Null error when I try to notify something

Question

Hi guys I'm at the beginning with Android and I'm trying to make a notify from a class different from my main activity. But e.printStackTrace() say "null" and it stop at line : "NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);" If I make the same notification from the mainActivity all goes well. Can you help me please?

if(giorni_di_differenza <= 15)
{

    try{
        PendingIntent pi = PendingIntent.getActivity(context, 0, new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS), 0);
        NotificationCompat.Builder n = new NotificationCompat.Builder(context)
            .setContentTitle(nome_evento)
            .setContentText(descrizione_evento)
            .setContentIntent(pi)
            .setAutoCancel(true)
            .setLights(Color.GREEN, 1000, 1000)
            .setSmallIcon(R.drawable.ic_launcher);

        NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);

        notificationManager.notify(0, n.build());

    }catch(Exception e){
        e.printStackTrace();
    }
}

If you need more code I can send you.

LogCat: http://pastebin.com/W4hKbf6W (the Pause GC error is an error due to Samsung stock ROM)

ok, one second @kalyanpvs

Pierpaolo Ercoli
– Pierpaolo Ercoli

2014-10-31 11:14:26 +00:00
Commented Oct 31, 2014 at 11:14 — Pierpaolo Ercoli
– Pierpaolo Ercoli, Commented Oct 31, 2014 at 11:14

M D · Accepted Answer · 2014-10-31 11:16:18Z

3

you need Context for accessing NotificationManager from Outside Activity

    NotificationManager notificationManager = (NotificationManager) context.getSystemService(NOTIFICATION_SERVICE);

and also your logcat clearly said

java.lang.IllegalStateException: System services not available to Activities before onCreate()

You can access NotificationManager only after onCreate() of Activity

answered Oct 31, 2014 at 11:16

M D

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5 Comments

Pierpaolo Ercoli Over a year ago

it works, but, when the debug stop, the notification disappear :0

Pierpaolo Ercoli Over a year ago

it works ok, the problem was that I did two notifications, and so...how can I do all two ? @MD

M D Over a year ago

@PierpaoloErcoli I did not get it. What are you talk in about?

Pierpaolo Ercoli Over a year ago

if I call two different notifications, for example one to notify that GPS is turned off, and another that notify anything else. My app notify the second.

M D Over a year ago

@PierpaoloErcoli For that you'll have to change NotificationID at notificationManager.notify(0, n.build()); as 0 to 1

Hamad · Accepted Answer · 2014-10-31 11:40:44Z

2

ya because it doesn't find context in your class:

NotificationManager nm = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

do it like this:

or

//pass different id for different notifications
private void showNotification(Context con, int notificationID) {
    if(giorni_di_differenza <= 15)
    {

        try{
            PendingIntent pi = PendingIntent.getActivity(con, 0, new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS), 0);
            NotificationCompat.Builder n = new NotificationCompat.Builder(con)
                .setContentTitle(nome_evento)
                .setContentText(descrizione_evento)
                .setContentIntent(pi)
                .setAutoCancel(true)
                .setLights(Color.GREEN, 1000, 1000)
                .setSmallIcon(R.drawable.ic_launcher);
        NotificationManager notificationManager = (NotificationManager) con.getSystemService(NOTIFICATION_SERVICE);

        notificationManager.notify(notificationID, n.build());

    }catch(Exception e){
        e.printStackTrace();
    }
}
}

edited Oct 31, 2014 at 11:40

answered Oct 31, 2014 at 11:19

Hamad

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3 Comments

Pierpaolo Ercoli Over a year ago

it works ok, the problem was that I did two notifications, and so...how can I do all two ? @Hamad

Hamad Over a year ago

change this: notificationManager.notify(0, n.build()); to this notificationManager.notify(1, n.build());

Pierpaolo Ercoli Over a year ago

wait I have another problem

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