How to implement Pull to refresh [Programatic way = not XAML]

Hey guys I am totally new to Xamarin and C# and I need your help on how to implement the Pull to refresh in programatic fashion. I searched whole internet for some tutorial on this but i didnt find anything...

So I have Content Page where I creates the ListView like this:

    public ListView CreteListFellows() {
        var listFellows = new ListView (){
            IsPullToRefreshEnabled = true,
            HasUnevenRows = true,
            Header = new Label(){
                Text = "Fellows at work",
                FontSize = 22
            }
        };      
        listFellows.ItemTemplate = new DataTemplate (typeof(FellowItemCell));

        return listFellows;
    }

Later I inserts this view to the page. Could somebody show me how to add the Pull to refresh feature to this? I know that I have to implement RefreshCommand and IsRefreshing but I dont know how...

THX very much for your help...