RegisterUserActivity

package com.projects.mikes.temperaturelogger;

import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.support.design.widget.TextInputEditText;
import android.support.v4.text.TextUtilsCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;

import com.eyro.mesosfer.Mesosfer;
import com.eyro.mesosfer.MesosferException;
import com.eyro.mesosfer.MesosferUser;
import com.eyro.mesosfer.RegisterCallback;

import java.util.Locale;

public class RegisterUser extends AppCompatActivity {
    private TextInputEditText txtEmail,txtPassword,txtFirstName,txtLastName;
    private String email,password,firstName,lastName;
    private ProgressDialog pdLoading;
    private AlertDialog adDialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_register_user);
        email = "";
        password = "";
        firstName = "";
        lastName = "";
        if(getSupportActionBar() != null){
            getSupportActionBar().setTitle("Register User");
        }

        txtEmail = (TextInputEditText)findViewById(R.id.txtEmail);
        txtPassword = (TextInputEditText)findViewById(R.id.txtPwd);
        txtFirstName = (TextInputEditText)findViewById(R.id.txtFirstName);
        txtLastName = (TextInputEditText)findViewById(R.id.txtLastName);

        pdLoading = new ProgressDialog(this);
        pdLoading.setIndeterminate(true);
        pdLoading.setCancelable(false);
        pdLoading.setCanceledOnTouchOutside(false);
    }

    public void handleRegister(View view){
        email = txtEmail.getText().toString();
        password = txtPassword.getText().toString();
        firstName = txtFirstName.getText().toString();
        lastName = txtLastName.getText().toString();

        if(!isInputValid()){
            return;
        }

        registerNewUser();

    }

    private boolean isInputValid(){
        if(TextUtils.isEmpty(email)){
            txtEmail.setError("Email must be filled");
            return false;
        }
        if(TextUtils.isEmpty(password)){
            txtPassword.setError("Password must be filled");
            return false;
        }
        if(TextUtils.isEmpty(firstName)){
            txtFirstName.setError("First Name must be filled");
            return false;
        }
        if(TextUtils.isEmpty(lastName)){
            txtLastName.setError("Last Name must be filled");
            return false;
        }
        return true;
    }
    private void registerNewUser(){
        pdLoading.setMessage("Registering new user, please wait...");
        pdLoading.show();

        MesosferUser newUser = MesosferUser.createUser();

        newUser.setEmail(email);
        newUser.setPassword(password);
        newUser.setFirstName(firstName);
        newUser.setLastName(lastName);

        newUser.registerAsync(new RegisterCallback() {
            @Override
            public void done(MesosferException e) {
                // hide progress dialog loading
                pdLoading.dismiss();

                // setup alert dialog builder
                AlertDialog.Builder builder = new AlertDialog.Builder(RegisterUser.this);
                builder.setNegativeButton(android.R.string.ok, null);

                // check if there is an exception happen
                if (e != null) {
                    builder.setTitle("Error Occured");
                    builder.setMessage(
                            String.format(Locale.getDefault(), "Error code: %d\nDescription: %s",
                                    e.getCode(), e.getMessage())
                    );
                    adDialog = builder.show();
                    return;
                }

                builder.setTitle("Register Success!");
                builder.setMessage("Thank you for registering!");
                adDialog = builder.show();
            }
        });
    }
}