private IExpandable getExpandableItem(int position) {
        T item = getItem(position);
        if (isExpandable(item)) {
            return (IExpandable) item;
        } else {
            return null;
        }
    }
Collapse an expandable item that has been expanded..

@param position the position of the item, which includes the header layout count.
@return the number of subItems collapsed.
common/src/main/java/com/sxjs/common/base/baseadapter/BaseQuickAdapter.java