How to create searching in dart language

 Searching in Dart 

//BinarySearch using mixin class

mixin BinarySearch{

  int binarySearch(list, element) {

  int start = 0;

  int end = list.length - 1;

 // int i = 0;

  while (start <= end) {

    int mid = ((start + end) / 2).floor();

    if (list[mid] == element) {

      return mid;

    }

    if (list[mid] < element) {

      start = mid + 1;

    } else {

      end = mid - 1;

    }

  }

  return -1;

}

}

//This is  Binary Search Method

binarySearch(List<int> arr, int userValue, int min, int max) {

  if (max >= min) {

    print('min $min');

    print('max $max');

    int mid = ((max + min) / 2).floor();

    if (userValue == arr[mid]) {

      print('your item is at index: ${mid}');

    } else if (userValue > arr[mid]) {

      binarySearch(arr, userValue, mid + 1, max);

    } else {

      binarySearch(arr, userValue, min, mid - 1);

    }

  }

  return null;

}