wpf-devexpress-dot-xpf-dot-grid-dot-gridcontrol-dd35da0e.md
Enables you to specify whether a master row may be expanded.
Namespace : DevExpress.Xpf.Grid
Assembly : DevExpress.Xpf.Grid.v25.2.dll
NuGet Package : DevExpress.Wpf.Grid.Core
public event RowAllowEventHandler MasterRowExpanding
Public Event MasterRowExpanding As RowAllowEventHandler
The MasterRowExpanding event's data class is RowAllowEventArgs. 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. |
The event data class exposes the following methods:
| Method | Description |
|---|---|
| InvokeEventHandler(Delegate, Object) | When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation. Inherited from RoutedEventArgs. |
| OnSetSource(Object) | When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes. Inherited from RoutedEventArgs. |
The MasterRowExpanding event fires when a master row is about to be expanded. This happens when an end-user tries to expand a row and when you call an appropriate method, such as GridControl.ExpandMasterRow. By using the event’s arguments you can identify the row being collapsed and determine whether to allow this operation.
Once a row has been expanded, the grid raises the GridControl.MasterRowExpanded event.
See Also
ExpandMasterRow(Int32, DetailDescriptorBase)
CollapseMasterRow(Int32, DetailDescriptorBase)