Merge pull request #1232 from telerik/new-kb-datagrid-sorting-grouping-descending-order-1db77cef1edd4f36a340ed3491d66af4

Added new kb article datagrid-sorting-grouping-descending-order

Author: didiyordanova

knowledge-base/datagrid-sorting-grouping-descending-order.md

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+---
+title: Sorting and Grouping in Descending Order in RadDataGrid
+description: Learn how to sort and group items in the RadDataGrid for UI for .NET MAUI in descending order.
+type: how-to
+page_title: Setting Sort and Group Descriptors to Descending Order in RadDataGrid
+meta_title: Setting Sort and Group Descriptors to Descending Order in RadDataGrid
+slug: datagrid-sorting-grouping-descending-order
+tags: datagrid, ui-for-dotnet-maui, sort-descriptors, group-descriptors, descending-order
+res_type: kb
+---
+
+## Environment
+
+| Version | Product | Author | 
+| --- | --- | ---- | 
+| 11.1.0 | DataGrid for .NET MAUI | [Dobrinka Yordanova](https://www.telerik.com/blogs/author/dobrinka-yordanova) |
+
+## Description
+
+I need when the user groups the DataGrid through the U, the groups to appear in descending order. Currently, the items are sorted by `FirstContactDate` in descending order, but when grouped, the grouping defaults to ascending order. The goal is to allow users to see the latest entries grouped by `FirstContactDate` in descending order.
+
+This knowledge base article also answers the following questions:
+- How to sort and group items in descending order in DataGrid?
+- How to set group descriptors to descending order in Telerik DataGrid for .NET MAUI?
+- How to change group descriptor order dynamically during grouping?
+
+## Solution
+
+To achieve sorting and grouping in descending order, follow one of the approaches below:
+
+### Option 1: Set Sort and Group Descriptors Explicitly
+
+Define both `SortDescriptors` and `GroupDescriptors` with the desired `SortOrder` in the XAML configuration:
+
+```xaml
+<telerik:RadDataGrid.GroupDescriptors>
+    <telerik:PropertyGroupDescriptor PropertyName="FirstContactDate" SortOrder="Descending" />
+</telerik:RadDataGrid.GroupDescriptors>
+
+<telerik:RadDataGrid.SortDescriptors>
+    <telerik:PropertySortDescriptor PropertyName="FirstContactDate" SortOrder="Descending" />
+</telerik:RadDataGrid.SortDescriptors>
+```
+
+### Option 2: Change Group Sort Order at Runtime
+
+Use the `GroupDescriptors.CollectionChanged` event to dynamically update the `SortOrder` of the group descriptor when a column is grouped. Example:
+
+```csharp
+public partial class MainPage : ContentPage
+{
+    public MainPage()
+    {
+        InitializeComponent();
+        BindingContext = new RegistrationViewModel();
+
+        this.dataGrid.GroupDescriptors.CollectionChanged += GroupDescriptors_CollectionChanged;
+    }
+
+    private void GroupDescriptors_CollectionChanged(object? sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
+    {
+        if (e.Action != NotifyCollectionChangedAction.Add)
+            return;
+        
+        var groupDescriptor = e.NewItems[0] as GroupDescriptorBase;
+        if (groupDescriptor != null)
+        {
+            groupDescriptor.SortOrder = SortOrder.Descending;
+        }
+    }
+}
+```
+
+## See Also
+
+- [DataGrid Documentation](https://docs.telerik.com/devtools/maui/controls/datagrid/overview)