Registration Activity Demo for Reactive Programming in Android tutorial ()

RegistrationDemoActivity.java

package com.rohmanhakim.androidreactivedemo;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class RegistrationDemoActivity extends AppCompatActivity {

    EditText etEmail;
    TextView textEmailAlert;
    EditText etPassword;
    TextView textPasswordAlert;
    EditText etPasswordConfirmation;
    TextView textPasswordConfirmationAlert;
    Button btnSubmit;

    Retrofit retrofit;

    SampleService service;

    Call<List<String>> emailCalls;

    TextWatcher emailChangedListener;
    TextWatcher passwordChangedListener;
    TextWatcher passwordConfirmationChangedListener;

    boolean emailValid;
    boolean passwordValid;
    boolean passwordConfirmationValid;

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

        // Inisialisasi form
        etEmail = (EditText) findViewById(R.id.et_email);
        textEmailAlert = (TextView) findViewById(R.id.text_email_alert);
        etPassword = (EditText) findViewById(R.id.et_password);
        textPasswordAlert = (TextView) findViewById(R.id.text_password_alert);
        etPasswordConfirmation = (EditText) findViewById(R.id.et_password_confirmation);
        textPasswordConfirmationAlert = (TextView) findViewById(R.id.text_password_confirmation_alert);
        btnSubmit = (Button) findViewById(R.id.btn_submit);

        // Inisialisasi state (keadaan) default form
        textEmailAlert.setVisibility(View.GONE);
        textPasswordAlert.setVisibility(View.GONE);
        textPasswordConfirmationAlert.setVisibility(View.GONE);
        btnSubmit.setEnabled(false);
        emailValid = false;
        passwordValid = false;
        passwordConfirmationValid = false;

        // Inisialisasi edittext TextChanged() listener, untuk:
        // field email,
        emailChangedListener = new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                validateEmail();
            }
        };

        // field password
        passwordChangedListener = new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                validatePassword();
                validatePasswordConfirmation();
            }
        };

        // dan field password confirmation
        passwordConfirmationChangedListener = new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                validatePasswordConfirmation();
            }
        };

        // Tambahkan text changed listener untuk semua field
        etEmail.addTextChangedListener(emailChangedListener);
        etPassword.addTextChangedListener(passwordChangedListener);
        etPasswordConfirmation.addTextChangedListener(passwordConfirmationChangedListener);

        // Inisialisasi retrofit
        retrofit = new Retrofit.Builder()
                .baseUrl(getString(R.string.base_url))
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        // Inisialisasi service sample
        service = retrofit.create(SampleService.class);



    }

    public void validateEmail(){
        // jika user mengetik 3 karakter atau lebih di field email, trigger API call untuk mendapatkan daftar email
        final String input = etEmail.getText().toString();
        emailCalls = service.getEmails();
        if(input.length() >= 3){
            emailCalls.enqueue(new Callback<List<String>>() {
                @Override
                public void onResponse(Call<List<String>> call, Response<List<String>> response) {
                    // jika email sudah tersedia, tampilkan peringatan
                    if(response.body().contains(input.trim())){
                        showEmailExistAlert(true);
                        emailValid = false;
                    } else {
                        showEmailExistAlert(false);
                        emailValid = true;
                    }
                    validateButton();
                }

                @Override
                public void onFailure(Call<List<String>> call, Throwable t) {
                    // cukup tampilkan toast jika ada error
                    Toast.makeText(RegistrationDemoActivity.this,t.getMessage(),Toast.LENGTH_SHORT).show();
                }
            });
        }
    }

    public void validatePassword(){
        // jika password < 6 karakter, tampilkan peringatan
        String input = etPassword.getText().toString();
        if(!input.equals("") && input.length() < 6){
            showPasswordMinimalAlert(true);
            passwordValid = false;
        } else {
            showPasswordMinimalAlert(false);
            passwordValid = true;
        }
        validateButton();
    }

    public void validatePasswordConfirmation(){
        // jika konfirmasi password tidak sesuai tampilkan peringatan
        String input = etPasswordConfirmation.getText().toString();
        if(!input.equals(etPassword.getText().toString())){
            showPasswordConfirmationAlert(true);
            passwordConfirmationValid = false;
        } else {
            passwordConfirmationValid = true;
            showPasswordConfirmationAlert(false);
        }
        validateButton();
    }

    public void validateButton(){
        // jika semua field sudah terisi, enable button submit
        if(!etEmail.getText().toString().equals("")
                && !etPassword.getText().toString().equals("")
                && !etPasswordConfirmation.getText().toString().equals("")
                && emailValid
                && passwordValid
                && passwordConfirmationValid){
           btnSubmit.setEnabled(true);
        } else {
            btnSubmit.setEnabled(false);
        }
    }

    public void showEmailExistAlert(boolean value){
        if(value == true) {
            textEmailAlert.setText(getString(R.string.email_exist_alert));
            textEmailAlert.setVisibility(View.VISIBLE);
        } else {
            textEmailAlert.setVisibility(View.GONE);
        }
    }

    public void showPasswordMinimalAlert(boolean value){
        if(value == true) {
            textPasswordAlert.setText(getString(R.string.password_minimal_alert));
            textPasswordAlert.setVisibility(View.VISIBLE);
        } else {
            textPasswordAlert.setVisibility(View.GONE);
        }
    }

    public void showPasswordConfirmationAlert(boolean value){
        if(value == true){
            textPasswordConfirmationAlert.setText(getString(R.string.password_confirmation_does_not_match_alert));
            textPasswordConfirmationAlert.setVisibility(View.VISIBLE);
        } else {
            textPasswordConfirmationAlert.setVisibility(View.GONE);
        }
    }
}