GridControl.GroupRowCollapsing Event

Occurs when a group row is about to be collapsed, allowing cancellation of the action.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v14.2.dll

Declaration

C#

public event RowAllowEventHandler GroupRowCollapsing

VB.NET

Public Event GroupRowCollapsing As RowAllowEventHandler

Event Data

The GroupRowCollapsing event's handler receives an argument of the RowAllowEventArgs type. The following properties provide information specific to this event:

Property	Description
Allow	Gets or sets whether the operation is allowed.
Handled	Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route. Inherited from RoutedEventArgs.
OriginalSource	Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs.
RoutedEvent	Gets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs.
Row	Gets the processed row. Inherited from RowEventArgs.
RowHandle	Gets the processed row's handle. Inherited from RowEventArgs.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.

Remarks

The GroupRowCollapsing event is raised before a group row is collapsed by an end-user or in code, allowing you to cancel this action. The group row is identified by its handle via the RowEventArgs.RowHandle property. To prevent the group row from being collapsed, set the event parameter's RowAllowEventArgs.Allow parameter to false.

Group rows can be collapsed recursively using the GridViewBase.CollapseFocusedRow method overload with the recursive parameter set to true. In this instance, the GroupRowCollapsing event is raised only once (for the row passed as this method's parameter). This event isn't raised for nesting group rows.

The GridControl.CollapseAllGroups method allows you to collapse all group rows. In this instance, the GroupRowCollapsing event is raised only once. The event parameter's RowEventArgs.RowHandle property returns an invalid row handle (DataControlBase.InvalidRowHandle).

After the group row has been collapsed, the GridControl.GroupRowCollapsed event is raised.

To learn more, see Expanding and Collapsing Group Rows.