fetchCategories method Null safety

Future<Categories> fetchCategories()

API call to get the categories.

Implementation

static Future<Categories> fetchCategories() async {
  final response = await http.get(Uri.parse('https://opentdb.com/api_category.php'));
  if (response.statusCode == 200) {
    return Categories.fromJson(jsonDecode(response.body));
  } else {
    throw Exception('Failed to load questions');
  }
}