Validate an email inside an EditText [duplicate]

Question

I want to validate an email introduced inside an EditText and this the code that I already have:

final EditText textMessage = (EditText)findViewById(R.id.textMessage);

final TextView text = (TextView)findViewById(R.id.text);

    textMessage.addTextChangedListener(new TextWatcher() { 
        public void afterTextChanged(Editable s) { 
            if (textMessage.getText().toString().matches("[a-zA-Z0-9._-]+@[a-z]+.[a-z]+") && s.length() > 0)
            {
                text.setText("valid email");
            }
            else
            {
                text.setText("invalid email");
            }
        } 
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {} 
        public void onTextChanged(CharSequence s, int start, int before, int count) {} 
    }); 

The problem is that when I introduce 3 characters after the "@", it appears the message "valid email", when it must appear when I introduce the complete email.

Any suggerence?

Thank you all!

Answer 1

Just change your regular expression as follows:

"[a-zA-Z0-9._-]+@[a-z]+\\.+[a-z]+"

Because . (dot) means match any single-char.ADD a double backslash before your dot to stand for a real dot.

Answer 2

I wrote a library that extends EditText which supports natively some validation methods and is actually very flexible.

Current, as I write, natively supported (through xml attributes) validation methods are:

1. regexp: for custom regexp
2. numeric: for an only numeric field
3. alpha: for an alpha only field
4. alphaNumeric: guess what?
5. email: checks that the field is a valid email
6. creditCard: checks that the field contains a valid credit card using Luhn Algorithm
7. phone: checks that the field contains a valid phone number
8. domainName: checks that field contains a valid domain name ( always passes the test in API Level < 8 )
9. ipAddress: checks that the field contains a valid ip address webUrl: checks that the field contains a valid url ( always passes the test in API Level < 8 )
10. nocheck: It does not check anything. (Default)

You can check it out here: https://github.com/vekexasia/android-form-edittext

Hope you enjoy it :)

In the page I linked you'll be able to find also an example for email validation. I'll copy the relative snippet here:

<com.andreabaccega.widget.FormEditText
       style="@android:style/Widget.EditText"
       whatever:test="email"
       android:id="@+id/et_email"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:hint="@string/hint_email"
       android:inputType="textEmailAddress"
       />  

There is also a test app showcasing the library possibilities.

This is a screenshot of the app validating the email field.