TreeViewControl.Nodes Property

Gets the collection of root nodes.

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 TreeListNodeCollection Nodes { get; }

VB.NET

Public ReadOnly Property Nodes As TreeListNodeCollection

Property Value

Type	Description
TreeListNodeCollection	The collection of root nodes.

Remarks

You can use the Nodes property to create an unbound tree without a data source:

XAML

<dxg:TreeViewControl AutoExpandAllNodes="True">
    <dxg:TreeViewControl.Nodes>
        <dxg:TreeListNode Content="Root Node 1">
            <dxg:TreeListNode.Nodes>
                <dxg:TreeListNode Content="Level 1">
                    <dxg:TreeListNode.Nodes>
                        <dxg:TreeListNode Content="Level 2"/>
                    </dxg:TreeListNode.Nodes>
                </dxg:TreeListNode>
            </dxg:TreeListNode.Nodes>
        </dxg:TreeListNode>
        <dxg:TreeListNode Content="Root Node 2">
            <dxg:TreeListNode.Nodes>
                <dxg:TreeListNode Content="Level 1"/>
            </dxg:TreeListNode.Nodes>
        </dxg:TreeListNode>
    </dxg:TreeViewControl.Nodes>
</dxg:TreeViewControl>

Specify the TreeViewFieldName property to display data in the TreeViewControl if you set an object as a node’s content.

Iterate Through Nodes

Create a new instance of the TreeListNodeIterator class to iterate through the nodes. You can specify a start node or a collection of nodes, along with whether to process only visible nodes.

Note

If you specified a collection of nodes, the Node Iterator starts to process nodes from the first node in the specified collection.

The following code sample iterates through all visible nodes to expand nodes that have more than three child nodes.

XAML

<dxg:TreeViewControl x:Name="treeview"
                     Loaded="treeview_Loaded"
                     ... />

C#

void SmartExpandNodes(int minChildCount) {
    foreach (DevExpress.Xpf.Grid.TreeListNode node in new DevExpress.Xpf.Grid.TreeListNodeIterator(treeview.Nodes, true)) {
        node.IsExpanded = node.Nodes.Count >= minChildCount;
    }
}
void treeview_Loaded(object sender, RoutedEventArgs e) {
    SmartExpandNodes(3);
}

VB.NET

Private Sub SmartExpandNodes(ByVal minChildCount As Integer)
    For Each node As DevExpress.Xpf.Grid.TreeListNode In New DevExpress.Xpf.Grid.TreeListNodeIterator(treeview.Nodes, True)
        node.IsExpanded = node.Nodes.Count >= minChildCount
    Next
End Sub

Private Sub treeview_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
    SmartExpandNodes(3)
End Sub