Format credit card in edit text in android

Question

How to make EditText accept input in format:

4digit 4digit 4digit 4digit 

I tried Custom format edit text input android to acc

Answer 1

I think that my solution can work well whatever middle text operation or copy-paste operation.

Please see code as below,

  class BankNumberTextWatcher implements TextWatcher {
      private int previousCodeLen = 0;

      @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) {
          if (s.length() > 0) {
              String numbersOnly = s.toString().replaceAll("[^0-9]", "");
              // current code pattern miss-match, then handle cursor position and format the code
              handleEditInput(numbersOnly);
          } else {
              previousCodeLen = 0;
          }
      }

      /**
       * Handle EditText input process for credit card including insert, delete during middle position,
       * end position or copy-paste controller
       *
       * @param numbersOnly the pure number without non-digital characters
       */
      private void handleEditInput(final String numbersOnly) {
          String code = formatNumbersAsCode(numbersOnly);
          int cursorStart = etBankCardNumber.getSelectionStart();
          etBankCardNumber.removeTextChangedListener(this);
          etBankCardNumber.setText(code);
          int codeLen = code.length();
          if (cursorStart != codeLen) {
             // middle-string operation
             if (cursorStart > 0 && cursorStart % 5 == 0) {
                if (codeLen > previousCodeLen) {
                    // insert, move cursor to next
                    cursorStart++;
                } else if (codeLen < previousCodeLen) {
                    // delete, move cursor to previous
                    cursorStart--;
                }
             }
             etBankCardNumber.setSelection(cursorStart);
          } else {
             // end-string operation
             etBankCardNumber.setSelection(codeLen);
          }
          etBankCardNumber.addTextChangedListener(this);
          previousCodeLen = codeLen;
      }

      /**
       * formats credit code like 1234 1234 5123 1234
       *
       * @param s
       * @return
       */
       public String formatNumbersAsCode(CharSequence s) {
          if (TextUtils.isEmpty(s)) {
            return "";
          }
          int len = s.length();
          StringBuilder tmp = new StringBuilder();
          for (int i = 0; i < len; ++i) {
              tmp.append(s.charAt(i));
              if ((i + 1) % 4 == 0 && (i + 1) != len) {
                  tmp.append(" ");
              }
          }
          return tmp.toString();
        }
  }

Makes inputType to number for EditText to avoid other characters in the layout file.

Hope that be helpful for you.