DataGridView.GroupCollapsing Event
Occurs before a group of rows is collapsed.
Namespace: DevExpress.Maui.DataGrid
Assembly: DevExpress.Maui.DataGrid.dll
NuGet Package: DevExpress.Maui.DataGrid
Declaration
public event EventHandler<CancelRowEventArgs> GroupCollapsing
Event Data
The GroupCollapsing event's data class is CancelRowEventArgs. The following properties provide information specific to this event:
Property | Description |
---|---|
Cancel | Gets or sets a value indicating whether the event should be canceled. Inherited from CancelEventArgs. |
RowHandle | Returns the handle of the processed row. |
Remarks
The GroupCollapsing
event is raised before a group of data rows is collapsed from UI or code (CollapseGroupRow. You can handle this event and set its parameter’s Cancel property to true
to prevent a group from being collapsed.
When you call the CollapseAllGroups method, the GroupCollapsing
event is raised for each group.
After the group row has been collapsed, the GroupCollapsed event is raised.
Example
The example below shows how to prevent the “Today” group in the grid from being collapsed. To obtain the group value, the DataGridView.GetGroupValue method is used.
<dxg:DataGridView x:Name="grid" ItemsSource="{Binding Orders}"
GroupCollapsing="grid_GroupCollapsing">
<dxg:DataGridView.Columns>
<!--...-->
<dxg:DateColumn x:Name="DateColumn"
FieldName="Date"
DisplayFormat="d"
GroupInterval="DateRange"
IsGrouped="True"/>
<!--...-->
</dxg:DataGridView.Columns>
</dxg:DataGridView>
private void grid_GroupCollapsing(object sender, RowAllowEventArgs e) {
string groupValue = (string)grid.GetGroupValue(e.RowHandle);
if (groupValue == "Today") e.Allow = false;
}