Set notification for specific date and time

Question

how to create a notification for specific date and time in android studio without using service?

Answer 1

use the class AlarmManager that runs a code at the background. put this code in the main Activity:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.your layout);
    boolean alarm = (PendingIntent.getBroadcast(this, 0, new Intent("ALARM"), PendingIntent.FLAG_NO_CREATE) == null);

    if(alarm){
        Intent itAlarm = new Intent("ALARM");
        PendingIntent pendingIntent = PendingIntent.getBroadcast(this,0,itAlarm,0);
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeInMillis(System.currentTimeMillis());
        calendar.add(Calendar.SECOND, 3);
        AlarmManager alarme = (AlarmManager) getSystemService(ALARM_SERVICE);
        alarme.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(),60000, pendingIntent);
    }
}

create a new class that will control if it is at the hour to notify.

public class BroadcastManager extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
    try {
        String yourDate = "04/01/2016";
        String yourHour = "16:45:23";
        Date d = new Date();
        DateFormat date = new SimpleDateFormat("dd/MM/yyyy");
        DateFormat hour = new SimpleDateFormat("HH:mm:ss");
        if (date.equals(yourDate) && hour.equals(yourHour)){
            Intent it =  new Intent(context, MainActivity.class);
            createNotification(context, it, "new mensage", "body!", "this is a mensage");
        }
    }catch (Exception e){
        Log.i("date","error == "+e.getMessage());
    }
}


public void createNotification(Context context, Intent intent, CharSequence ticker, CharSequence title, CharSequence descricao){
    NotificationManager nm = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
    PendingIntent p = PendingIntent.getActivity(context, 0, intent, 0);

    NotificationCompat.Builder builder = new NotificationCompat.Builder(context);
    builder.setTicker(ticker);
    builder.setContentTitle(title);
    builder.setContentText(descricao);
    builder.setSmallIcon(R.drawable.yourIcon);
    builder.setContentIntent(p);
    Notification n = builder.build();
    //create the notification
    n.vibrate = new long[]{150, 300, 150, 400};
    n.flags = Notification.FLAG_AUTO_CANCEL;
    nm.notify(R.drawable.yourIcon, n);
    //create a vibration
    try{

        Uri som = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        Ringtone toque = RingtoneManager.getRingtone(context, som);
        toque.play();
    }
    catch(Exception e){}
}

in the manifest put this:

  <receiver
        android:name="BroadcastManager"
        android:label="BroadcastReceiverAux">
        <intent-filter>
            <action android:name="ALARM" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </receiver>

give this permission:

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"