threeDigitFormatter

public class ThreeDigitDecimalFormatWatcher implements TextWatcher {

    private DecimalFormat df;
    private DecimalFormat dfnd;
    private boolean hasFractionalPart;

    private EditText et;

    public ThreeDigitDecimalFormatWatcher(EditText et) {
        DecimalFormatSymbols decimalFormatSymbols = DecimalFormatSymbols.getInstance(Locale.US);
        df = new DecimalFormat("#,###.##", decimalFormatSymbols);
        df.setDecimalSeparatorAlwaysShown(true);
        dfnd = new DecimalFormat("#,###", decimalFormatSymbols);
        this.et = et;
        hasFractionalPart = false;
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        hasFractionalPart = s.toString().contains(String.valueOf(df.getDecimalFormatSymbols().getDecimalSeparator()));
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
    }

    @Override
    public void afterTextChanged(Editable s) {
        et.removeTextChangedListener(this);

        try {
            int inilen, endlen;
            inilen = et.getText().length();

            String v = s.toString().replace(String.valueOf(df.getDecimalFormatSymbols().getGroupingSeparator()), "");
//            Number n = df.parse(v);
            BigDecimal n = new BigDecimal(v);
            int cp = et.getSelectionStart();
            if (hasFractionalPart) {
                et.setText(df.format(n));
            } else {
                et.setText(dfnd.format(n));
            }
            endlen = et.getText().length();
            int sel = (cp + (endlen - inilen));
            if (sel > 0 && sel <= et.getText().length()) {
                et.setSelection(sel);
            } else {
                // place cursor at the end?
                et.setSelection(et.getText().length() - 1);
            }
        } catch (NumberFormatException nfe) {
            // do nothing?
        }

        et.addTextChangedListener(this);
    }
}