How to Automatically add thousand separators as number is input in EditText

This sample app deconstructs formatting numbers clearly.

To summarize the link above, use a TextWatcher and in the afterTextChanged() method format the EditText view with the following logic:

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

    try {
        String originalString = s.toString();

        Long longval;
        if (originalString.contains(",")) {
            originalString = originalString.replaceAll(",", "");
        }
        longval = Long.parseLong(originalString);

        DecimalFormat formatter = (DecimalFormat) NumberFormat.getInstance(Locale.US);
        formatter.applyPattern("#,###,###,###");
        String formattedString = formatter.format(longval);

        //setting text after format to EditText
        editText.setText(formattedString);
        editText.setSelection(editText.getText().length());
    } catch (NumberFormatException nfe) {
        nfe.printStackTrace();
    }

    editText.addTextChangedListener(this);
}

You can use String.format() in a TextWatcher. The comma in the format specifier does the trick.

This does not work for floating point input. And be careful not to set an infinite loop with the TextWatcher.

public void afterTextChanged(Editable view) {
    String s = null;
    try {
        // The comma in the format specifier does the trick
        s = String.format("%,d", Long.parseLong(view.toString()));
    } catch (NumberFormatException e) {
    }
    // Set s back to the view after temporarily removing the text change listener
}

public static String doubleToStringNoDecimal(double d) {
    DecimalFormat formatter = (DecimalFormat) NumberFormat.getInstance(Locale.US);
    formatter.applyPattern("#,###");
    return formatter.format(d);
}

Even-though It's late. Intended for future visitors.

Fetures of the following codes

1. Puts thousand separator in EditText as it's text changes.

2. adds 0. Automatically when pressed period (.) At First.

3. Ignores 0 input at Beginning.

Just copy the following Class named

NumberTextWatcherForThousand which implements TextWatcher

import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import java.util.StringTokenizer;

/**
 * Created by skb on 12/14/2015.
 */
public class NumberTextWatcherForThousand implements TextWatcher {

    EditText editText;


    public NumberTextWatcherForThousand(EditText editText) {
        this.editText = editText;


    }

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

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {

    }

    @Override
    public void afterTextChanged(Editable s) {
        try
        {
            editText.removeTextChangedListener(this);
            String value = editText.getText().toString();


            if (value != null && !value.equals(""))
            {

                if(value.startsWith(".")){
                    editText.setText("0.");
                }
                if(value.startsWith("0") && !value.startsWith("0.")){
                    editText.setText("");

                }


                String str = editText.getText().toString().replaceAll(",", "");
                if (!value.equals(""))
                editText.setText(getDecimalFormattedString(str));
                editText.setSelection(editText.getText().toString().length());
            }
            editText.addTextChangedListener(this);
            return;
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
            editText.addTextChangedListener(this);
        }

    }

    public static String getDecimalFormattedString(String value)
    {
        StringTokenizer lst = new StringTokenizer(value, ".");
        String str1 = value;
        String str2 = "";
        if (lst.countTokens() > 1)
        {
            str1 = lst.nextToken();
            str2 = lst.nextToken();
        }
        String str3 = "";
        int i = 0;
        int j = -1 + str1.length();
        if (str1.charAt( -1 + str1.length()) == '.')
        {
            j--;
            str3 = ".";
        }
        for (int k = j;; k--)
        {
            if (k < 0)
            {
                if (str2.length() > 0)
                    str3 = str3 + "." + str2;
                return str3;
            }
            if (i == 3)
            {
                str3 = "," + str3;
                i = 0;
            }
            str3 = str1.charAt(k) + str3;
            i++;
        }

    }

    public static String trimCommaOfString(String string) {
//        String returnString;
        if(string.contains(",")){
            return string.replace(",","");}
        else {
            return string;
        }

    }
}

Use This Class on your EditText as follows

editText.addTextChangedListener(new NumberTextWatcherForThousand(editText));

To get the input as plain Double Text

Use the trimCommaOfString method of the same class like this

NumberTextWatcherForThousand.trimCommaOfString(editText.getText().toString())

Git