Develop Reference

Multiuser in Android Studio using Realtime Firebase

When I run the codes, it does not show any error. I have no problem to login as guardian but when I try to login as elderly it couldn't and I don't know what's the problem. What I want is when a user input the username and password, it will validate from database and direct the user according to different user type.
Segment codes of Login.java:
private Boolean validateUsername() {
String val = username.getEditText().getText().toString();
if (val.isEmpty()) {
username.setError("Field cannot be empty");
return false;
} else {
username.setError(null);
username.setErrorEnabled(false);
return true;
}
}
private Boolean validatePassword() {
String val = password.getEditText().getText().toString();
if (val.isEmpty()) {
password.setError("Field cannot be empty");
return false;
} else {
password.setError(null);
password.setErrorEnabled(false);
return true;
}
}
public void loginUser(View view) {
//validate login info
if (!validateUsername() || !validatePassword()) {
return;
} else {
isUser();
}
}
private void isUser() {
DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference();
databaseReference.child("user").addListenerForSingleValueEvent(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
String input1 = username.getEditText().getText().toString();
String input2 = password.getEditText().getText().toString();
if (dataSnapshot.child(input1).exists()) {
if (dataSnapshot.child(input1).child("password").getValue(String.class).equals(input2)) {
if (active.isChecked()) {
if (dataSnapshot.child(input1).child("radioGuardian").getValue(String.class).equals("Guardian")) {
preferences.setDataLogin(Login.this, true);
preferences.setDataAs(Login.this, "Guardian");
startActivity(new Intent(Login.this, dashboardGuardian.class));
} else if (dataSnapshot.child(input1).child("radioElderly").getValue(String.class).equals("Elderly")) {
preferences.setDataLogin(Login.this, true);
preferences.setDataAs(Login.this, "Elderly");
startActivity(new Intent(Login.this, dashboardUser.class));
}
} else {
if (dataSnapshot.child(input1).child("radioGuardian").getValue(String.class).equals("Guardian")) {
preferences.setDataLogin(Login.this, false);
startActivity(new Intent(Login.this, dashboardGuardian.class));
} else if (dataSnapshot.child(input1).child("radioElderly").getValue(String.class).equals("Elderly")) {
preferences.setDataLogin(Login.this, false);
startActivity(new Intent(Login.this, dashboardUser.class));
}
}
} else {
password.setError("Wrong Password");
password.requestFocus();
}
} else {
username.setError("No such User exist");
username.requestFocus();
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
}
});
}
protected void onStart() {
super.onStart();
if (preferences.getDataLogin(this)) {
if (preferences.getDataAs(this).equals("Guardian")) {
startActivity(new Intent(this, dashboardGuardian.class));
finish();
} else {
startActivity(new Intent(this, dashboardUser.class));
finish();
}
}
}
}
Codes of Register.java:
public class Register extends AppCompatActivity {
//Variables
TextInputLayout regUsername, regEmail, regPhoneNo, regPassword;
RadioGroup radioGroup;
RadioButton selectedElderly, selectedGuardian;
Button regBtn, regToLoginBtn;
UserHelperClass helperClass;
int i = 0;
FirebaseDatabase rootNode;
DatabaseReference reference;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
//Hooks to all xml elements in activity_register.xml
regUsername = findViewById(R.id.reg_username);
regEmail = findViewById(R.id.reg_email);
regPhoneNo = findViewById(R.id.reg_phoneNo);
regPassword = findViewById(R.id.reg_password);
regBtn = findViewById(R.id.reg_btn);
regToLoginBtn = findViewById(R.id.reg_login_btn);
radioGroup = findViewById(R.id.radio_type);
selectedGuardian = findViewById(R.id.radioGuardian);
selectedElderly = findViewById(R.id.radioElderly);
helperClass = new UserHelperClass();
regBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (validateUsername() && validateEmail() && validatePhoneNo() && validateUserType() && validatePassword() == true) {
Intent intent = new Intent(Register.this, Login.class);
startActivity(intent);
} else {
validateUsername();
validateEmail();
validatePhoneNo();
validateUserType();
validatePassword();
}
rootNode = FirebaseDatabase.getInstance();
reference = rootNode.getReference("user");
//Get all the values
String m1 = selectedElderly.getText().toString();
String m2 = selectedGuardian.getText().toString();
String username = regUsername.getEditText().getText().toString();
String password = regPassword.getEditText().getText().toString();
helperClass.setUsername(regUsername.getEditText().getText().toString());
helperClass.setEmail(regEmail.getEditText().getText().toString());
helperClass.setPhoneNo(regPhoneNo.getEditText().getText().toString());
helperClass.setPassword(regPassword.getEditText().getText().toString());
if (selectedElderly.isChecked()) {
helperClass.setRadioElderly(m1);
} else {
helperClass.setRadioGuardian(m2);
}
reference.child(username).setValue(helperClass);
}
});
regToLoginBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Register.this, Login.class);
startActivity(intent);
}
});
}
private Boolean validateUsername() {
String val = regUsername.getEditText().getText().toString();
String noWhiteSpace = "\\A\\w{4,20}\\z";
if (val.isEmpty()) {
regUsername.setError("Field cannot be empty");
return false;
} else if (val.length() >= 15) {
regUsername.setError("Username too long");
return false;
} else if (!val.matches(noWhiteSpace)) {
regUsername.setError("White space is not allowed");
return false;
} else {
regUsername.setError(null);
regUsername.setErrorEnabled(false);
return true;
}
}
private Boolean validateEmail() {
String val = regEmail.getEditText().getText().toString();
String emailPattern = "[a-zA-Z0-9._-]+#[a-z]+\\.+[a-z]+";
if (val.isEmpty()) {
regEmail.setError("Field cannot be empty");
return false;
} else if (!val.matches(emailPattern)) {
regEmail.setError("Invalid email address");
return false;
} else {
regEmail.setError(null);
return true;
}
}
private Boolean validatePhoneNo() {
String val = regPhoneNo.getEditText().getText().toString();
if (val.isEmpty()) {
regPhoneNo.setError("Field cannot be empty");
return false;
} else {
regPhoneNo.setError(null);
return true;
}
}
private Boolean validateUserType() {
if (radioGroup.getCheckedRadioButtonId() == -1) {
Toast.makeText(this, "Please select user type", Toast.LENGTH_SHORT).show();
return false;
} else {
return true;
}
}
private Boolean validatePassword() {
String val = regPassword.getEditText().getText().toString();
String passwordVal = "^" +
"(?=.*[0-9])" + //at least 1 digit
"(?=.*[a-z])" + //at least 1 lower case letter
"(?=.*[A-Z])" + //at least 1 upper case letter
"(?=.*[a-zA-Z])" + //any letter
"(?=.*[##$%^&+=])" + //at least 1 special character
"(?=\\S+$)" + //no white space
".{4,}" + //at least 4 characters
"$";
if (val.isEmpty()) {
regPassword.setError("Field cannot be empty");
return false;
} else if (!val.matches(passwordVal)) {
regPassword.setError("Password is too weak");
return false;
} else {
regPassword.setError(null);
regPassword.setErrorEnabled(false);
return true;
}
}
public void registerUser(View view) {
if (!validateUsername() | !validatePassword() | !validatePhoneNo() | !validateEmail() | validateUserType()) {
return;
}
//Get all the values
String m1 = selectedElderly.getText().toString();
String m2 = selectedGuardian.getText().toString();
helperClass.setUsername(regUsername.getEditText().getText().toString());
helperClass.setEmail(regEmail.getEditText().getText().toString());
helperClass.setPhoneNo(regPhoneNo.getEditText().getText().toString());
helperClass.setPassword(regPassword.getEditText().getText().toString());
if (selectedElderly.isChecked()) {
helperClass.setRadioElderly(m1);
} else {
helperClass.setRadioGuardian(m2);
}
reference.child(String.valueOf(i + 1)).setValue(helperClass);
}
}
Database structure

If you post your database structure that would be more helpful.
As per your code.
you have two children in input1
'radioGuardian' and 'radioElderly'
have you added both values on registration? Or it will be null. And it will produce nullPointEx.
Hence the issue is here!
if (selectedElderly.isChecked()) {
helperClass.setRadioElderly(m1);
} else {
helperClass.setRadioGuardian(m2);
}
Try to change it to:-
if (selectedElderly.isChecked()) {
helperClass.setRadioElderly(m1);
helperClass.setRadioGuardian("NA");
} else {
helperClass.setRadioGuardian(m2);
helperClass.setRadioElderly("NA");
}

Android If statement not breaking when condition is true

In this activity I am creating an account for users. I am using mobsandgeeks.saripaar API for validation features. To allow the activity to work I currently print the errors to an invisible text field, if this textfield has text, the activity does not go onto the next activity (i.e. there is an issue with user input).
I am having a problem with the if statement that checks if the username or email already exists in the database. When condition is true (checked in logs), the account is not created, but the 'Account created' message is still displayed and the application still goes to the next activity.
Any help on this would be much appreciated. Thanks
CreateAccount.java
DatabaseHelper myDb;
private static final String TAG = "CreateAccount";
//http://learningprogramming.net/mobile/android/form-validation-in-android/
#NotEmpty
#Length(min = 3, max = 10)
private EditText etUsername;
#NotEmpty
private EditText etUserAddress;
#NotEmpty
private EditText etFirstName;
#NotEmpty
private EditText etLastName;
#NotEmpty
#Email
private EditText etEmail;
#NotEmpty
#Pattern(regex = "(^\\(?([0-9]{3})\\)?[-.\\s]?([0-9]{3})[-.\\s]?([0-9]{4})$)")
private EditText etPhone;
#NotEmpty
private EditText etPaypal;
//Valid = abcABC123!
#NotEmpty
#Password(scheme = Password.Scheme.ALPHA_NUMERIC_SYMBOLS)
private EditText etPassword;
#ConfirmPassword
EditText etConfirmPassword;
Button btnCreateAccount;
TextView check;
//https://www.youtube.com/watch?v=rt-8PgncIio
ImageView profileImageView;
Button btnProfilePic;
private static final int SELECT_PHOTO = 1;
private static final int CAPTURE_PHOTO = 2;
ProgressDialog progressBar;
int progressBarStatus;
Handler progressBarHandler = new Handler();
Bitmap thumbnail;
private Validator validator;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create_account);
myDb = new DatabaseHelper(this);
validator = new Validator(this);
validator.setValidationListener(this);
etUsername = findViewById(R.id.etUsername);
etFirstName = findViewById(R.id.etFirstName);
etLastName = findViewById(R.id.etLastName);
etUserAddress = findViewById(R.id.etAddress);
etEmail = findViewById(R.id.etEmail);
etPassword = findViewById(R.id.etPasswordLogin);
etConfirmPassword = findViewById(R.id.etConfirmPasswordLogin);
etPhone = findViewById(R.id.etPhoneNo);
etPaypal = findViewById(R.id.etPaypalName);
btnCreateAccount = findViewById(R.id.btnCreateAccount);
check = findViewById(R.id.tvCheck);
btnProfilePic = findViewById(R.id.btnProfilePicture);
profileImageView = findViewById(R.id.imageProfile);
btnProfilePic.setOnClickListener(this);
//(https://www.youtube.com/watch?v=rt-8PgncIio) Image
//had to change permissions in the Android Manifest file to allow for camera to be used
if (ContextCompat.checkSelfPermission(CreateAccount.this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
profileImageView.setEnabled(false);
ActivityCompat.requestPermissions(CreateAccount.this, new String[]{Manifest.permission.CAMERA, Manifest.permission.WRITE_EXTERNAL_STORAGE}, 0);
} else {
profileImageView.setEnabled(true);
}
createAccount();
}
public void createAccount() {
btnCreateAccount.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
validator.validate();
//(https://www.youtube.com/watch?v=rt-8PgncIio) Image
profileImageView.setDrawingCacheEnabled(true);
profileImageView.buildDrawingCache();
Bitmap bitmap = profileImageView.getDrawingCache();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
byte[] data = baos.toByteArray();
String email1 = etEmail.getText().toString().trim();
Log.d(TAG, "onClick: email " + email1);
String username = etUsername.getText().toString().trim();
Log.d(TAG, "onClick: username " + username);
boolean emailExists = myDb.checkIfEmailAlreadyExists(email1);
Log.d(TAG, "onClick: emailExists " + emailExists);
boolean usernameExists = myDb.checkIfUsernameAlreadyExists(username);
Log.d(TAG, "onClick: usernameExists " + usernameExists);
//https://stackoverflow.com/questions/6290531/check-if-edittext-is-empty
if (etUsername.getText().toString().matches("") | etFirstName.getText().toString().matches("") | etLastName.getText().toString().matches("")
| etEmail.getText().toString().matches("") | etUserAddress.getText().toString().matches("") | etPassword.getText().toString().matches("")|
etConfirmPassword.getText().toString().matches("") | etPhone.getText().toString().matches("") | etPaypal.getText().toString().matches(""))
{
Toast.makeText(CreateAccount.this, "Please fill empty fields", Toast.LENGTH_LONG).show();
}
else if(check.getText().toString().matches("") == false) {
Toast.makeText(CreateAccount.this, "Please enter correct details", Toast.LENGTH_SHORT).show();
}
else {
if (usernameExists){
Log.d(TAG, "onClick: userExists " + usernameExists);
Toast.makeText(CreateAccount.this, "This username is already registered", Toast.LENGTH_LONG).show();
check.setText("TEXT");
}
else if (emailExists){
Log.d(TAG, "onClick: emailExists" + emailExists);
Toast.makeText(CreateAccount.this, "This email is already registered", Toast.LENGTH_LONG).show();
check.setText("TEXT");
}
else if (usernameExists == false | emailExists == false) {
boolean checktext = check.getText().equals("");
// original CRUD video - https://www.youtube.com/watch?v=kDZES1wtKUY&list=PLS1QulWo1RIaRdy16cOzBO5Jr6kEagA07&index=8
boolean isInserted = myDb.insertUserData(etUsername.getText().toString(), etUserAddress.getText().toString(), etFirstName.getText().toString(), etLastName.getText().toString(),
etEmail.getText().toString(), etPassword.getText().toString(), etPhone.getText().toString(),
etPaypal.getText().toString(), data);
if (isInserted == true) {
if (checktext == true) {
onValidationSucceeded();
}
else if (checktext == false){
Toast.makeText(CreateAccount.this, "Account not Created", Toast.LENGTH_LONG).show();
}
}
} else {
Toast.makeText(CreateAccount.this, "Account not Created", Toast.LENGTH_LONG).show();
}
}
}
});
}
//http://learningprogramming.net/mobile/android/form-validation-in-android/
#Override
public void onValidationFailed(List<ValidationError> errors) {
for (ValidationError error : errors) {
View view = error.getView();
//TextView check = findViewById(R.id.tvCheck);
String message = error.getCollatedErrorMessage(this);
// Display error messages
if (view instanceof EditText) {
((EditText) view).setError(message);
} else {
Toast.makeText(this, message, Toast.LENGTH_LONG).show();
}
check.setText(errors.toString());
}
}
//http://learningprogramming.net/mobile/android/form-validation-in-android/
#Override
public void onValidationSucceeded() {
Toast.makeText(CreateAccount.this, "Account Created, Please sign in", Toast.LENGTH_LONG).show();
Intent intent = new Intent(CreateAccount.this, Login.class);
startActivity(intent);
}

You have a problem in your condition:
Instead of:
else if (usernameExists == false | emailExists == false)
It should be:
else if (usernameExists == false && emailExists == false)
which means user/email not exist, insert them in DB and navigate to next activity.

Validation Of SignUp Fails

I have made a fragment in which I am validating a Register form, it works fine sometime but after few seconds the app stops without showing any message nor I have any error log...I don't know what happens.
Here is my code:
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_register, container, false);
RegUsername = (EditText) view.findViewById(R.id.RegUsername);
RegEmailId = (EditText) view.findViewById(R.id.RegEmailId);
RegPhoneNo = (EditText) view.findViewById(R.id.RegPhoneNo);
RegPassword = (EditText) view.findViewById(R.id.RegPassword);
RegisterButton = (Button) view.findViewById(R.id.Register);
RegisterButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Register(); }})};
return view; }
private void Register() {
initialize();
if (!registerfail()) {
Toast.makeText(getActivity(), "Registration failed! || Try Again", Toast.LENGTH_SHORT).show();
} else {
registerok();
}
}
private void registerok() {
Toast.makeText(getActivity(), "Welcome " + Username, Toast.LENGTH_SHORT);
}
private boolean registerfail() {
boolean validation = true;
if (Username.isEmpty() || Username.length() > 25) {
RegUsername.setError("Invalid username");
validation = false;
}
if (EmailId.isEmpty() || !Patterns.EMAIL_ADDRESS.matcher(EmailId).matches()) {
RegEmailId.setError("Invalid EmailId");
validation = false; }
}
if (PhoneNo.isEmpty()) {
RegPhoneNo.setError("Invalid PhoneNo.");
validation = false; }
}
if (Password.isEmpty()) {
RegPassword.setError("Invalid Password");
validation = false;}
}
return validation; }
private void initialize() {
Username = RegUsername.getText().toString().trim();
EmailId = RegEmailId.getText().toString().trim();
PhoneNo = RegPhoneNo.getText().toString().trim();
Password = RegPassword.getText().toString().trim(); }}

//set validation = false if any if condition is failed
private boolean registerfail() {
boolean validation = true;
if (Username.isEmpty() || Username.length() > 25) {
RegUsername.setError("Invalid username");
validation = false;
}
if (EmailId.isEmpty() || !Patterns.EMAIL_ADDRESS.matcher(EmailId).matches()) {
RegEmailId.setError("Invalid EmailId");
validation = false;
}
if (PhoneNo.isEmpty()) {
RegPhoneNo.setError("Invalid PhoneNo.");
validation = false;
}
if (Password.isEmpty()) {
RegPassword.setError("Invalid Password");
validation = false;
}
return validation;
}

try this way my friend
String emailAddress = RegEmailId.getText().toString().trim();
if (RegPassword.getText().toString().length() < 6) {
RegPassword.setError(getString("password minimum contain 6 character"));
RegPassword.requestFocus();
}
if (RegPassword.getText().toString().equals("")) {
RegPassword.setError(getString("please enter password"));
RegPassword.requestFocus();
}
if (RegPhoneNo.getText().toString().equals("")) {
RegPhoneNo.setError(getString("please enter password"));
RegPhoneNo.requestFocus();
}
if (!android.util.Patterns.EMAIL_ADDRESS.matcher(emailAddress).matches()) {
RegEmailId.setError(getString("please enter valid email address"));
RegEmailId.requestFocus();
}
if (RegEmailId.getText().toString().equals("")) {
RegEmailId.setError(getString("please enter email address"));
RegEmailId.requestFocus();
}
if (!emailAddress.equals("") &&
RegPassword.getText().toString().length() >= 6 &&
!RegPassword.getText().toString().trim().equals("")
&& android.util.Patterns.EMAIL_ADDRESS.matcher(emailAddress).matches() &&
!RegPhoneNo.getText().toString().equals("")&&
RegPhoneNo.getText().toString().length()>=10) {
// do your action
}

Android Email Validation on EditText

I have one edittext and I would to to write email validation in my Editttext
this is a xml code
<EditText
android:id="#+id/mail"
android:layout_width="match_parent"
android:layout_height="48dp"
android:layout_alignLeft="#+id/phone"
android:layout_below="#+id/phone"
android:layout_marginRight="33dp"
android:layout_marginTop="10dp"
android:background="#drawable/edit_background"
android:ems="10"
android:hint="E-Mail"
android:inputType="textEmailAddress"
android:paddingLeft="20dp"
android:textColor="#7e7e7e"
android:textColorHint="#7e7e7e" >
</EditText>
and this is a java code
emailInput = mail.getText().toString().trim();
emailPattern = "^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*#[A-Za-z0-9]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
if (emailInput.matches(emailPattern)) {
Toast.makeText(getActivity(), "valid email address", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getActivity(), "Invalid email address", Toast.LENGTH_SHORT).show();
mail.setBackgroundResource(R.drawable.edit_red_line);
}
I can't validation. The toast message is always "Invalid email address".
What am I doing wrong?

Why not use:
public final static boolean isValidEmail(CharSequence target) {
return !TextUtils.isEmpty(target) && android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
As suggested here.

I am posting very simple and easy answer of email validation without using any string pattern.
1.Set on click listener on button....
button_resetPassword.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
CharSequence temp_emilID=username.getText().toString();//here username is the your edittext object...
if(!isValidEmail(temp_emilID))
{
username.requestFocus();
username.setError("Enter Correct Mail_ID ..!!");
or
Toast.makeText(getApplicationContext(), "Enter Correct Mail_ID", Toast.LENGTH_SHORT).show();
}
else
{
correctMail..
//Your action...
}
});
2.call the isValidEmail() i.e..
public final static boolean isValidEmail(CharSequence target)
{
if (TextUtils.isEmpty(target))
{
return false;
} else {
return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
}
I hope it will helpful for you...

Android Email Validation Simplest way
String validemail= "[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
"\\#" +
"[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
"(" +
"\\." +
"[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
")+";
String emal=email.getText().toString();
Matcher matcherObj = Pattern.compile(validemail).matcher(emal);
if (matcherObj.matches()) {
Toast.makeText(getApplicationContext(), "enter
all details", Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(),"please enter
valid email",Toast.LENGTH_SHORT).show();
}

Try following code:
public final static boolean isValidEmail(CharSequence target) {
return !TextUtils.isEmpty(target) && android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
This works fine.

String emailPattern = "[a-zA-Z0-9._-]+#[a-z]+\\.+[a-z]+";
if(emailId.getText().toString().isEmpty()) {
Toast.makeText(getApplicationContext(),"enter email address",Toast.LENGTH_SHORT).show();
else {
if (emailId.getText().toString().trim().matches(emailPattern)) {
Toast.makeText(getApplicationContext(),"valid email address",Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getApplicationContext(),"Invalid email address", Toast.LENGTH_SHORT).show();
}
}

here is a whole code for login validations......
public class LoginActivity extends AppCompatActivity {
private static final String TAG = "LoginActivity";
private static final int REQUEST_SIGNUP = 0;
#Bind(R.id.input_email) EditText _emailText;
#Bind(R.id.input_password) EditText _passwordText;
#Bind(R.id.btn_login) Button _loginButton;
#Bind(R.id.link_signup) TextView _signupLink;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
ButterKnife.bind(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);
finish();
overridePendingTransition(R.anim.push_left_in, R.anim.push_left_out);
}
});
}
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;
}
}

Use this function for validating email id:
private boolean validateEmaillId(String emailId){
return Pattern.compile("^(([\\w-]+\\.)+[\\w-]+|([a-zA-Z]{1}|[\\w-]{2,}))#"
+ "((([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\.([0-1]?"
+ "[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\."
+ "([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\.([0-1]?"
+ "[0-9]{1,2}|25[0-5]|2[0-4][0-9])){1}|"
+ "([a-zA-Z]+[\\w-]+\\.)+[a-zA-Z]{2,4})$").matcher(emailId).matches();
}

I had a query in email pattern for more than one Email ID validation and for only one Email ID.I solved it by using :
public static final String patter_emails="^(\\s*,?\\s*[0-9a-za-z]([-.\\w]*[0-9a-za-z])*#([0-9a-za-z][-\\w]*[0-9a-za-z]\\.)+[a-za-z]{2,9})+\\s*$";
public static final String patter_email="^(\\s*[0-9a-za-z]([-.\\w]*[0-9a-za-z])*#([0-9a-za-z][-\\w]*[0-9a-za-z]\\.)+[a-za-z]{2,9})+\\s*$";
These above is used for pattern in Java and Android both.
check this by using:
pattern test: rubular.com

android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches()

private void isValidEmail(String email_id) {
if (email_id == null){
checkTextView.setVisibility(View.VISIBLE);
checkTextView.setText(LocaleController.getString("EnterValidEmail", R.string.EnterValidEmail));
return;
}
if (android.util.Patterns.EMAIL_ADDRESS.matcher(email_id).matches()) {
checkTextView.setVisibility(View.GONE);
} else {
checkTextView.setVisibility(View.VISIBLE);
checkTextView.setText(LocaleController.getString("EnterValidEmail", R.string.EnterValidEmail));
}
Take a textView ex.checkTextView and validate when the email is valid then the textview is gone otherwise it show the message

Try this code
String emailPattern = "(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])";
if (!tvEmail.matches(Constants.emailPattern)){
tvEmail.setError("Invalid Email ");
}
else{
//your code
}

String emailPattern = "(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")#(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])";
if (!"anan.pp#gmail.co".matches(Constants.emailPattern)){
//tvEmail.setError("Invalid Email ");
} else {
// your code
}

Try below code:
Just call below method like,
if(emailValidator(mail.getText().toString())){
Toast.makeText(getActivity(), "valid email address",
Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(getActivity(), "invalid email address",
Toast.LENGTH_SHORT).show();
}
public static boolean emailValidator(final String mailAddress) {
Pattern pattern;
Matcher matcher;
final String EMAIL_PATTERN = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*#" + "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
pattern = Pattern.compile(EMAIL_PATTERN);
matcher = pattern.matcher(mailAddress);
return matcher.matches();
}

Assign a String variable to store the value of this EditText:
emailInput = mail.getText().toString().trim();
Use setError in your EditText:
if(!isValidEmail(emailInput)){
mail.setError("Invalid"); /*"Invalid Text" or something like getString(R.string.Invalid)*/
mail.requestFocus();
}
Create a method to check the email:
private boolean isValidEmail(String emailInput) {
String EMAIL_PATTERN = "^[_A-Za-z0-9-\\+]+(\\.[_A-Za-z0-9-]+)*#"
+ "[A-Za-z0-9-]+(\\.[A-Za-z0-9]+)*(\\.[A-Za-z]{2,})$";
Pattern pattern = Pattern.compile(EMAIL_PATTERN);
Matcher matcher = pattern.matcher(emailInput);
return matcher.matches();
}

Email Validation on EditText in android

I wrote following code for login but when I type "\" after email-id, it accepts and log in successfully (it doesn't accepts any other symbols or characters only accepts "\").
I don't want that it login with "\".`
#Override
public void onCreate(Bundle savedInstanceState) {
try {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setSoftInputMode(
WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
setContentView(R.layout.main);
WiztangoBaseApplication.InitDialogBox(WiztangoActivity.this);
this.pref = PreferenceManager.getDefaultSharedPreferences(this);
loginStatus = (TextView)findViewById(R.id.login_status);
register = (Button) findViewById(R.id.btnregister);
register.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
RegisterIntent();
}
});
login = (Button) findViewById(R.id.btlogin);
password = (EditText) findViewById(R.id.txtPwd);
username = (EditText) findViewById(R.id.txtemail);
saveLoginCheckBox = (CheckBox)findViewById(R.id.saveLoginCheckBox);
pref = getSharedPreferences(Constants.PREFS_NAME,
MODE_PRIVATE);
String usernamestr = pref.getString(Constants.PREF_USERNAME, "");
String passwordsharestr = pref.getString(Constants.PREF_PASSWORD,
"");
username.setText(usernamestr);
password.setText(passwordsharestr);
saveLogin = pref.getBoolean("saveLogin", false);
if (saveLogin == true) {
username.setText(usernamestr);
password.setText(passwordsharestr);
saveLoginCheckBox.setChecked(true);
}
login.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
try {
//Constants.clearInfo();
getSharedPreferences(Constants.PREFS_NAME, MODE_PRIVATE)
.edit()
.putString(Constants.PREF_USERNAME,
username.getText().toString())
.putString(Constants.PREF_PASSWORD,
password.getText().toString())
.putString(Constants.PREF_CHECKED, "TRUE")
.commit();
if (username.getText().toString().trim().equals("")) {
username.setError(Html
.fromHtml("Please Enter Username"));
username.requestFocus();
} else if (password.getText().toString().trim()
.equals("")) {
password.setError(Html
.fromHtml("Please Enter Password"));
password.requestFocus();
} else {
if (Constants
.checkInternetConnection(WiztangoActivity.this)) {
Constants.userpass = password.getText()
.toString();
new AuthenticData().execute();
} else {
WiztangoBaseApplication.ShowThisDialog("Error",
"Please check internet connection.");
}
if (saveLoginCheckBox.isChecked()) {
prefEditor.putBoolean("saveLogin", true);
prefEditor.putString(Constants.PREF_USERNAME,
username.getText().toString());
prefEditor.putString(Constants.PREF_PASSWORD,
password.getText().toString());
saveLoginCheckBox.setChecked(true);
prefEditor.commit();
} else {
SharedPreferences mPreferences = getSharedPreferences(Constants.PREFS_NAME, MODE_PRIVATE);
SharedPreferences.Editor editor=mPreferences.edit();
editor.remove(Constants.PREF_USERNAME);
editor.remove(Constants.PREF_PASSWORD);
editor.commit();
}
}
} catch (Exception e) {
Log.e("Exception In Wiztango/", e.toString());
e.printStackTrace();
}
}
});
} catch (Exception e) {
Log.e("Exception In Wiztango/", e.toString());
e.printStackTrace();
}
}

Inbuilt Patterns Provides Email Validation like:
if (!android.util.Patterns.EMAIL_ADDRESS.matcher(emailStr).matches() && !TextUtils.isEmpty(emailStr)) {
emailEditText.setError("Invalid Email");
emailEditText.requestFocus();
}

Heyy, check this answer here: https://stackoverflow.com/a/7882950/1739882
It says:
public final static boolean isValidEmail(CharSequence target) {
if (target == null) {
return false;
} else {
return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
}

You can use this code for check is Valid Email or not:
public final static boolean isValidEmail(CharSequence target) {
if (target == null) {
return false;
} else {
return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
}

Best Approach
Validate email and isEmpty in one method.
public final static boolean isValidEmail(CharSequence target)
{
return !TextUtils.isEmpty(target) && android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}

public static boolean isEmailValid(String email) {
boolean isValid = false;
String expression = "^[\\w\\.-]+#([\\w\\-]+\\.)+[A-Z]{2,4}$";
CharSequence inputStr = email;
Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(inputStr);
if (matcher.matches()) {
isValid = true;
}
return isValid;
}

Try out the below method to validate the Email address.
private boolean validateEmail(EditText editText, String p_nullMsg, String p_invalidMsg)
{
boolean m_isValid = false;
try
{
if (p_editText != null)
{
if(validateForNull(editText,p_nullMsg))
{
Pattern m_pattern = Pattern.compile("([\\w\\-]([\\.\\w])+[\\w]+#([\\w\\-]+\\.)+[A-Za-z]{2,4})");
Matcher m_matcher = m_pattern.matcher(editText.getText().toString().trim());
if (!m_matcher.matches() && editText.getText().toString().trim().length() > 0)
{
m_isValid = false;
editText.setError(p_invalidMsg);
}
else
{
m_isValid = true;
}
}
else
{
m_isValid = false;
}
}
else
{
m_isValid = false;
}
}
catch(Throwable p_e)
{
p_e.printStackTrace(); // Error handling if application crashes
}
return m_isValid;
}

Try this code:--
public final static boolean isValidEmail(CharSequence target) {
if (target == null) {
return false;
} else {
return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
}
}