SignUpActivity.java

package com.example.taskboxx;

import android.app.ProgressDialog;
import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

public class SignUpActivity extends AppCompatActivity {

    public String userId;
    public Button signup_button;
    public EditText name;
    public EditText username;
    public EditText email;
    public EditText pwd;
    public EditText age;
    public EditText confirm_pwd;
    public ProgressDialog pd;
    private FirebaseAuth mAuth;
    private DatabaseReference mDatabase;

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

        mDatabase = FirebaseDatabase.getInstance().getReference();
        mAuth = FirebaseAuth.getInstance();
        signup_button = (Button) findViewById(R.id.SignUp);
        name = (EditText) findViewById(R.id.input_Name_SignUp);
        username = (EditText) findViewById(R.id.input_Username_SignUp);
        age = (EditText) findViewById(R.id.input_Age_SignUp);
        email = (EditText) findViewById(R.id.input_email_SignUp);
        pwd = (EditText) findViewById(R.id.input_NewPass_SignUp);
        confirm_pwd = (EditText) findViewById(R.id.input_RePass_SignUp);
        pd = new ProgressDialog(this);

    }


    public void SignUp(View view) {


        final String u_name = name.getText().toString();
        final String u_username = username.getText().toString();
        final String u_email = email.getText().toString();
        final String u_pwd = pwd.getText().toString();
        final String u_age = age.getText().toString();
        final String u_c_pwd = confirm_pwd.getText().toString();

        if (TextUtils.isEmpty(u_name) || TextUtils.isEmpty(u_username) || TextUtils.isEmpty(u_email) || TextUtils.isEmpty(u_pwd) || TextUtils.isEmpty(u_c_pwd)) {
            Toast.makeText(this, "Please Enter All the fields to proceed!", Toast.LENGTH_SHORT).show();
            return;
        } else {

            if (u_pwd.equals(u_c_pwd)) {