AliAsadi

new Notification.Builder(context)
        .setContentTitle(title)
        .setContentText(contentText)
        .setSmallIcon(R.drawable.icon)
        .setContentIntent(intent);

AliAsadi

private static String longArrayToString(long[] values) {
    StringBuffer sb = new StringBuffer();
    if (values != null) {
        for (int i = 0; i < values.length - 1; i++) {
            sb.append(values[i]).append(DELIMITER);
        }
        sb.append(values[values.length - 1]);
    }
    return sb.toString();
}

AliAsadi

if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
   NotificationChannel channel = new NotificationChannel(CHANNEL_ID, "Default", NotificationManager.IMPORTANCE_DEFAULT);
        channel.setVibrationPattern(new long[0]);
        channel.enableVibration(false);
        channel.setSound(null,null);
        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        if (notificationManager != null) {
            notificationManager.createNotificationChannel(channel);
        }
}

AliAsadi

if (vibrationPattern !=null && vibrationPattern.lenght > 0){
            this.mVibrationEnabled = true;
            this.mVibration = vibrationPattern
        }else{
            this.mVibrationEnabled = false;
            this.mVibration = null;
        }

AliAsadi

public class SingletonManager {

    private static SingletonManager singleton;
    private Context context;

    private SingletonManager(Context context) {
        this.context = context;
    }

    public synchronized static SingletonManager getInstance(Context context) {

AliAsadi

SingletonManager.getInstance(getApplicationContext());

AliAsadi

public class SingletonManager {
   // ....
    public synchronized static SingletonManager getInstance(Context context) {
        if (singleton == null) {
            singleton = new SingletonManager(context.getApplicationContext());
        }
        return singleton;
    }
}

AliAsadi

public class LoginActivity extends Activity {
      @Override
    protected void onCreate(Bundle savedInstanceState) {
        //...
        SingletonManager.getInstance(this);
    }
}

AliAsadi

public class LoginActivity extends Activity implements LocationListener {

  @Override
  public void onLocationUpdated(Location location){
  // do something
  }
  
  @Override
  protected void onStart(){
    LocationManager.getInstance().register(this);

AliAsadi

protected void onDestroy() {
    unregisterReceivers();
    LocationManager.getInstance().unregister(this);  
    AppState.getInstance().setStateChangeListener(null);
    LocalBroadcastManager.getInstance(getApplicationContext())
        .unregisterReceiver(messageReciver);
    super.onDestroy();
}