XRecyclerView

内部有一个WrapAdapter，我们传入的adapter会在这个WrapAdapter里面

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    if (viewType == TYPE_REFRESH_HEADER) {
        // TODO: 2020/11/18 6:25 PM chenyanping onCreateViewHolder 如果我设置pullRefreshEnabled为false，mRefreshHeader为null，会异常吗
        return new SimpleViewHolder(mRefreshHeader);
    } else if (isHeaderType(viewType)) {
        return new SimpleViewHolder(getHeaderViewByType(viewType));
    } else if (viewType == TYPE_FOOTER) {
        return new SimpleViewHolder(mFootView);
    }
    return adapter.onCreateViewHolder(parent, viewType);
}

@Override
public int getItemViewType(int position) {
    int adjPosition = position - (getHeadersCount() + 1);
    if (isRefreshHeader(position)) {
        return TYPE_REFRESH_HEADER;
    }
    if (isHeader(position)) {
        position = position - 1;
        return sHeaderTypes.get(position);
    }
    if (isFooter(position)) {
        return TYPE_FOOTER;
    }
    int adapterCount;
    if (adapter != null) {
        adapterCount = adapter.getItemCount();
        if (adjPosition < adapterCount) {
            int type =  adapter.getItemViewType(adjPosition);
            if(isReservedItemViewType(type)) {
                throw new IllegalStateException("XRecyclerView require itemViewType in adapter should be less than 10000 " );
            }
            return type;
        }
    }
    return 0;
}

默认第一个item就是刷新头，所以外面用XrecyclerView时想刷新pos位置的item，需要设置pos+getHeadersCount() + 1;其中1是XrecyclerView的刷新头，getHeadersCount()是你加入的headview的个数

public boolean isRefreshHeader(int position) {
    return position == 0;
}

public boolean isHeader(int position) {
    return position >= 1 && position < mHeaderViews.size() + 1;
}

public int getHeadersCount() {
    return mHeaderViews.size();
}