public void removeFooterView(View footer) {
        if (getFooterLayoutCount() == 0) return;

        mFooterLayout.removeView(footer);
        if (mFooterLayout.getChildCount() == 0) {
            int position = getFooterViewPosition();
            if (position != -1) {
                notifyItemRemoved(position);
            }
        }
    }
remove footer view from mFooterLayout,
When the child count of mFooterLayout is 0, mFooterLayout will be set to null.

@param footer
common/src/main/java/com/sxjs/common/base/baseadapter/BaseQuickAdapter.java