Notifications in a given time and on mobile phone

Question

Hello. I’m making an android app that notifies me when I have to deliver a school assignment and, if it’s the day of the task or the day before, I want to be notified at certain times.

The home screen is where the service is started, where I click on "Tasks" to go to Task Activity.

public class DashboardActivity extends Activity {

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

    startService(new Intent(this, ShowNotificationService.class));
}
}

But I would like the service to start when the phone was turned on (as Whatsapp shows messages notifications when we turn on the mobile).

Code of showNotificationService.class

public class ShowNotificationService extends Service {

private EducInDAO dao;
private DatabaseHelper helper;
private Context context;

@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate() {
    super.onCreate();
    helper = new DatabaseHelper(this);
    try {
        tarefas();
    } catch (ParseException e) {
        e.printStackTrace();
    }
}

public void tarefas() throws ParseException {
    SQLiteDatabase db = helper.getReadableDatabase();

    Cursor cursor = db.rawQuery("SELECT * FROM tarefas", null);

    if (cursor == null) {

    } else {
        while(cursor.moveToNext()) {

            SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
            Date dataEntrega = new Date(cursor.getLong(2));
            Date dateNow = new Date();

            String dataEntregaFormatada = sdf.format(dataEntrega);
            String dateNowFormatada = sdf.format(dataEntrega);

            GregorianCalendar calendar = new GregorianCalendar();
            int hora = calendar.get(Calendar.HOUR_OF_DAY);


            if ((dateNowFormatada.compareTo(dataEntregaFormatada) == 0) || (dateNowFormatada.compareTo(dataEntregaFormatada) == 1)) {
                int id = cursor.getInt(0);
                String nomeMateria = cursor.getString(1);

                String title = "Eae, já fez?";

                if ((dateNowFormatada.compareTo(dataEntregaFormatada) == 0)) {
                    if ((hora == 0 || hora == 7 || hora == 12 || hora == 23)) {
                        if ((hora == 0 || hora == 7 || hora == 12)) {
                            String contentText = "Você tem tarefa de " + nomeMateria + " para hoje!";
                            Vibrator v = (Vibrator) this.getSystemService(Context.VIBRATOR_SERVICE);
                            v.vibrate(1000);
                            showNotification(title, contentText, id, 1);
                        }
                    }
                } else if ((dateNowFormatada.compareTo(dataEntregaFormatada) == 1)) {
                    if ((hora == 15 || hora == 18 || hora == 22)) {
                        String contentText = "Você tem tarefa de " + nomeMateria + " para amanhã!";
                        Vibrator v = (Vibrator) this.getSystemService(Context.VIBRATOR_SERVICE);
                        v.vibrate(1000);
                        showNotification(title, contentText, id, 1);
                    }
                }
            }
        }
    }

    cursor.close();
}


public void showNotification(String title, String content, int id, int tipoNotificacao) {

    NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
            .setContentTitle(title)
            .setContentText(content)
            .setAutoCancel(true);;

    TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);

    if (tipoNotificacao == 1) {
        mBuilder.setSmallIcon(R.drawable.homework);

        Intent resultIntent = new Intent(this, TarefasActivity.class);
        resultIntent.putExtra(Constantes.TAREFA_ID, String.valueOf(id));

        stackBuilder.addParentStack(TarefasActivity.class);
        stackBuilder.addNextIntent(resultIntent);
    }

    PendingIntent resultPendingIntent =
            stackBuilder.getPendingIntent(
                    0,
                    PendingIntent.FLAG_CANCEL_CURRENT
            );

    mBuilder.setContentIntent(resultPendingIntent);

    NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    mNotificationManager.notify(id, mBuilder.build());
}

}

But what happens is that it shows the notifications, for example, at 10 pm but if I take the notification, it appears again! So it’s take that shows again :/

How to solve?

Answer 1

To run a service when the mobile phone is turned on you have to register a Broadcastreceiver to respond to action android.intent.action.BOOT_COMPLETED.

In the Androidmanifest.xml register your Broadcastreceiver:

<receiver android:name="aSuaPackage.StartUpBootReceiver">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED" />
    </intent-filter>
</receiver>  

Add this permission:

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

Define the Broadcastreceiver that will launch your service:

public class StartUpBootReceiver extends BroadcastReceiver {

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

        if (Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())) {

            // Chame aqui o seu serviço
        }
    }
}  

In the service set a method to record notifications.
This method uses the Alarmmanager to launch a Broadcastreceiver which will create the notifications at the date/time specified in the parameter date.
Call this method for each notification you want to create.

private void AgendarNotificacao(Date data) {

 // Obtém um novo calendário e define a data para a data da notificação
    Calendar calendar = Calendar.getInstance();
    calendar.setTime(data);

 // Obtém um alarm manager
    AlarmManager alarmManager = (AlarmManager) getApplicationContext().getSystemService(getBaseContext().ALARM_SERVICE);

 // O id a ser usado no pending intent
    int id = (int) System.currentTimeMillis();

 // Prepara o intent que deverá ser lançado na data definida
    Intent intent = new Intent(this, CriarNotificacao.class);

 // Obtém o pending intent
    PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(), id, intent, PendingIntent.FLAG_UPDATE_CURRENT);

 // Regista o alerta no sistema.
    alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent);
}  

As you have more than one type of notification enter the parameters you need to build the notification. Pass this information to Intent through Intent.putExtra();

Define the Broadcastreceiver which will be launched by the Alarmmanager registered by the previous method. This Broadcastreceiver is responsible for creating the notification.

public class CriarNotificacao extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent paramIntent) {

    // Obtenha os 'Extra' que passou e crie aqui a notificação

}

Register it on Androidmanifest.xml.

<receiver android:name="aSuaPackage.CriarNotificação"/>  

Notes:

• It is necessary to execute the application once before it can respond to android.intent.action.BOOT_COMPLETED action. The same applies if your execution has been stopped using Force Close.
• The application needs to be installed in the cellular memory.