How do I disable Floating GroupedHeader in Xamarin Forms iOS

I have a ListView with IsGroupingEnabled set to True. But the native behavior in iOS offers a floating Header.
Is there a way to disable the floating Headers when I scroll down the list? I want it to be fixed and is scrolling just like any cell. I prefer to customize it through CustomRenderer though I just don't know where to start.

<ListView.Header>
....
</ListView.Header>
<ListView.GroupHeaderTemplate>

....

</ListView.ItemTemplate>