static SearchBar List<Map<String,dynamic>>

TextEditingController searchCountry = TextEditingController();

  List<Map<String, dynamic>> allCountry = [];
  @override
  void initState() {
    super.initState();
    allCountry = CountryPick().countries;
  }

  void searchCountryName(String enteredKeyword) {
    List<Map<String, dynamic>> results = [];
    if (enteredKeyword.isEmpty) {
      // if the search field is empty or only contains white-space, we'll display all users
      results = CountryPick().countries;
    } else {
      results = CountryPick()
          .countries
          .where((country) => country["english_name"]
              .toLowerCase()
              .contains(enteredKeyword.toLowerCase()))
          .toList();
      // we use the toLowerCase() method to make it case-insensitive
    }

    // Refresh the UI
    setState(() {
      allCountry = results;
    });
  }