如何在.whereEqualTo中获取EditText用户名。FireStore？

EditText editText = findViewById(R.id.editText);
String username = editText.getText().toString();

CollectionReference usersRef = FirebaseFirestore.getInstance().collection("users");

Query query = usersRef.whereEqualTo("username", username);

query.get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
    @Override
    public void onComplete(@NonNull Task<QuerySnapshot> task) {
        if (task.isSuccessful()) {
            for (QueryDocumentSnapshot document : task.getResult()) {
                // 处理查询结果
            }
        } else {
            // 处理查询失败
        }
    }
});