i develop app with java and firestore. i want to show user on my app randomly so i need to userId i wrote this code but not working randomly. how can i do randomly ?
public class MainMenu extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main_menu); FirebaseUser user= FirebaseAuth.getInstance().getCurrentUser(); String currentid=user.getUid(); DocumentReference reference; FirebaseFirestore firestore=FirebaseFirestore.getInstance(); reference=firestore.collection("Users").document(currentid); reference.get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() { @Override public void onComplete(@NonNull Task<DocumentSnapshot> task) { if(task.getResult().exists()){ DocumentSnapshot document= task.getResult(); String nameResult=task.getResult().getString("name"); String ageResult=task.getResult().getString("age"); String url=task.getResult().getString("profile_photo"); String eMail=task.getResult().getString("email"); List<String> hobbiesResult=(List<String>) document.get("Hobbies"); Map<String, Object> map = document.getData(); for (Map.Entry<String, Object> entry : map.entrySet()) { if (entry.getKey().equals("Hobbies")) { Log.d("TAG", entry.getValue().toString()); hobbies.setText(entry.getValue().toString()); } } Picasso.get().load(url).into(imageView); name.setText(nameResult); mail.setText(eMail); age.setText(ageResult); } } }); 
