GridControl.ExpandMasterRow(Int32, DetailDescriptorBase) Method

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

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v20.1.dll

Declaration

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

Examples

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.
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
See Also