限制EditText不能输入中文的监听器

/**
 * edittext输入监听，不允许输入中文
 */
public class NoChineseTextWatcher implements TextWatcher {
    final String reg = "[^[\u4E00-\u9FA5]]";//正则表达式，非中文
    private boolean isNotMatch = false;
    private EditText editText;

    public NoChineseTextWatcher(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) {
        String str = s.toString();
        if (!TextUtils.isEmpty(str)){
            char[] chars = str.toCharArray();
            for (int i = 0; i < str.length(); i++) {
                String aChar = String.valueOf(chars[i]);
                if (!aChar.matches(reg)) {
                    isNotMatch = true;
                }
            }
            if (isNotMatch){
                ToastUtil.showToast("密码不能设置中文，请重新设置！");
                editText.setText("");
                isNotMatch = false;
            }
        }else {
            isNotMatch = false;
        }
    }
}