Hi Teddy,

You're absolutely right in your observations. Initially, the property used for grouping is null, and even after it's set to a non-null value, the group remains blank. However, this happens because, in the original sample, INotifyPropertyChanged wasn't triggered when the grouped data changed.

Here’s the relevant part of the original code:

public SecurityType? SecurityType => Security?.SecurityType;

And here’s the updated version that properly raises OnPropertyChanged:

// NOTE: Raises PropertyChanged.
public SecurityType? SecurityType
{
    get => _securityType;
    set => SetProperty(ref _securityType, value);
}

Additionally, for the grouping engine to react to OnPropertyChanged, the ApplyDataOperationsOnPropertyChange setting must not be False. One approach is to bind this property to a value in your ViewModel and enable it when the grouping property is updated and data is initialized.

All these adjustments have been made in the updated sample project. With these changes, the engine now correctly regenerates the groups in response to property changes. Based on this, the issue was marked as declined.

That said, if there's something I’ve missed feel free to let me know - we can absolutely reopen the issue if needed.

Regards,
Nasko
Progress Telerik

Hi Teddy,

Upon further investigation, the behavior was found to be related to the application logic rather than an issue with the control itself. Therefore, the item status has been updated to Declined.

Regards,
Nasko
Progress Telerik