TextWatcher for formatting SSN as XXX-XX-XXXX

SSNFormattingTextWatcher.java

import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;

public class SSNFormattingTextWatcher implements TextWatcher {
    private EditText mEditText;
    private boolean mShouldDeleteSpace;

    public SSNFormattingTextWatcher(EditText editText) {
        mEditText = editText;
    }

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

    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        if (start > 0) {
            CharSequence charDeleted = s.subSequence(start - 1, start);
            mShouldDeleteSpace = "-".equals(charDeleted.toString());
        }
    }

    public void afterTextChanged(Editable editable) {
        mEditText.removeTextChangedListener(this);

        int cursorPosition = mEditText.getSelectionStart();
        String withSpaces = formatText(editable);
        mEditText.setText(withSpaces);

        mEditText.setSelection(cursorPosition + (withSpaces.length() - editable.length()));

        if (mShouldDeleteSpace) {
            //  userNameET.setSelection(userNameET.getSelectionStart() - 1);
            mShouldDeleteSpace = false;
        }

        mEditText.addTextChangedListener(this);
    }

    private String formatText(CharSequence text) {
        StringBuilder formatted = new StringBuilder();
        if (text.length() == 4 || text.length() == 7) {
            if (!mShouldDeleteSpace) {
                formatted.append(text.subSequence(0, text.length() - 1) + "-" + text.charAt(text.length() - 1));
            } else {
                formatted.append(text.subSequence(0, text.length() - 1));
            }
        } else {
            formatted.append(text);
        }
        return formatted.toString();
    }
}