Real time database firebase - firebase-realtime-database

Question

I have some problems with Real time Database of Firebase for my Android App, because I can’t see any data. I don’t know why, I have also changed the rules yet.
I have three classes in my Android project: LogIn, SignUp (for registration) and Profile. When I write "name", "username","lastname", "email" and "password" in the SignUp class, then I can see the "name" "lastname" and "username" in the Profile, but not in the Real time DataBase.
Here there is part of the code:
SignUp:
declaration of variables:
private lateinit var dbReference: DatabaseReference
private lateinit var firebaseDatabase: FirebaseDatabase
and then.....
rebaseDatabase = FirebaseDatabase.getInstance()
dbReference = firebaseDatabase.getReference("users")
dbReference.setValue("First users")
val currentDb = dbReference.child((currentUser?.uid!!))
currentDb.child("name").setValue(name)
currentDb.child("lastname").setValue(lastName)
currentDb.child("user").setValue(user)
currentDb.child("email").setValue(email)
currentDb.child("pass").setValue(pass)
Profile class:
database = FirebaseDatabase.getInstance()
databaseReference = database?.reference!!.child("users")
override fun onDataChange(snapshot: DataSnapshot) {
val usernameText = findViewById<TextView>(R.id.usernameText)
val nameText = findViewById<TextView>(R.id.nameText)
val lastnameText = findViewById<TextView>(R.id.lastnameText)
usernameText.text = snapshot.child("user").value?.toString()
nameText.text= snapshot.child("name").value?.toString()
lastnameText.text= snapshot.child("lastname").value?.toString()
}
[enter image description here][1]
[1]: https://i.stack.imgur.com/liW2z.jpg

Answer 1

Can you try this in ur Signup:
private lateinit var dbReference: DatabaseReference
dbReference = Firebase.database.reference;
dbReference.child("users").setValue("First users")
instead of
private lateinit var dbReference: DatabaseReference
private lateinit var firebaseDatabase: FirebaseDatabase.getInstance()
dbReference = firebaseDatabase.getReference("users")
dbReference.setValue("First users")
you may have jumbled up java and kotlin code. As shown in the page https://firebase.google.com/docs/database/android/read-and-write
UPDATE :
I would like to add something. I didnt see this at first but it seems important and is mentioned in page https://firebase.google.com/docs/database/android/read-and-write
Can you try this
dbReference = Firebase.database("https://soundbliss-8ba73-default-rtdb.europe-west1.firebasedatabase.app").reference;
instead of
dbReference = Firebase.database.reference;
If this doesn't work, find out the database url of your firebase project and then pass it as an argument to the database function like this
dbReference = Firebase.database("database url of ur app").reference;