How to get user uid from firebase on android?
<p>I want to save data to firebase. This is my Activity Code :</p>

<pre><code>private Firebase firebaseRef;
Firebase.setAndroidContext(this);

try {
    mUserId = firebaseRef.getAuth().getUid();
} catch (Exception e) {
    //  loginWithMailView();
}
itemsUrl = Constants.FIREBASE_URL + "/Person/" + mUserId +"/Information/";

//Person + null (?) + the other information
</code></pre>

<p>and this is for my button code :</p>

<pre><code>buttonSave = (Button) findViewById(R.id.btnKaydolKayit);
buttonSave.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        firebaseRef = new Firebase(Constants.FIREBASE_URL);
        String name = editTextName.getText().toString().trim();
        String surname = editTextSurname.getText().toString().trim();
        String gender = final_result.getText().toString();
        String mail = editTextMail.getText().toString();
        String pass = editTextPass.getText().toString().trim();
        String phone = editTextPhone.getText().toString().trim();
        String trom = final_resultT.getText().toString();
        String bloodGroup = spinnerBlood.getSelectedItem().toString();
        String dateBlood = dateTextViewBlood.getText().toString();
        String dateTrombo = dateTextViewTrom.getText().toString();

        if (pass.isEmpty() || mail.isEmpty()) {
            AlertDialog.Builder builder = new AlertDialog.Builder(KaydolActivity.this);
            builder.setMessage(R.string.signup_error_message)
                    .setTitle(R.string.signup_error_title)
                    .setPositiveButton(android.R.string.ok, null);
            AlertDialog dialog = builder.create();
            dialog.show();
        } else {
            firebaseRef.createUser(mail, pass, new Firebase.ResultHandler(){

                @Override
                public void onSuccess() {
                    firebaseRef = new Firebase(Constants.FIREBASE_URL);
                    //  firebaseRef.setValue();
                    AlertDialog.Builder builder = new AlertDialog.Builder(KaydolActivity.this);
                    builder.setMessage("Hesap başarılı bir şekilde oluşturuldu!").setPositiveButton(R.string.login_button_label, new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            Intent intent = new Intent(KaydolActivity.this, loginWithMail.class);
                            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
                            startActivity(intent);
                        }
                    });
                    AlertDialog dialog = builder.create();
                    dialog.show();
                }

                @Override
                public void onError(FirebaseError firebaseError) {
                    AlertDialog.Builder builder = new AlertDialog.Builder(KaydolActivity.this);
                    builder.setMessage(firebaseError.getMessage())
                            .setTitle(R.string.signup_error_title)
                            .setPositiveButton(android.R.string.ok, null);
                    AlertDialog dialog = builder.create();
                    dialog.show();
                }
            });
        }

        new Firebase(itemsUrl).push().child("name").setValue(name);
        new Firebase(itemsUrl).push().child("surname").setValue(surname);
        new Firebase(itemsUrl).push().child("gender").setValue(gender);
        new Firebase(itemsUrl).push().child("mail").setValue(mail);
        new Firebase(itemsUrl).push().child("pass").setValue(pass);
        new Firebase(itemsUrl).push().child("phone").setValue(phone);
        new Firebase(itemsUrl).push().child("trom").setValue(trom);
        new Firebase(itemsUrl).push().child("bloodGroup").setValue(bloodGroup);
        new Firebase(itemsUrl).push().child("trom").setValue(trom);
        new Firebase(itemsUrl).push().child("dateBlood").setValue(dateBlood);
        new Firebase(itemsUrl).push().child("dateTrombo").setValue(dateTrombo);
    }
});
</code></pre>

<p>my source code (for help / for example ) :  <a href="https://www.sitepoint.com/creating-a-cloud-backend-for-your-android-app-using-firebase/" rel="noreferrer">https://www.sitepoint.com/creating-a-cloud-backend-for-your-android-app-using-firebase/</a></p>

<p>When I save a data to firebase as the following photo ( Login&amp;Auth ) 
<a href="https://i.stack.imgur.com/ZVlve.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ZVlve.png" alt="enter image description here"></a></p>

<p>but mUserId is null. so when I look database mUserid is null ( like a photo )
<a href="https://i.stack.imgur.com/IfZaL.png" rel="noreferrer"><img src="https://i.stack.imgur.com/IfZaL.png" alt="enter image description here"></a></p>