Creating Android Notification every 15 minutes

Question

Hello I have a project in uni and I need to add notification to my application. Here's the code for the creation and starting the notification. Everything compile good however it does not display any notifications. Alarm reciever -

package com.example.alex.daily_horoscope;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.NotificationCompat;

public class AlarmReceiver extends BroadcastReceiver {
public AlarmReceiver() {
}

@Override
public void onReceive(Context context, Intent intent) {
// fire notification

    // Gets an instance of the NotificationManager service
    final NotificationManager mgr = (NotificationManager)     context.getSystemService(Context.NOTIFICATION_SERVICE);
    NotificationCompat.Builder mBuilder =
            new NotificationCompat.Builder(context)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(context.getResources().getText(R.string.notification))
                    .setContentText("You have new horoscope");
    // This pending intent will open after notification click
    Intent resultIntent = new Intent(context, MainActivity.class);
    PendingIntent resultPendingIntent =
            PendingIntent.getActivity(context, 0, resultIntent,PendingIntent.FLAG_UPDATE_CURRENT);

    mBuilder.setContentIntent(resultPendingIntent);
    mBuilder.setAutoCancel(true);
    // Sets an ID for the notification
    int mNotificationId = 001;
    // Builds the notification and issues it.
    mgr.notify(mNotificationId, mBuilder.build());
}
}

Service starter

package com.example.alex.daily_horoscope;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.SystemClock;

public class ServiceStarter extends BroadcastReceiver {
public final static int ALARM_ID = 12345;

@Override
public void onReceive(Context context, Intent intent) {
    System.out.println("Start service");
    if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED")) {
        System.out.println("Boot completed");
        // start the alarm on phone reboot
        Intent intentAlarm = new Intent(context, AlarmReceiver.class);
        System.out.println("calling Alarm receiver ");
        AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
        //set the notification to repeat every fifteen minutes
        long startTime = 1*60*1000; // 2 min
        // set unique id to the pending item, so we can call it when needed
        PendingIntent pi = PendingIntent.getBroadcast(context, ALARM_ID, intentAlarm, PendingIntent.FLAG_UPDATE_CURRENT);
        alarmManager.setInexactRepeating(AlarmManager.RTC, SystemClock.elapsedRealtime() +
                startTime, AlarmManager.INTERVAL_FIFTEEN_MINUTES, pi);

    }

}

}

Answer 1

in your main activity put this:

    Intent intentAlarm = new Intent(context, AlarmReceiver.class);
    System.out.println("calling Alarm receiver ");
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    //set the notification to repeat every fifteen minutes
    long startTime = 2*60*1000; // time interval in ms, 2 min in this case
    // set unique id to the pending item, so we can call it when needed
    PendingIntent pi = PendingIntent.getBroadcast(context, ALARM_ID, intentAlarm, PendingIntent.FLAG_UPDATE_CURRENT);
    alarmManager.setInexactRepeating(AlarmManager.RTC, SystemClock.elapsedRealtime() +
            startTime, AlarmManager.INTERVAL_FIFTEEN_MINUTES, pi);

Answer 2

This code will show you a notification in every 1 minute interval.

Replace your AlarmReceiver class with this -

public class AlarmReceiver extends BroadcastReceiver {
    int mNotificationId = 001;
    public AlarmReceiver() {
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        Toast.makeText(context, "AlarmReceiver", Toast.LENGTH_LONG).show();
        // Gets an instance of the NotificationManager service
        final NotificationManager mgr = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

        NotificationCompat.Builder mBuilder =   new NotificationCompat.Builder(context);

                mBuilder.setSmallIcon(R.mipmap.ic_launcher) // notification icon
                        .setContentTitle(context.getResources().getText(R.string.notification))
                        .setContentText("You have new horoscope")
                        .setAutoCancel(true); // clear notification after click

        Intent resultIntent = new Intent(context, MainActivity.class);
        PendingIntent resultPendingIntent =
                PendingIntent.getActivity(context, mNotificationId, resultIntent,PendingIntent.FLAG_UPDATE_CURRENT);

        mBuilder.setContentIntent(resultPendingIntent);
        NotificationManager mNotificationManager =
                (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
        mNotificationManager.notify(mNotificationId, mBuilder.build());
    }
}

Add this activity as launcher activity -

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    Intent intentAlarm = new Intent(this, AlarmReceiver.class);
    System.out.println("calling Alarm receiver ");
    AlarmManager alarmManager = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
    //set the notification to repeat every fifteen minutes
    long startTime = 1*60*1000; // 2 min
    // set unique id to the pending item, so we can call it when needed
    PendingIntent pi = PendingIntent.getBroadcast(this, ALARM_ID, intentAlarm, PendingIntent.FLAG_UPDATE_CURRENT);
    alarmManager.setInexactRepeating(AlarmManager.RTC, SystemClock.elapsedRealtime() +
            startTime, 60*1000, pi);

}
}

Do not forget to register receiver to your manifest file--

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.shajib.customadapter">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <receiver
            android:name=".AlarmReceiver">
        </receiver>

    </application>

</manifest>