GridControl.ExpandMasterRow(Int32, DetailDescriptorBase) Method

Expands the specified master row and, optionally, shows the specified Detail.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v24.2.dll

NuGet Package: DevExpress.Wpf.Grid.Core

Declaration

C#

public void ExpandMasterRow(
    int rowHandle,
    DetailDescriptorBase descriptor = null
)

VB.NET

Public Sub ExpandMasterRow(
    rowHandle As Integer,
    descriptor As DetailDescriptorBase = Nothing
)

Parameters

Name	Type	Description
rowHandle	Int32	An integer value specifying the master row by its handle. If the specified row handle is invalid, the method does nothing.

Optional Parameters

Name	Type	Default	Description
descriptor	DetailDescriptorBase	null	A DetailDescriptorBase object specifying the detail to be shown. If the specified object doesn’t represent the specified row’s detail, the method expands the first or previously visible detail, depending on whether the current row was previously expanded.

Remarks

Use this method to expand rows or switch between active Details via code. This might be useful if you want to implement custom controls that manipulate Detail views and hide default expand buttons by disabling the TableView.ShowDetailButtons option.

The ExpandMasterRow method will not have any effect if overridden by the GridControl.MasterRowExpanding event handler.

You can also expand or collapse master rows using the GridControl.CollapseMasterRow and GridControl.SetMasterRowExpanded methods. To determine the expanded state of a row and the currently visible detail, use the GridControl.MasterRowExpanded and GridControl.GetVisibleDetail members.

Example

This example demonstrates how to expand and collapse the GridControl‘s master rows in code. The example contains the following buttons:

• The Expand All button expands all master rows.
• The Collapse All button collapses all master rows.
• The Collapse All But This button collapses all master rows except for the focused row / row with the focused detail.

The CTRL+* shortcut is bound to toggle the focused master row’s expanded state.

View Example: Expand and Collapse Master Rows

The following table lists members used in this example:

Member	Description
GridControl.CollapseMasterRow	Collapses the detail section for the specified row.
GridControl.ExpandMasterRow	Expands the specified master row and, optionally, shows the specified Detail.
GridControl.IsMasterRowExpanded	Determines the specified master row’s expanded state and, optionally, the specified Detail’s visibility.
GridControl.SetMasterRowExpanded	Changes the expanded state for a specified master row and, optionally, shows a specified Detail.

XAML

<dxg:GridControl x:Name="grid" AutoGenerateColumns="AddNew" Grid.Column="0">
    <dxg:GridControl.View>
        <dxg:TableView x:Name="view" AutoWidth="True" ShowGroupPanel="False" PreviewKeyDown="TableView_KeyDown"/>
    </dxg:GridControl.View>
    <dxg:GridControl.DetailDescriptor>
        <dxg:DataControlDetailDescriptor ItemsSourcePath="Orders">
            <dxg:DataControlDetailDescriptor.DataControl>
                <dxg:GridControl AutoGenerateColumns="AddNew">
                    <dxg:GridControl.View>
                        <dxg:TableView AutoWidth="True" ShowGroupPanel="False"/>
                    </dxg:GridControl.View>
                </dxg:GridControl>
            </dxg:DataControlDetailDescriptor.DataControl>
        </dxg:DataControlDetailDescriptor>
    </dxg:GridControl.DetailDescriptor>
</dxg:GridControl>

<StackPanel Grid.Column="1" Orientation="Vertical" Margin="10,10,10,10">
    <Button Click="ExpandAll" Content="Expand All" Margin="0,10,0,0"/>
    <Button Click="CollapseAll" Content="Collapse All" Margin="0,10,0,0"/>
    <Button Click="CollapseAllButThis" Content="Collapse All But This"  Margin="0,10,0,0"/>
    <TextBlock TextWrapping="Wrap" Margin="0,30,0,0">
        Press <Bold>CTRL+*</Bold> to toggle the focused master row's expanded state.
    </TextBlock>
</StackPanel>

C#

private void TableView_KeyDown(object sender, KeyEventArgs e) {
    TableView view = sender as TableView;

    // Avoid key processing when focus is within detail views or when a group row is focused:
    if (!view.IsFocusedView || view.FocusedRowHandle < 0)
        return;

    // Process CTRL+* key combination:
    if (e.Key == Key.Multiply && ((Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control)) {
        bool finalExpandedState = !view.Grid.IsMasterRowExpanded(view.FocusedRowHandle);
        view.Grid.SetMasterRowExpanded(view.FocusedRowHandle, finalExpandedState);
        e.Handled = true;
    }
}

void ExpandAll(object sender, RoutedEventArgs e) {
    for (int i = 0; i < grid.VisibleRowCount; i++) {
        var rowHandle = grid.GetRowHandleByVisibleIndex(i);
        grid.ExpandMasterRow(rowHandle);
    }
}

void CollapseAll(object sender, RoutedEventArgs e) {
    for (int i = 0; i < grid.VisibleRowCount; i++) {
        var rowHandle = grid.GetRowHandleByVisibleIndex(i);
        grid.CollapseMasterRow(rowHandle);
    }
}

void CollapseAllButThis(object sender, RoutedEventArgs e) {
    for (int i = 0; i < grid.VisibleRowCount; i++) {
        var rowHandle = grid.GetRowHandleByVisibleIndex(i);
        var detailGrid = grid.GetVisibleDetail(rowHandle);
        if (detailGrid != null) {
            var detailView = ((GridControl)detailGrid).View;
            var focusedDetailRowHandle = ((TableView)detailView).FocusedRowHandle;
            if (focusedDetailRowHandle == DataControlBase.InvalidRowHandle && rowHandle != view.FocusedRowHandle)
                grid.CollapseMasterRow(rowHandle);
        }
    }
}

VB.NET

Private Sub TableView_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
    Dim view As TableView = TryCast(sender, TableView)
    ' Avoid key processing when focus is within detail views or when a group row is focused:
    If Not view.IsFocusedView OrElse view.FocusedRowHandle < 0 Then Return
    ' Process CTRL+* key combination:
    If e.Key = Key.Multiply AndAlso (Keyboard.Modifiers And ModifierKeys.Control) = ModifierKeys.Control Then
        Dim finalExpandedState As Boolean = Not view.Grid.IsMasterRowExpanded(view.FocusedRowHandle)
        view.Grid.SetMasterRowExpanded(view.FocusedRowHandle, finalExpandedState)
        e.Handled = True
    End If
End Sub

Private Sub ExpandAll(ByVal sender As Object, ByVal e As RoutedEventArgs)
    For i As Integer = 0 To Me.grid.VisibleRowCount - 1
        Dim rowHandle = Me.grid.GetRowHandleByVisibleIndex(i)
        Me.grid.ExpandMasterRow(rowHandle)
    Next
End Sub

Private Sub CollapseAll(ByVal sender As Object, ByVal e As RoutedEventArgs)
    For i As Integer = 0 To Me.grid.VisibleRowCount - 1
        Dim rowHandle = Me.grid.GetRowHandleByVisibleIndex(i)
        Me.grid.CollapseMasterRow(rowHandle)
    Next
End Sub

Private Sub CollapseAllButThis(ByVal sender As Object, ByVal e As RoutedEventArgs)
    For i As Integer = 0 To Me.grid.VisibleRowCount - 1
        Dim rowHandle = Me.grid.GetRowHandleByVisibleIndex(i)
        Dim detailGrid = Me.grid.GetVisibleDetail(rowHandle)
        If detailGrid IsNot Nothing Then
            Dim detailView = CType(detailGrid, GridControl).View
            Dim focusedDetailRowHandle = CType(detailView, TableView).FocusedRowHandle
            If focusedDetailRowHandle = DataControlBase.InvalidRowHandle AndAlso rowHandle <> Me.view.FocusedRowHandle Then Me.grid.CollapseMasterRow(rowHandle)
        End If
    Next
End Sub

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the ExpandMasterRow(Int32, DetailDescriptorBase) method.

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.

C#

wpf-data-grid-bind-master-and-detail-focused-rows-to-viewmodel-properties/CS/UpdateMasterDetailFocusedRowBehavior.cs#L132

    return;
visualGrid.ExpandMasterRow(rowHandle);
tempGrid = (GridControl)visualGrid.GetDetail(rowHandle);

VB.NET

wpf-data-grid-bind-master-and-detail-focused-rows-to-viewmodel-properties/VB/UpdateMasterDetailFocusedRowBehavior.vb#L124

If newCurrentItem Is Nothing Then Return
visualGrid.ExpandMasterRow(rowHandle)
tempGrid = CType(visualGrid.GetDetail(rowHandle), GridControl)

wpf-data-grid-display-detail-content-in-tabs/VB/WpfApplication18/MainWindow.xaml.vb#L14

    Me.grid.ItemsSource = Employees.GetEmployees()
    AddHandler Me.grid.Loaded, Sub(d, e) TryCast(d, GridControl)?.ExpandMasterRow(0)
End Sub

wpf-data-grid-display-chart-control-in-grid-details/VB/WpfApplication19/MainWindow.xaml.vb#L15

    Me.grid.ItemsSource = Employees.GetEmployees()
    AddHandler Me.grid.Loaded, Sub(d, e) TryCast(d, GridControl)?.ExpandMasterRow(0)
End Sub

wpf-data-grid-create-master-detail-grid-in-code/VB/MasterDetailInCode/MainWindow.xaml.vb#L13

AddDetails(gridControl)
AddHandler gridControl.Loaded, Sub(d, e) TryCast(d, GridControl)?.ExpandMasterRow(0)
Me.grid.Children.Add(gridControl)

wpf-data-grid-display-custom-content-in-grid-details/VB/WpfApplication18/MainWindow.xaml.vb#L14

    Me.grid.ItemsSource = Employees.GetEmployees()
    AddHandler Me.grid.Loaded, Sub(d, e) TryCast(d, GridControl)?.ExpandMasterRow(0)
End Sub