Spinner with Checkbox and Textboxes recognize, when Item Checked State is change, in the Adapter

i have in my RecylcerViewAdapter a Spinner, with a SpinnerAdapter, because i have Checkbox - TextView, with dynamic Items.

I want to recognize in my RecylcerViewAdapter, when a SpinnerItem checked, to do things in my RecyclerViewAdapter. The View works fine.

How i add:

AdditionSpinnerAdapter adapter = new AdditionSpinnerAdapter(context, 0, categoryProductAddition.Product_Additions);
vh.AdditionSpinner.Adapter = adapter;

My SpinnerAdapter

namespace AndroidRegFirstApp.Adapter
{
public class AdditionSpinnerAdapter : ArrayAdapter<ProductAddition>
{
    private Context mContext;
    private List<ProductAddition> additions;
    
    public AdditionSpinnerAdapter(Context context, int resource, List<ProductAddition> objects) :base (context, resource, objects)
    {
        this.mContext = context;
        this.additions = objects;
    }

    public override View GetDropDownView(int position, View convertView, ViewGroup parent)
    {
        return this.GetCustomView(position, convertView, parent);
    }

    public override View GetView(int position, View convertView, ViewGroup parent)
    {
        return this.GetCustomView(position, convertView, parent);
    }

    public View GetCustomView(int position, View convertView, ViewGroup parent)
    {
        LayoutInflater inflater = LayoutInflater.From(mContext);
        convertView = inflater.Inflate(Resource.Layout.additionSpinnerItem, null);

        TextView AdditionText = convertView.FindViewById<TextView>(Resource.Id.additionText);
        CheckBox AdditionSelected = convertView.FindViewById<CheckBox>(Resource.Id.additionSelected);

        AdditionText.Text = additions[position].Product_Addition_Name;
        AdditionSelected.Checked = additions[position].Product_Addition_Selected;

        AdditionSelected.Tag = position;

        if (position == 0)
        {
            AdditionSelected.Visibility = ViewStates.Gone;
        }

        AdditionSelected.SetOnCheckedChangeListener(new Interface.OnCheckedListener(additions));

        return convertView;
    }
}

}

My OnCheckedListener:

public OnCheckedListener(List<ProductAddition> list)
    {
        this.additions = list;
    }

    public void OnCheckedChanged(CompoundButton buttonView, bool isChecked)
    {
        int position = (int)buttonView.Tag;
        this.additions[position].Product_Addition_Selected = isChecked;
    }

Now i want to when the OnCheckedChanged is change the state, that a methode in my RecylcerViewAdapter calls.