How to change space between rows in FlexboxLayoutManager?

Question

I'm using FlexboxLayoutManager.

How to change space between rows, and space between items on the first row?

class FlexboxLayoutManagerImpl(context: Context, flexDirection: Int) :
    FlexboxLayoutManager(context, flexDirection) {

    override fun generateLayoutParams(lp: ViewGroup.LayoutParams): RecyclerView.LayoutParams {
        return LayoutParams(lp)
    }
}

And call from my adapter:

contentParent.getChildAt(i).setOnClickListener(v1 -> {
     FlexboxLayoutManagerImpl flexboxLayoutManager = new FlexboxLayoutManagerImpl(context, FlexDirection.ROW);
     holder.recycleListView.setLayoutManager(flexboxLayoutManager);
});