GridControl.ExpandMasterRow(Int32, DetailDescriptorBase) Method

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

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v20.2.dll

NuGet Packages: DevExpress.WindowsDesktop.Wpf.Grid.Core, 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*	Optional. 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 sample shows you a few members that allow expanding and collapsing master rows. Keyboard presses are processed to allow the CTRL+* shortcut to toggle the currently focused master row’s state. There are also two buttons - one allowing expansion of all master rows, and another that collapses details for all but the focused row.

The following members are 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.

View Example

MainWindow.xaml.vb

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 groupo row is focused
    If Not view.IsFocusedView OrElse view.FocusedRowHandle < 0 Then
        Return
    End If

    ' 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 buttonExpandAll_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    For i As Integer = 0 To gridControl1.VisibleRowCount - 1
        Dim rowHandle = gridControl1.GetRowHandleByVisibleIndex(i)
        gridControl1.ExpandMasterRow(rowHandle)
    Next i
End Sub
Private Sub buttonCollapseAllButThis_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    If tableView1.FocusedRowHandle >= 0 Then
        gridControl1.ExpandMasterRow(tableView1.FocusedRowHandle)
    End If
    For i As Integer = 0 To gridControl1.VisibleRowCount - 1
        Dim rowHandle As Integer = gridControl1.GetRowHandleByVisibleIndex(i)
        If rowHandle <> tableView1.FocusedRowHandle Then
            gridControl1.CollapseMasterRow(rowHandle)
        End If
    Next i
End Sub

MainWindow.xaml.cs

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 groupo 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;
    }
}
private void buttonExpandAll_Click(object sender, RoutedEventArgs e)
{
    for (int i = 0; i < gridControl1.VisibleRowCount; i++)
    {
        var rowHandle = gridControl1.GetRowHandleByVisibleIndex(i);
        gridControl1.ExpandMasterRow(rowHandle);
    }
}
private void buttonCollapseAllButThis_Click(object sender, RoutedEventArgs e)
{
    if (tableView1.FocusedRowHandle >= 0)
        gridControl1.ExpandMasterRow(tableView1.FocusedRowHandle);
    for (int i = 0; i < gridControl1.VisibleRowCount; i++)
    {
        int rowHandle = gridControl1.GetRowHandleByVisibleIndex(i);
        if (rowHandle != tableView1.FocusedRowHandle)
            gridControl1.CollapseMasterRow(rowHandle);
    }
}

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#

how-to-preserve-the-dxgrid-for-wpf-view-state-e4222/CS/SaveWpfGridState/RowStateHelper.cs#L102

    var datarow = gridControl.DataController.GetRow(0);
    gridControl.ExpandMasterRow(GetRowHandleByKey(key));
}

VB.NET

how-to-preserve-the-dxgrid-for-wpf-view-state-e4222/VB/SaveWpfGridState/RowStateHelper.vb#L103

    Dim datarow = gridControl.DataController.GetRow(0)
    gridControl.ExpandMasterRow(GetRowHandleByKey(key))
Next key

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)