我在那里使用firebase我可以看到添加新的“Child”时，我需要在添加新子时显示通知 我正在使用此代码，但它不起作用
（通知工作但只是在活动中显示，我需要在用户离开应用时显示通知，例如facebook或whatsapp
方法：
public Notification createNotification(boolean makeHeadsUpNotification) {
Notification.Builder notificationBuilder = new Notification.Builder(this)
.setSmallIcon(R.drawable.ic_settings_real_black_24dp)
.setPriority(Notification.PRIORITY_DEFAULT)
.setContentTitle("Sample Notification")
.setContentText("This is a normal notification.");
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
notificationBuilder.setCategory(Notification.CATEGORY_MESSAGE);
}
if (makeHeadsUpNotification) {
Intent push = new Intent();
push.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
push.setClass(this, UserActivity.class);
PendingIntent fullScreenPendingIntent = PendingIntent.getActivity(this, 0,
push, PendingIntent.FLAG_CANCEL_CURRENT);
notificationBuilder
.setContentText("Heads-Up Notification on Android L or above.")
.setFullScreenIntent(fullScreenPendingIntent, true);
}
return notificationBuilder.build();
}
//添加子项时的通知方法
mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// THIS METHODS ARE IN THE ONCREATE
mListener = FirebaseUtils.getCHATSOLICITUDRef("8HaKY67AjaOD2a6QKrABhR2rcaJ3").addChildEventListener(new ChildEventListener() {
@Override
public void onChildAdded(DataSnapshot dataSnapshot, String s) {
/// THE METHOD IS IN THIS
mNotificationManager.notify(1, createNotification(
true));
}
@Override
public void onChildChanged(DataSnapshot dataSnapshot, String s) {
}
@Override
public void onChildRemoved(DataSnapshot dataSnapshot) {
}
@Override
public void onChildMoved(DataSnapshot dataSnapshot, String s) {
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}