public void setOnHeaderLongClickListener(OnHeaderLongClickListener listener) {
        if (!isLongClickable()) {
            setLongClickable(true);
        }
        mOnHeaderLongClickListener = listener;
    }
If set to true, headers will ignore horizontal padding.

@param b if true, horizontal padding is ignored by headers
Library/src/com/tonicartos/widget/stickygridheaders/StickyGridHeadersGridView.java