Setting ViewModel on Fragment used in a MvxItemTemplate - android-fragments

Question

I have looked at "Down at Android Fragments" and the samples and they show the use of a single fragment in a view. In that view you Find the fragment and set its' ViewModel
We do this in a few places, like so
// Expand the patient banner
var myFragment = (MyFragment)SupportFragmentManager.FindFragmentById(Resource.Id.banner);
this.vm = (MyViewModel)this.ViewModel;
myFragment.ViewModel = this.vm;
That is fine. What I do not know how to do is set the ViewModel on a Fragment when that Fragment is used in a List's MvxItemTemplate.
For example a bound MvxListView that has an MvxItemTemplate set to this axml file
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:local="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
local:MvxBind="Click ClickCommand">
<fragment
class="MyComp.MyDept.Droid.Views.ItemFragment"
android:id="#+id/ItemFragment"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
How do I set the correct Item ViewModel for the fragment in each of the ListView's items?

Answer 1

The simplest way would be to do it in your adapter. When the list containing the items calls to GetBindableView, you'll have access to the dataContext and templateId which spawned the creation of the cell in the first place, so you can set them accordingly there, after pulling the fragment directly out of the view with a simple FindFragmentById.
So, something approximately like this should do fine for you:
protected override View GetBindableView (View convertView, object dataContext, int templateId)
{
var view = base.GetBindableView (convertView, dataContext, templateId);
var frag = (this.Context as Activity).FragmentManager.FindFragmentById<MvxFragment>(<YourDroidNamespace>.Resource.Id.ItemFragment); // Better to pass in a fragment manager instance in the constructor
frag.DataContext = dataContext;
return view;
}
First, get the view where the fragment is. Second, get the fragment manager and do a FindFragmentById on it to find your particular fragment within the view. Finally, set the DataContext and return it.