Android Edittext with auto detection of credit card type

Question

I am dealing with payment option in android, By give an option to make a payment with credit card, some of the users may mistakenly choosing different credit card type for some

Answer 1

From the help of above answers and suggestion i have achieved the result,

Here is the solution:

Create a function for regex making

public static ArrayList listOfPattern()
{
    ArrayList listOfPattern=new ArrayList();

    String ptVisa = "^4[0-9]$";

    listOfPattern.add(ptVisa);

    String ptMasterCard = "^5[1-5]$";

    listOfPattern.add(ptMasterCard);

    String ptDiscover = "^6(?:011|5[0-9]{2})$";

    listOfPattern.add(ptDiscover);

    String ptAmeExp = "^3[47]$";

    listOfPattern.add(ptAmeExp);

    return listOfPattern;
}

Integer[] imageArray = { R.drawable.visa, R.drawable.master, R.drawable.disnet, R.drawable.ae };

use this below code in addTextChangedListener

creditcardnumberedittext.addTextChangedListener(new TextWatcher()
    {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count)
        {
            String ccNum = s.toString();

            if(ccNum.length()>=2)
            {
                for (int i = 0; i < listOfPattern.size(); i++)
                {
                    if (ccNum.substring(0, 2).matches(listOfPattern.get(i)))
                    {
                        creditcardnumberedittext.setCompoundDrawablesWithIntrinsicBounds(0, 0, imageArray[i], 0);

                        cardtype = String.valueOf(i);
                    }
                }
            }

        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after)
        {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable s)
        {               

            if (!creditcardnumberedittext.getText().toString().equalsIgnoreCase(""))
            {
                for (int i = 0; i < listOfPattern.size(); i++)
                {
                    if (creditcardnumberedittext.getText().toString().matches(listOfPattern.get(i)))
                    {
                        creditcardnumberedittext.setCompoundDrawablesWithIntrinsicBounds(0, 0, imageArray[i], 0);

                        cardtype = String.valueOf(i);
                    }
                }
            }
            else
            {
                creditcardnumberedittext.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.allcards, 0);
            }
        }
    });

Thanks..