public class App : Application
{
    public App()
    {
        // The root page of your application
        MainPage = new MainPage
        {
            BindingContext = new MainPageViewModel()
        };
    }

    protected override void OnStart()
    {
        // Handle when your app starts
    }

    protected override void OnSleep()
    {
        // Handle when your app sleeps
    }

    protected override void OnResume()
    {
        // Handle when your app resumes
    }
}

public class MainPageViewModel
    {
        public ObservableCollection<ItemViewModel> Items { get; private set; }

        public MainPageViewModel()
        {
            Items = new ObservableCollection<ItemViewModel>()
            {
                new ItemViewModel("teste1"),
                new ItemViewModel("teste2"),
                new ItemViewModel("teste3"),
            };
        }
    }

public class ItemViewModel
    {
        public string Name { get; }

        public ItemViewModel(string name)
        {
            if (name == null) throw new ArgumentNullException(nameof(name));
            Name = name;
        }
    }

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="TestApp2.MainPage">
  <ListView ItemsSource="{Binding Items}">
    <ListView.ItemTemplate>
      <DataTemplate x:Name="ItemDataTemplate">
        <StackLayout Orientation="Horizontal">
          <Label Text="{Binding Name}" />
        </StackLayout>
      </DataTemplate>
    </ListView.ItemTemplate>
  </ListView>
</ContentPage>