be shown.
I tried searching online for answers but got no concrete answer for how it is supposed to work. What I did find simply doesn't work. The code:
Declaring the service in the manifest-
NotificationService (The class that's supposed to handle the notifications)-
I want to stress - the notifications properly work when the app is in the background\foreground.
I don't have prior knowledge with processes. From what I gathered the problem is that this app component is destroyed when the app itself is destroyed.
One work around I found was making it a foreground service, however this doesn't suit the nature of the app. The other is making onStartCommand() return START_REDELIEVER_INTENT, I thought it made sense according to the docs, but it does nothing. Some people suggested START_STICKY is the key but it didn't work either.
I hope I descirbed the issue well enough and gave the relevant code. Any insight into the matter would be appreciated.
Also, any good sources that explain this subject. Pehaps I overlooked something obvious or simply didn't manage to peice things together.
Thus far I have a notification publisher that works fine as long as the app is isn't removed from the recent tasks. Otherwise, the notifications will not be shown.
I tried searching online for answers but got no concrete answer for how it is supposed to work. What I did find simply doesn't work. The code:
Declaring the service in the manifest-
Code:
<service android:name=".Helpers.NotificationService"
android:exported="false" />
Code:
package com.example.android.calendar.Helpers;
import android.app.AlarmManager;
import android.app.IntentService;
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.NotificationCompat;
import android.support.v4.app.NotificationManagerCompat;
import com.example.android.calendar.Model.Event;
import com.example.android.calendar.R;
import java.util.Calendar;
import java.util.HashMap;
import java.util.UUID;
public class NotificationService extends IntentService {
private static Context mContext;
private static final String NOTIFICATION_CHANNEL_ID = "notificationChannelId";
private static final String NOTIFICATION_CHANNEL_NAME = "eventsNotificationChannel";
public static final String EX_ID = "extraId";
public static final String ACTION_START_SERVICE = "startService";
public static final String ACTION_NOTIFY_ON_TIME = "notifyOnTime";
private static HashMap<UUID, Notification> notifications = new HashMap<>();
public static int mCounter = 0;
public NotificationService(){
super("notificationService");
}
@Override
public void onCreate(){
super.onCreate();
}
@Override
protected void onHandleIntent(Intent intent){
if(intent.getAction().contentEquals(ACTION_START_SERVICE))
return;
UUID id = (UUID) intent.getSerializableExtra(EX_ID);
Notification notification = notifications.get(id);
NotificationManagerCompat mNM = NotificationManagerCompat.from(mContext);
mNM.notify(mCounter++, notification);
try{
Thread.sleep(1000);
} catch(InterruptedException e){
e.printStackTrace();
}
}
@Override
public int onStartCommand(Intent intent, int flags, int startId){
super.onStartCommand(intent, flags, startId);
return IntentService.START_REDELIEVER_INTENT;
}
public void createNotificationChannel(Context context){
mContext = context;
NotificationManager mNM = (NotificationManager) mContext.getSystemService(NOTIFICATION_SERVICE);
NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID,
NOTIFICATION_CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
notificationChannel.enableVibration(true);
notificationChannel.setVibrationPattern(new long[]{100, 200, 300, 400, 500, 400, 300, 200, 100});
notificationChannel.enableLights(true);
mNM.createNotificationChannel(notificationChannel);
}
public void createNotification(int minutesBefore, Event event){
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(mContext, NOTIFICATION_CHANNEL_ID).
setSmallIcon(R.drawable.ic_launcher_foreground).setContentTitle(event.getLabel()).
setContentText(event.getComment()).setAutoCancel(true);
// If an event is edited, remove existing notification
if(notifications.get(event.getId()) != null)
notifications.remove(event.getId());
Calendar mCalendar = Calendar.getInstance();
notifications.put(event.getId(), mBuilder.build());
mCalendar.setTime(event.getTime());
mCalendar.set(Calendar.SECOND, 0);
Intent intent = new Intent(mContext, NotificationService.class);
intent.putExtra(EX_ID, event.getId());
intent.setAction(ACTION_NOTIFY_ON_TIME);
PendingIntent notificationIntent = PendingIntent.getService(mContext, (int)System.currentTimeMillis(),
intent, PendingIntent.FLAG_CANCEL_CURRENT);
long triggerInMills = mCalendar.getTimeInMillis() - Calendar.getInstance().getTimeInMillis();
AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
alarmManager.setExact(AlarmManager.RTC, System.currentTimeMillis() + triggerInMills, notificationIntent);
}
public void cancelNotification(Event event, PendingIntent notificationIntent){
AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
alarmManager.cancel(notificationIntent);
notifications.remove(event.getId());
}
}
I want to stress - the notifications properly work when the app is in the background\foreground.
I don't have prior knowledge with processes. From what I gathered the problem is that this app component is destroyed when the app itself is destroyed.
One work around I found was making it a foreground service, however this doesn't suit the nature of the app. The other is making onStartCommand() return START_REDELIEVER_INTENT, I thought it made sense according to the docs, but it does nothing. Some people suggested START_STICKY is the key but it didn't work either.
I hope I descirbed the issue well enough and gave the relevant code. Any insight into the matter would be appreciated.
Also, any good sources that explain this subject. Pehaps I overlooked something obvious or simply didn't manage to peice things together.