.NET MAUI CollectionView Sorting
The CollectionView control allows you to sort the visualized data. To configure the Sorting feature, add different SortDescriptors to the SortDescriptors collection of the CollectionView.
Property Sort Descriptor
You can sort the data by a property value from the class that defines your business items. The PropertySortDescriptor exposes the following properties:
-
PropertyName—Defines the string name of the property that is used to retrieve the key to sort by. -
SortOrder—Specifies sort order to ascending or descending.
The following example demonstrates how to define the PropertySortDescriptor.
1. Define the RadCollectionView in XAML:
<telerik:RadCollectionView x:Name="collectionView"
Grid.Row="1"
ItemsSource="{Binding Locations}"
DisplayMemberPath="City">
<telerik:RadCollectionView.BindingContext>
<local:ViewModel />
</telerik:RadCollectionView.BindingContext>
<telerik:RadCollectionView.SortDescriptors>
<telerik:PropertySortDescriptor PropertyName="City" />
</telerik:RadCollectionView.SortDescriptors>
</telerik:RadCollectionView>
2. Add the telerik namespace:
xmlns:telerik="http://schemas.telerik.com/2022/xaml/maui"
3. Create a sample DataModel:
public class DataModel : NotifyPropertyChangedBase
{
private string continent;
private string country;
private string city;
private int id;
public string Continent
{
get => this.continent;
set => this.UpdateValue(ref this.continent, value);
}
public string Country
{
get => this.country;
set => this.UpdateValue(ref this.country, value);
}
public string City
{
get => this.city;
set => this.UpdateValue(ref this.city, value);
}
public int Id
{
get => this.id;
set => this.UpdateValue(ref this.id, value);
}
}
4. Define the ViewModel class:
public class ViewModel : NotifyPropertyChangedBase
{
public ViewModel()
{
this.Locations = new ObservableCollection<DataModel>
{
new DataModel { Continent = "Europe", Country = "Austria", City = "Graz", Id = 1 },
new DataModel { Continent = "Europe", Country = "Austria", City = "Innsbruck", Id = 2 },
new DataModel { Continent = "Europe", Country = "Austria", City = "Ratz", Id = 3 },
new DataModel { Continent = "Europe", Country = "Austria", City = "Vienna", Id = 4 },
new DataModel { Continent = "Europe", Country = "Belgium", City = "Antwerp", Id = 5 },
new DataModel { Continent = "Europe", Country = "Belgium", City = "Charleroi", Id = 6 },
new DataModel { Continent = "Europe", Country = "Belgium", City = "Schaffen", Id = 7 },
new DataModel { Continent = "Europe", Country = "Denmark", City = "Copenhagen", Id = 8 },
new DataModel { Continent = "Europe", Country = "Denmark", City = "Odense", Id = 9 },
new DataModel { Continent = "Europe", Country = "France", City = "Nice", Id = 10 },
new DataModel { Continent = "Europe", Country = "France", City = "Paris", Id = 11 },
new DataModel { Continent = "Europe", Country = "Germany", City = "Baden-Baden", Id = 12 },
new DataModel { Continent = "Europe", Country = "Germany", City = "Berlin", Id = 13 },
new DataModel { Continent = "Europe", Country = "Germany", City = "Hamburg", Id = 14 },
new DataModel { Continent = "Europe", Country = "Germany", City = "Munich", Id = 15 },
new DataModel { Continent = "Europe", Country = "Germany", City = "Nuremberg", Id = 16 },
new DataModel { Continent = "Europe", Country = "Italy", City = "Bari", Id = 17 },
new DataModel { Continent = "Europe", Country = "Italy", City = "Rome", Id = 18 },
new DataModel { Continent = "Europe", Country = "Netherlands", City = "Amsterdam", Id = 19 },
new DataModel { Continent = "Europe", Country = "Netherlands", City = "Eindhoven", Id = 20 },
new DataModel { Continent = "Europe", Country = "Netherlands", City = "Rotterdam", Id = 21 },
new DataModel { Continent = "Europe", Country = "Portugal", City = "Lisbon", Id = 22 },
new DataModel { Continent = "Europe", Country = "Portugal", City = "Porto", Id = 23 },
new DataModel { Continent = "Europe", Country = "Spain", City = "Barcelona", Id = 24 },
new DataModel { Continent = "Europe", Country = "Spain", City = "Madrid", Id = 25 },
new DataModel { Continent = "Europe", Country = "United Kingdom", City = "London", Id = 26 },
new DataModel { Continent = "Europe", Country = "United Kingdom", City = "Manchester", Id = 27 },
new DataModel { Continent = "North America", Country = "United States", City = "New York", Id = 28 },
new DataModel { Continent = "North America", Country = "United States", City = "Los Angeles", Id = 29 },
new DataModel { Continent = "North America", Country = "United States", City = "Chicago", Id = 30 },
new DataModel { Continent = "North America", Country = "United States", City = "Boston", Id = 31 },
new DataModel { Continent = "North America", Country = "United States", City = "San Francisco", Id = 32 },
new DataModel { Continent = "North America", Country = "Canada", City = "Toronto", Id = 33 },
new DataModel { Continent = "North America", Country = "Canada", City = "Vancouver", Id = 34 },
new DataModel { Continent = "North America", Country = "Canada", City = "Ottawa", Id = 35 },
new DataModel { Continent = "South America", Country = "Brazil", City = "Rio de Janeiro", Id = 36 },
new DataModel { Continent = "South America", Country = "Brazil", City = "Sao Paulo", Id = 37 },
new DataModel { Continent = "South America", Country = "Brazil", City = "Salvador", Id = 38 },
new DataModel { Continent = "South America", Country = "Argentina", City = "Buenos Aires", Id = 39 },
new DataModel { Continent = "South America", Country = "Peru", City = "Lima", Id = 40 },
new DataModel { Continent = "South America", Country = "Peru", City = "Cusco", Id = 41 },
new DataModel { Continent = "South America", Country = "Colombia", City = "Bogota", Id = 42 },
new DataModel { Continent = "South America", Country = "Bolivia", City = "La Paz", Id = 43 },
new DataModel { Continent = "South America", Country = "Venezuela", City = "Caracas", Id = 44 },
new DataModel { Continent = "South America", Country = "Chile", City = "Santiago", Id = 45 },
new DataModel { Continent = "Asia", Country = "China", City = "Hong Kong", Id = 46 },
new DataModel { Continent = "Asia", Country = "China", City = "Shanghai", Id = 47 },
new DataModel { Continent = "Asia", Country = "China", City = "Macau", Id = 48 },
new DataModel { Continent = "Asia", Country = "India", City = "Delhi", Id = 49 },
new DataModel { Continent = "Asia", Country = "India", City = "Hyderabad", Id = 50 },
new DataModel { Continent = "Asia", Country = "Japan", City = "Tokyo", Id = 51 },
new DataModel { Continent = "Asia", Country = "Japan", City = "Osaka", Id = 52 },
new DataModel { Continent = "Asia", Country = "Japan", City = "Kyoto", Id = 53 },
new DataModel { Continent = "Asia", Country = "Vietnam", City = "Ho Chi Minh", Id = 54 },
new DataModel { Continent = "Asia", Country = "Vietnam", City = "Hanoi", Id = 55 },
new DataModel { Continent = "Asia", Country = "Thailand", City = "Bangkok", Id = 56 },
new DataModel { Continent = "Asia", Country = "Thailand", City = "Phuket", Id = 57 },
new DataModel { Continent = "Africa", Country = "Nigeria", City = "Lagos", Id = 58 },
new DataModel { Continent = "Africa", Country = "Egypt", City = "Cairo", Id = 59 },
new DataModel { Continent = "Africa", Country = "Algeria", City = "Algiers", Id = 60 },
new DataModel { Continent = "Oceania", Country = "Australia", City = "Sydney", Id = 61 },
new DataModel { Continent = "Oceania", Country = "Australia", City = "Melbourne", Id = 62 },
new DataModel { Continent = "Oceania", Country = "Australia", City = "Canberra", Id = 63 },
new DataModel { Continent = "Oceania", Country = "New Zealand", City = "Auckland", Id = 64 },
new DataModel { Continent = "Oceania", Country = "New Zealand", City = "Wellington", Id = 65 },
};
}
public ObservableCollection<DataModel> Locations { get; set; }
}
This is the result:
For a runnable demo with the CollectionView Sorting example, see the SDKBrowser Demo Application and go to the CollectionView > Sorting category.
Delegate Sort Descriptor
The difference between the DelegateSortDescriptor and the PropertySortDescriptor is that the DelegateSortDescriptor sorts the data by a custom key, while the PropertySortDescriptor sorts the data by a defined key, which is a property from the model.
The DelegateSortDescriptor exposes the following properties:
-
KeyLookup—Gets or sets theIKeyLookupinstance that is used to retrieve the sort key for each data item. -
SortOrder—Gets or sets the order of the sorting (ascending or descending).
To use a DelegateSortDescriptor, create a class that implements the IKeyLookup interface which will return the key by which you want to sort. Then, add the DelegateSortDescriptor to the RadCollectionView.SortDescriptors collection and set its KeyLookUp property.