核心代碼如下

@Override
public void onItemSwap(int from, int target) {
    if (from < target) {
        //從上往下拖動，每滑動一個item，都將list中的item向下交換，向上滑同理。
        for (int i = from; i < target; i++) {
            Collections.swap(mData, i, i + 1);//交換數(shù)據(jù)源兩個數(shù)據(jù)的位置
        }
    } else if (from > target) {
        for (int i = from; i > target; i--) {
            Collections.swap(mData, i, i - 1);//交換數(shù)據(jù)源兩個數(shù)據(jù)的位置
        }
    }
    //刷新列表數(shù)據(jù)
    notifyItemMoved(from, target);
    notifyItemRangeChanged(Math.min(from, target), Math.abs(from - target) +1);
}