Change DecimalFormat locale

I have custom DecimalFormat in Edittext's addTextChangedListener method, everything is working perfectly but when I change language (locale) my addTextChangedListener is not working.

double answer = inputDouble * counterToDouble;
DecimalFormat df = new DecimalFormat("##.########");
// df=(DecimalFormat)numberFormat;

df.setRoundingMode(RoundingMode.DOWN);
answer = Double.parseDouble(df.format(answer));

unicoinsAmmount.setText(String.valueOf(df.format(answer)));

I searched about my problem and found a NumberFormat solution:

NumberFormat numberFormat = NumberFormat.getNumberInstance(Locale.US);

but I don't know how I can use this code.

You can specify locale for DecimalFormat this way:

DecimalFormatSymbols symbols = new DecimalFormatSymbols(Locale.US);
DecimalFormat format = new DecimalFormat("##.########", symbols);

You may try by first converting to NumberFormat and then Cast it to DecimalFormat

Integer vc = 3210000;
NumberFormat nf = NumberFormat.getNumberInstance(Locale.US);
DecimalFormat formatter = (DecimalFormat) nf;
formatter.applyPattern("#,###,###");
String fString = formatter.format(vc);
return convertNumbersToEnglish(fString);

You can use basic constructor for setting Locale while creating DecimalFormat object:

DecimalFormat dFormat = new DecimalFormat("#.#", new DecimalFormatSymbols(Locale.US));

Use simply this method to convert current localization wise number,

public static String currencyFormatter(String balance) {
    try {
        double amount = Double.parseDouble(balance);
        DecimalFormat decimalFormat = new DecimalFormat("##,##,##,###.##");
        DecimalFormat locationSpecificDF = null;
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
            locationSpecificDF = (DecimalFormat) DecimalFormat.getNumberInstance(Locale.forLanguageTag("bn")); // Ex. en, bn etc.
        } else {
            return decimalFormat.format(amount);
        }
        return locationSpecificDF.format(amount);
    } catch (Exception e) {
        return balance;
    }
}

or follow this link.

if you want to use only NumberFormat, you can do this way:

unicoinsAmmount.setText(NumberFormat.getNumberInstance(Locale.US).format(vc));

You can specify the number of fraction digit after the decimal point, and/or the numbers before the decimal point. Of-course, setting the current locale is also important.

   private String formatNumber(double number) {

    NumberFormat nf = NumberFormat.getNumberInstance(Locale.getDefault());
    if (nf instanceof DecimalFormat) {
        try {
            DecimalFormat formatter = (DecimalFormat) nf;
            formatter.setDecimalSeparatorAlwaysShown(true);
            formatter.setMinimumFractionDigits(2);
            formatter.setMaximumFractionDigits(2);
            return formatter.format(new BigDecimal(number);
        } catch (NumberFormatException nfe) {
            nfe.printStackTrace();
        }
    }
    return null;
}

you can create an extension function like below

 fun Double.toRate(): String? {
        val symbols = DecimalFormatSymbols(Locale.US)
        val decimalFormat = DecimalFormat("##.######", symbols)
        decimalFormat .minimumFractionDigits = 2
        return decimalFormat .format(this)
    }

Thanks