Flutter Dart数组固定长度分割

将dart数组按照指定的长度分割，返回一个二维数组，实现list的split功能.

eg:
源数组：a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19]
splitList(a, 6):[[0, 1, 2, 3, 4, 5], [6, 7, 8, 9, 10, 11], [12, 13, 14, 15, 16, 17], [18, 19]]

代码如下：

static List<List<T>> splitList<T>(List<T> list, int len) {
    if (len <= 1) {
      return [list];
    }

    List<List<T>> result = List();
    int index = 1;

    while (true) {
      if (index * len < list.length) {
        List<T> temp = list.skip((index - 1) * len).take(len).toList();
        result.add(temp);
        index++;
        continue;
      }
      List<T> temp = list.skip((index - 1) * len).toList();
      result.add(temp);
      break;
    }
    return result;
  }