What's wrong with my email validation??
TextInputLayout useremail_layout = (TextInputLayout) findViewById(R.id.email_layout);
String email = "";
String emailPattern = "[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+";
if (email.matches(emailPattern)&& email.length()>0) {
    useremail_layout.setError("valid address");
} else  {
     useremail_layout.setError("invalid email");
     Email.setError(null);  
}
 
     
    