The vertical scrollbar of RadGridView disappears in some cases when the last parent item is expanded and then collapsed. The issue reproduces only with the Flat GroupRenderMode and when UseLayoutRounding property is set to True.

The workaround is to avoid setting the UseLayoutRounding property to True.

This issue manifests when RadGridView loaded some columns first (which are working) and then add more columns. The additional columns cannot paste values in their cells.

To work this around, mark the new columns as auto generated and call one of the internal methods.

newColumn.IsAutoGenerated = true;
this.gridView.Columns.Add(newColumn);

var collectionViewPropInfo = this.gridView.Items.GetType().GetProperty("CollectionView", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
var qcv = (QueryableCollectionView)collectionViewPropInfo.GetValue(this.gridView.Items);
var methodInfo = qcv.GetType().GetMethod("OnElementTypeChanged", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
methodInfo.Invoke(qcv, new object[0]);

NullReferenceException occurs when the the automation peers creation for the rows goes over 10,000 peers (the MaxCachedPeersSize setting of the GridViewDataControlAutomationPeer). The exception occurs only when the 'record' modifier is used in the class definition. For example:

public record class MyClass(int Id)
{
}

The exception stacktrace is:

System.NullReferenceException: 'Object reference not set to an instance of an object.'
peer was null.
Telerik.Windows.Controls.GridView.dll!Telerik.Windows.Automation.Peers.GridViewDataControlAutomationPeer.ClearPeer(Telerik.Windows.Automation.Peers.DataItemAutomationPeer peer)   Telerik.Windows.Controls.GridView.dll!Telerik.Windows.Automation.Peers.GridViewDataControlAutomationPeer.GetOrCreateItemPeer(object item, int index) Line 288 C#  Telerik.Windows.Controls.GridView.dll!Telerik.Windows.Automation.Peers.GridViewRowAutomationPeer.FindDataItemAutomationPeer(System.Collections.Generic.List<System.Windows.Automation.Peers.AutomationPeer> childPeers) Telerik.Windows.Controls.GridView.dll!Telerik.Windows.Automation.Peers.GridViewRowAutomationPeer.GetChildrenCore() 

.

To work this around use the "class" modifier instead of "record". For example, instead of:

public record class MyClass(int Id)
{
}

Use:

public class MyClass
{
    public int Id { get; set; } 
}

 Or alternatively, increase the MaxCachedPeersSize value.

InvalidOperationException in FilteringViewModel.ClearFilters()

1. Scroll to near the bottom of grid.
2. Refresh the Grid, populating it with less items.
3. Should see mostly blank grid besides for bottom row.
4. If you scroll any the rows show back up.

When DragElementAction="ExtendedSelect" in GridView is set, there is a problem with the deselecting
behaviour. Ctrl + click no longer deselects the row.

The problem should be resolved with lib version 2015.3.1019.

GridView ColumnGroup Header does not refresh when bound to view model

IsReorderable of a column is not respected when ReorderColumnsMode is different than the default one

Fixed with LIB version 2014.1.317.

Change AlternateRowBackground (runtime) has only effects after scrolling in grid or after rebinding it.

When KeyboardNavigation.TabNavigation is set to Once, RadGridView does not lose the focus after the second time it's focused.

GridViewColumn's IsVisible Binding breaks when you create an instance of a usercontrol.

HeaderCheckBoxStyle of GridViewSelectColumn returns TextBlock as Header in Office2013 theme

Currently, when a user selects multiple rows, but skips a few, and then copies, the data in the Clipboard will look as if the selected rows were in an uninterrupted sequence. Unselected columns, on the other hand, leave a "hole" in the clipboard data. This

Add Option to disable autoBring into View the focused RadGridView unit.

Enable multiple rows to be edited in a RadGridView at once.

We currently do this based on creating multiple row selection and editing the last selected cell and then applying the value (if valid to do so) across the selection.