phone verification


package net.simplifiedcoding.firebasephoneauth;

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.android.gms.tasks.TaskExecutors;
import com.google.firebase.FirebaseException;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.PhoneAuthCredential;
import com.google.firebase.auth.PhoneAuthProvider;

import java.util.concurrent.TimeUnit;

public class VerifyPhoneActivity extends AppCompatActivity {


    private String verificationId;
    private FirebaseAuth mAuth;
    private ProgressBar progressBar;
    private EditText editText;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_verify_phone);

        mAuth = FirebaseAuth.getInstance();

        progressBar = findViewById(R.id.progressbar);
        editText = findViewById(R.id.editTextCode);

        String phonenumber = getIntent().getStringExtra("phonenumber");
        sendVerificationCode(phonenumber);

        findViewById(R.id.buttonSignIn).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                String code = editText.getText().toString().trim();

                if (code.isEmpty() || code.length() < 6) {

                    editText.setError("Enter code...");
                    editText.requestFocus();
                    return;
                }
                verifyCode(code);
            }
        });

    }

    private void verifyCode(String code) {
        PhoneAuthCredential credential = PhoneAuthProvider.getCredential(verificationId, code);
        signInWithCredential(credential);
    }

    private void signInWithCredential(PhoneAuthCredential credential) {
        mAuth.signInWithCredential(credential)
                .addOnCompleteListener(new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {

                            Intent intent = new Intent(VerifyPhoneActivity.this, ProfileActivity.class);
                            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);

                            startActivity(intent);

                        } else {
                            Toast.makeText(VerifyPhoneActivity.this, task.getException().getMessage(), Toast.LENGTH_LONG).show();
                        }
                    }
                });
    }

    private void sendVerificationCode(String number) {
        progressBar.setVisibility(View.VISIBLE);
        PhoneAuthProvider.getInstance().verifyPhoneNumber(
                number,
                60,
                TimeUnit.SECONDS,
                TaskExecutors.MAIN_THREAD,
                mCallBack
        );

    }