java - Limit Decimal Places in Android EditText

Question

I'm trying to write an app that helps you manage your finances. I'm using an EditText Field where the user can specify an amount of money.

I set the inputType to numberDecimal which works fine, except that this allows people to enter numbers such as 123.122 which is not perfect for money.

Is there a way to limit the number of characters after the decimal point to two?

Answer 1

More elegant way would be using a regular expression ( regex ) as follows:

public class DecimalDigitsInputFilter implements InputFilter {

Pattern mPattern;

public DecimalDigitsInputFilter(int digitsBeforeZero,int digitsAfterZero) {
    mPattern=Pattern.compile("[0-9]{0," + (digitsBeforeZero-1) + "}+((\.[0-9]{0," + (digitsAfterZero-1) + "})?)||(\.)?");
}

@Override
public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {

        Matcher matcher=mPattern.matcher(dest);       
        if(!matcher.matches())
            return "";
        return null;
    }

}

To use it do:

editText.setFilters(new InputFilter[] {new DecimalDigitsInputFilter(5,2)});