what's the best way to apply a mask to an EditText on Android?

Question

what's the best way to mask a EditText on Android?
I Would like my EditText to behave like this decimal number input here. Is there a easy way to do this?

Answer 1

I built a decimal mask for an edit text that will auto change the edit text to the number of decimal places you want. Bascially, you listen for text changes and loss of focus.

    private void formatNumber() {
    sNumberToFormat = etNumberToFormat.getText().toString();
    sDecimalMask = etDecimalMask.getText().toString();
    boolean periodMask = false;
    String delimiter = getDelimiter();
    String[] decimalMask = getsDecimalMask();


    if (decimalMask.length == 1) {
        return;
    } else {

        if (delimiter.equalsIgnoreCase(",")) {
            //decimal format only currently works with dot delimiters.
            sDecimalMask = sDecimalMask.replace(",", ".");
        }

        DecimalFormat df = new DecimalFormat(sDecimalMask);
        df.setRoundingMode(RoundingMode.UP);

        sNumberToFormat = df.format(Float.valueOf(sNumberToFormat.replace(",", ".")));
        //if (maxNumber > Float.valueOf(sNumberToFormat)) {
        if (delimiter.equalsIgnoreCase(",")) {
            sNumberToFormat = sNumberToFormat.replace(".", ",");
        }
        etNumberToFormat.setText(sNumberToFormat);

    }

}

The complete demo is here.

Answer 2

You have to programmatically set an InputFilter on your EditText by setFilters.

From the documentation:

InputFilters can be attached to Editables to constrain the changes that can be made to them.

You can even change the users input, for example by adding a decimal point which is what you want if I get you correctly.

Answer 3

I think you can use:

android:numeric="decimal"

on your EditText