Grouping

RadListView provides you with the functionality to programmatically group its data. This can be achieved through adding group descriptors to the RadListView.GroupDescriptors collection.

There are two type of descriptors:

• PropertyGroupDescriptor : You can group the data by a property value from the class that defines your items.

This descriptor exposes the following properties:

• PropertyName : Gets or sets the string name of the property you want to group by.
• SortOrder : Changes the sort order in each group to Ascending or Descending.

• DelegateGroupDescriptor : This descriptor enables you to group by a custom key(e.g. some complex expression combining two or more properties) instead of being limited by the value of a single property of your item. This descriptor exposes the following properties:
• KeyLookup : Gets or sets the IKeyLookup instance used to retrieve the group key for each data item.
• SortOrder : Changes the sort order in each group to Ascending or Descending.

Example

The example below demonstrates how you can use DelegateGroupDescriptor.

First, add the RadListView definition:

<dataControls:RadListView ItemsSource="{Binding}">
    <dataControls:RadListView.Resources>
        <local:Key x:Key="key" />
    </dataControls:RadListView.Resources>
    <dataControls:RadListView.ItemTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding Name}" />
        </DataTemplate>
    </dataControls:RadListView.ItemTemplate>
    <dataControls:RadListView.GroupDescriptors>
        <dataCore:DelegateGroupDescriptor SortOrder="Descending" KeyLookup="{StaticResource key}" />
    </dataControls:RadListView.GroupDescriptors>
</dataControls:RadListView>

Add the needed namespaces:

xmlns:dataControls="using:Telerik.UI.Xaml.Controls.Data"
xmlns:dataCore="using:Telerik.Data.Core"

Here is the code-behind logic:

List<Item> list = new List<Item>();
for (int i = 0; i < 10; i++)
{
    list.Add(new Item { Id = i, Name = "Mr." + i });
}
this.DataContext = list;

public class Item
{
    public string Name { get; set; }
    public double Id { get; set; }
}

public class Key : IKeyLookup
{
    public object GetKey(object instance)
    {
        return (instance as Item).Id % 2;
    }
}