My hashmap is not getting implemented in firebase database

I'm using this hashmap to transfer the username from one child(Users) to another(Notes) in database.

In my app you can create as well as update notes.

I want that every time a note is created or updated in the database a username is added along with the note. the username is saved in the users child.

But when the note is created the username doesn't show up. But when the note is updated, it is added in the child.

here is the code:

fAuth = FirebaseAuth.getInstance();
fNotesDatabase = FirebaseDatabase.getInstance().getReference()
.child("Notes").child(fAuth.getCurrentUser().getUid());
UsersRef = FirebaseDatabase.getInstance().getReference().child("Users");
current_user_id = fAuth.getCurrentUser().getUid();
btnCreate.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String title = etTitle.getText().toString().trim();
String content = etContent.getText().toString().trim();
if (!TextUtils.isEmpty(title) && !TextUtils.isEmpty(content)) {
createNote(title, content);
putUsername();
} else {
Snackbar.make(view, "Fill empty fields", Snackbar.LENGTH_SHORT).show();
}
}
});
private void putUsername() {
UsersRef.child(current_user_id).addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
String username = snapshot.child("username").getValue().toString();
HashMap usernameMap = new HashMap();
usernameMap.put("username", username);
fNotesDatabase.child(noteID).updateChildren(usernameMap);
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
}

I'm not able to understand as how come the username is added when the note is updated but not when the note us created.

I have updated the second note thats why there is a username but when is simply created the upper one there username is not showing.

EDIT

putData method :

     private void putData() {
if (isExist) {
fNotesDatabase.child(noteID).addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (dataSnapshot.hasChild("title") && dataSnapshot.hasChild("content")) {
String title = dataSnapshot.child("title").getValue().toString();
String content = dataSnapshot.child("content").getValue().toString();
etTitle.setText(title);
etContent.setText(content);
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
}

createNote method:

     private void createNote(String title, String content) {
if (fAuth.getCurrentUser() != null) {
Calendar calFordDate = Calendar.getInstance();
SimpleDateFormat currentDate = new SimpleDateFormat("dd-MMMM-yyyy");
saveCurrentDate = currentDate.format(calFordDate.getTime());
if (isExist) {
Map updateMap = new HashMap();
updateMap.put("title", etTitle.getText().toString().trim());
updateMap.put("content", etContent.getText().toString().trim());
updateMap.put("timestamp", ServerValue.TIMESTAMP);
updateMap.put("date",saveCurrentDate);
fNotesDatabase.child(noteID).updateChildren(updateMap);
SendUsersToPostActivity();
Toast.makeText(this, "Article updated", Toast.LENGTH_SHORT).show();
} else {
final DatabaseReference newNoteRef = fNotesDatabase.push();
final Map noteMap = new HashMap();
noteMap.put("title", title);
noteMap.put("content", content);
noteMap.put("timestamp", ServerValue.TIMESTAMP);
noteMap.put("date",saveCurrentDate);
Thread mainThread = new Thread(new Runnable() {
@Override
public void run() {
newNoteRef.setValue(noteMap).addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
Toast.makeText(NewNoteActivity.this, "Article Created", Toast.LENGTH_SHORT).show();
SendUsersToPostActivity();
} else {
Toast.makeText(NewNoteActivity.this, "ERROR: " + task.getException().getMessage(), Toast.LENGTH_SHORT).show();
}
}
});
}
});
mainThread.start();
}
}
}

It's hard to be certain, but I don't see where you set the noteID value that putUsername depends on.

In general though, I'd recommend changing createNote to take all the data that it needs for the new note, including the user name:

btnCreate.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String title = etTitle.getText().toString().trim();
String content = etContent.getText().toString().trim();
if (!TextUtils.isEmpty(title) && !TextUtils.isEmpty(content) && fAuth.getCurrentUser() != null) {
UsersRef.child(current_user_id).child("username").addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
String username = snapshot.getValue(String.class);
createNote(title, content, current_user_id, username);
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
throw error.toException()
}
});
} else {
Snackbar.make(view, "Fill empty fields", Snackbar.LENGTH_SHORT).show();
}
}
});
private void createNote(String title, String content, String uid, String username) {
Calendar calFordDate = Calendar.getInstance();
SimpleDateFormat currentDate = new SimpleDateFormat("dd-MMMM-yyyy");
saveCurrentDate = currentDate.format(calFordDate.getTime());
Map updateMap = new HashMap();
updateMap.put("title", title);
updateMap.put("content", content);
updateMap.put("timestamp", ServerValue.TIMESTAMP);
updateMap.put("date",saveCurrentDate);
updateMap.put("uid",uid);
updateMap.put("username",username);
final DatabaseReference noteRef = isExist ? fNotesDatabase.push() : fNotesDatabase.child(noteID);
noteRef.updateChildren(noteMap).addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
Toast.makeText(NewNoteActivity.this, "Article "+(isExists ? "updated" : "created"), Toast.LENGTH_SHORT).show();
SendUsersToPostActivity();
} else {
Toast.makeText(NewNoteActivity.this, "ERROR: " + task.getException().getMessage(), Toast.LENGTH_SHORT).show();
}
}
});
}

Some of the changes in this code versus yours:

• Looks up the user name before creating the new note. Uses a addListenerForSingleValueEvent for this, to ensure we only do this once for every button click.
• Only loads the username child of the user profile, since that's all you use.
• Use the values you pass into createNote instead of recalculating them from the UI views.
• Only has a single write to the database, as updateChildren works fine for creating the initial data too.
• There is no need to run the Firebase setValue call on a new thread, as Firebase runs it off the main thread already.
• Please don't leave onCancelled empty, as it may hide important error messages.