android - Android Notification Builder声音不起作用

我尝试了这里提出的许多建议，但对我没有任何帮助。
这是我的源代码:

Intent resultIntent = new Intent(this, MainActivity.class);
PendingIntent contentIntent = PendingIntent.getActivity(this, 0, resultIntent,PendingIntent.FLAG_UPDATE_CURRENT);
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
.setSmallIcon(R.drawable.ic_launcher)
.setContentTitle("title")
.setContentText("Hello World!");
mBuilder.setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION));
mBuilder.setContentIntent(contentIntent);
NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
mNotificationManager.notify(0, mBuilder.build());

通知出现，但没有声音，有帮助吗？

最佳答案

设置默认标志:

mBuilder.setDefaults(Notification.DEFAULT_SOUND|Notification.DEFAULT_LIGHTS|Notification.DEFAULT_VIBRATE);