How to set android:orientation="horizontal" programmatically in RelativeLayout?

Question

How to set android:orientation="horizontal" programatically in RelativeLayout like so:

<RelativeLayout
                android:id="@+id/ID"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal" >

</RelativeLayout>

This is what I have so far:

RelativeLayout rLayout = new RelativeLayout(getActivity());
LayoutParams layoutParams;
layoutParams = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
rLayout.setLayoutParams(layoutParams);