GridControl.EndGrouping Event

Occurs after the grouping operation has been completed. This is a routed event.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v22.2.dll

NuGet Package: DevExpress.Wpf.Grid.Core

Declaration

C#

public event RoutedEventHandler EndGrouping

VB.NET

Public Event EndGrouping As RoutedEventHandler

Event Data

The EndGrouping event's data class is RoutedEventArgs. The following properties provide information specific to this event:

Property	Description
Handled	Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route.
OriginalSource	Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class.
RoutedEvent	Gets or sets the RoutedEvent associated with this RoutedEventArgs instance.
Source	Gets or sets a reference to the object that raised the event.

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.
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.

Remarks

Each time the grid’s data is grouped or ungrouped by a column, the grid does the following:

• Fires the GridControl.StartGrouping event.
• Performs data grouping.
• Fires the GridControl.EndGrouping event.

Since data grouping requires sorting, the GridControl.StartSorting and GridControl.EndSorting events are also raised before and after grouping.

To learn more, see Grouping.

Example

The following example does not allow users to collapse the Status: Invalidated group row and expand the Status: Delivered group row.

View Example: Forbid Expand and Collapse Operations for Group Rows

XAML

<dxg:GridControl x:Name="grid" 
                 EndGrouping="OnEndGrouping"
                 GroupRowCollapsing="OnGroupRowCollapsing"
                 GroupRowCollapsed="OnGroupRowCollapsed"
                 GroupRowExpanding="OnGroupRowExpanding"
                 GroupRowExpanded="OnGroupRowExpanded">
    <dxg:GridColumn FieldName="ProductName"/>
    <dxg:GridColumn FieldName="Price"/>
    <dxg:GridColumn FieldName="Discount"/>
    <dxg:GridColumn FieldName="Status" GroupIndex="0" SortOrder="Descending"/>
    <dxg:GridControl.View>
        <dxg:TableView x:Name="view" GroupValueTemplateSelector="{StaticResource groupRowTemplateSelector}"/>
    </dxg:GridControl.View>
</dxg:GridControl>

C#

void OnEndGrouping(object sender, RoutedEventArgs e) {
    if (grid.Columns[nameof(Invoice.Status)].GroupIndex == 0) {
        var childRow = grid.FindRowByValue(grid.Columns[nameof(Invoice.Status)], InvoiceStatus.Invalidated);
        var groupRow = grid.GetParentRowHandle(childRow);
        grid.ExpandGroupRow(groupRow);

        childRow = grid.FindRowByValue(grid.Columns[nameof(Invoice.Status)], InvoiceStatus.Delivered);
        groupRow = grid.GetParentRowHandle(childRow);
        grid.CollapseGroupRow(groupRow);
    }
}


void OnGroupRowCollapsing(object sender, RowAllowEventArgs e) {
    if (e.Row != null && grid.GetGroupRowValue(e.RowHandle).Equals(InvoiceStatus.Invalidated))
        e.Allow = false;
}
void OnGroupRowCollapsed(object sender, RowEventArgs e) {
    if (e.Row == null && grid.Columns[nameof(Invoice.Status)].GroupIndex == 0) {
        var childRow = grid.FindRowByValue(grid.Columns[nameof(Invoice.Status)], InvoiceStatus.Invalidated);
        var groupRow = grid.GetParentRowHandle(childRow);
        grid.ExpandGroupRow(groupRow);
    }
}


void OnGroupRowExpanding(object sender, RowAllowEventArgs e) {
    if (e.Row != null && grid.GetGroupRowValue(e.RowHandle).Equals(InvoiceStatus.Delivered))
        e.Allow = false;
}
void OnGroupRowExpanded(object sender, RowEventArgs e) {
    if (e.Row == null && grid.Columns[nameof(Invoice.Status)].GroupIndex == 0) {
        var childRow = grid.FindRowByValue(grid.Columns[nameof(Invoice.Status)], InvoiceStatus.Delivered);
        var groupRow = grid.GetParentRowHandle(childRow);
        grid.CollapseGroupRow(groupRow);
    }
}

VB.NET

Private Sub OnEndGrouping(ByVal sender As Object, ByVal e As RoutedEventArgs)
    If Me.grid.Columns(NameOf(Invoice.Status)).GroupIndex = 0 Then
        Dim childRow = Me.grid.FindRowByValue(Me.grid.Columns(NameOf(Invoice.Status)), InvoiceStatus.Invalidated)
        Dim groupRow = Me.grid.GetParentRowHandle(childRow)
        Me.grid.ExpandGroupRow(groupRow)
        childRow = Me.grid.FindRowByValue(Me.grid.Columns(NameOf(Invoice.Status)), InvoiceStatus.Delivered)
        groupRow = Me.grid.GetParentRowHandle(childRow)
        Me.grid.CollapseGroupRow(groupRow)
    End If
End Sub

Private Sub OnGroupRowCollapsing(ByVal sender As Object, ByVal e As RowAllowEventArgs)
    If e.Row IsNot Nothing AndAlso Me.grid.GetGroupRowValue(e.RowHandle).Equals(InvoiceStatus.Invalidated) Then e.Allow = False
End Sub

Private Sub OnGroupRowCollapsed(ByVal sender As Object, ByVal e As RowEventArgs)
    If e.Row Is Nothing AndAlso Me.grid.Columns(NameOf(Invoice.Status)).GroupIndex = 0 Then
        Dim childRow = Me.grid.FindRowByValue(Me.grid.Columns(NameOf(Invoice.Status)), InvoiceStatus.Invalidated)
        Dim groupRow = Me.grid.GetParentRowHandle(childRow)
        Me.grid.ExpandGroupRow(groupRow)
    End If
End Sub

Private Sub OnGroupRowExpanding(ByVal sender As Object, ByVal e As RowAllowEventArgs)
    If e.Row IsNot Nothing AndAlso Me.grid.GetGroupRowValue(e.RowHandle).Equals(InvoiceStatus.Delivered) Then e.Allow = False
End Sub

Private Sub OnGroupRowExpanded(ByVal sender As Object, ByVal e As RowEventArgs)
    If e.Row Is Nothing AndAlso Me.grid.Columns(NameOf(Invoice.Status)).GroupIndex = 0 Then
        Dim childRow = Me.grid.FindRowByValue(Me.grid.Columns(NameOf(Invoice.Status)), InvoiceStatus.Delivered)
        Dim groupRow = Me.grid.GetParentRowHandle(childRow)
        Me.grid.CollapseGroupRow(groupRow)
    End If
End Sub

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the EndGrouping event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

XAML

wpf-grid-prevent-expand-collapse-operations-for-group-rows/CS/Forbid_Expand_Collapse/MainWindow.xaml#L19

<dxg:GridControl x:Name="grid"
                 EndGrouping="OnEndGrouping"
                 GroupRowCollapsing="OnGroupRowCollapsing"