Format credit card in edit text in android

Question

How to make EditText accept input in format:

4digit 4digit 4digit 4digit 

I tried Custom format edit text input android to acc

Answer 1

Not sure the TextWatcher is the right thing to use - we should use InputFilter

According to Android documentation, TextWatcher should be used for an external usage example : one [EditView] for password input + one [TextView] view which displays "weak", "strong", etc...

For Credit Card Format I am using InputFilter:

public class CreditCardInputFilter implements InputFilter {
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
        if (dest != null & dest.toString().trim().length() > 24) return null;
        if (source.length() == 1 && (dstart == 4 || dstart == 9 || dstart == 14))
            return " " + new String(source.toString());
        return null; // keep original
    }
}

And combine with a length filter (Android SDK) :

mEditCardNumber.setFilters(new InputFilter[]{
     new InputFilter.LengthFilter(24),
     new CreditCardInputFilter(),
});

This handle the case when typing and removing a digit.

(!) But this does not handle the case for a copy/paste of an entire string, this one should be done in a different InputFilter class

Hope it helps !