protected override void OnNavigatedTo(NavigationEventArgs e)
{
// first option is to use newly created class (ClientGroup) and method + XAML
// this.DataContext = ClientLoader.LoadClientGroups();
// second option: if we don`t have ClientGroup class
// we can use LINQ to group items as below. We also don`t need to use
//ItemsPath in XAML of our CollectionViewSource + adjsut HeaderTemplate
ObservableCollection <Client> clients = ClientLoader.LoadClients();
this.DataContext = clients.OrderBy(f => f.Name).GroupBy(f => f.Name[0]); // we are ordering by name and grouping by the first character of the name
// LINQ will create IGrouping object
//************* The ICollectionViewGroup *************
// to understand to what kind of properties we are binding to from XAML
// public interface ICollectionView : IObservable<object>, IList<object>, IEnumerable<object>
// {
// ....
// IObservableVector<object> CollectionGroups { get; }
// }
//public interface ICollectionViewGroup
//{
// object Group { get; }
// IObservableVector<object> GroupItems { get; }
//}
}
protected override void OnNavigatedTo(NavigationEventArgs e)
{
this.DataContext = ClientLoader.LoadClients();
}