How to add an imageview as Header and set its Width and Height

I've been trying for ages to figure this out, how to add an imageview on code and set its width to match_parent and height to wrap_content. I've tried many things but I keep getting class cast exception

    ParallaxListView pListView = (ParallaxListView) getActivity().findViewById(R.id.prods_list);

    ImageView iv = new ImageView(getActivity());
    LinearLayout.LayoutParams parms = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
    iv.setLayoutParams(parms);
    iv.setAdjustViewBounds(true);

    RequestCreator picassoRequest = Picasso.with(getActivity()).load("http://www.colonialgeneral.com/images/convenience-store.jpg").error(R.drawable.error);
    picassoRequest.into(iv);

and my fragment_list.xml

<com.nirhart.parallaxscroll.views.ParallaxListView xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/prods_list" android:layout_width="match_parent" android:layout_height="match_parent" app:parallax_factor="1.9" tools:context=".MainActivity$FragmentProds" />

nirhart / ParallaxScroll

How to add an imageview as Header and set its Width and Height #45