public void setCurrentItem(int item) {
        mPopulatePending = false;
        setCurrentItemInternal(item, !mFirstLayout, false);
    }
Set the currently selected page. If the ViewPager has already been through its first
layout with its current adapter there will be a smooth animated transition between
the current item and the specified item.

@param item Item index to select
dkplayer-sample/src/main/java/xyz/doikki/dkplayer/widget/VerticalViewPager.java