Notes

package com.sourcey.materiallogindemo;

import android.app.ProgressDialog;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

import android.content.Intent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import butterknife.ButterKnife;
import butterknife.InjectView;

public class LoginActivity extends AppCompatActivity {
private static final String TAG = "LoginActivity";
private static final int REQUEST_SIGNUP = 0;

@InjectView(R.id.input_email) EditText _emailText;
@InjectView(R.id.input_password) EditText _passwordText;
@InjectView(R.id.btn_login) Button _loginButton;
@InjectView(R.id.link_signup) TextView _signupLink;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
ButterKnife.inject(this);

_loginButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
login();
}
});

_signupLink.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
// Start the Signup activity
Intent intent = new Intent(getApplicationContext(), SignupActivity.class);
startActivityForResult(intent, REQUEST_SIGNUP);
}
});
}

public void login() {
Log.d(TAG, "Login");

if (!validate()) {
onLoginFailed();
return;
}

_loginButton.setEnabled(false);

final ProgressDialog progressDialog = new ProgressDialog(LoginActivity.this,
R.style.AppTheme_Dark_Dialog);
progressDialog.setIndeterminate(true);
progressDialog.setMessage("Authenticating...");
progressDialog.show();

String email = _emailText.getText().toString();
String password = _passwordText.getText().toString();

// TODO: Implement your own authentication logic here.

new android.os.Handler().postDelayed(
new Runnable() {
public void run() {
// On complete call either onLoginSuccess or onLoginFailed
onLoginSuccess();
// onLoginFailed();
progressDialog.dismiss();
}
}, 3000);
}


@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_SIGNUP) {
if (resultCode == RESULT_OK) {

// TODO: Implement successful signup logic here
// By default we just finish the Activity and log them in automatically
this.finish();
}
}
}

@Override
public void onBackPressed() {
// disable going back to the MainActivity
moveTaskToBack(true);
}

public void onLoginSuccess() {
_loginButton.setEnabled(true);
finish();
}

public void onLoginFailed() {
Toast.makeText(getBaseContext(), "Login failed", Toast.LENGTH_LONG).show();

_loginButton.setEnabled(true);
}

public boolean validate() {
boolean valid = true;

String email = _emailText.getText().toString();
String password = _passwordText.getText().toString();

if (email.isEmpty() || !android.util.Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
_emailText.setError("enter a valid email address");
valid = false;
} else {
_emailText.setError(null);
}

if (password.isEmpty() || password.length() < 4 || password.length() > 10) {
_passwordText.setError("between 4 and 10 alphanumeric characters");
valid = false;
} else {
_passwordText.setError(null);
}

return valid;
}
}