LoginPresenter.java

package com.sample.medicalconferenceapp.login;

import android.text.TextUtils;

import com.sample.medicalconferenceapp.R;
import com.sample.medicalconferenceapp.login.LoginContract.Presenter;
import com.sample.medicalconferenceapp.model.UserRepo;
import com.sample.medicalconferenceapp.model.pojo.UserPojo;

/**
 * Created by kshitij on 14/8/16.
 */
public class LoginPresenter implements Presenter {

    private final LoginContract.View view;

    public LoginPresenter(LoginContract.View view) {
        this.view = view;
        setupDummyUsers();
    }

    void setupDummyUsers() {
        UserPojo admin = new UserPojo();
        admin.setEmail("admin@admin.com");
        admin.setPassword("admin");
        admin.setType(UserPojo.ADMIN);

        UserPojo doc1 = new UserPojo();
        doc1.setEmail("doc1@doc.com");
        doc1.setPassword("doc1");
        doc1.setType(UserPojo.DOCTOR);

        UserPojo doc2 = new UserPojo();
        doc2.setEmail("doc2@doc.com");
        doc2.setPassword("doc2");
        doc2.setType(UserPojo.DOCTOR);

        UserRepo userRepo = new UserRepo();
        userRepo.createOrUpdateTopics(admin);
        userRepo.createOrUpdateTopics(doc1);
        userRepo.createOrUpdateTopics(doc2);

    }

    @Override
    public void onClickLogin(String email, String password) {
        boolean cancelLogin = false;

        // Check for a valid email address.
        cancelLogin = !isEmailValid(email);
        cancelLogin = !isPasswordValid(password);

        if (!cancelLogin) {
            UserRepo userRepo = new UserRepo();
            if (userRepo.isUserValid(email, password)) {
                view.goToMainScreen();
            } else {
                view.showEmailError(R.string.error_invalid_email);
                view.showPasswordError(R.string.error_invalid_password);
            }

        }
    }

    private boolean isEmailValid(String email) {
        if (TextUtils.isEmpty(email)) {
            view.showEmailError(R.string.error_field_required);
            return false;
        } else if (!email.contains("@")) {
            view.showEmailError(R.string.error_invalid_email);
            return false;
        }
        return true;
    }

    private boolean isPasswordValid(String password) {
        if (!TextUtils.isEmpty(password) && password.length() > 1) {
            return true;
        } else {
            view.showPasswordError(R.string.error_invalid_password);
        }
        return false;
    }
}