Question

I need to display a tree bound to this kind of hierarchical objects:

public class Node
{
    public string Name
    public List<Connector> Connector;
}

public class Connector
{
    public string Name
    public List<Node> TrueChildren;
}

so the actual children of a node are in the other object.

Cant make TreeView template to work with it. Seems like I need circular templates which is impossible in WPF. I feel like I am missing something obvious.

Answer 1

This is not necessarily circular, it is only circular if the Connector.Children contain a reference to a node higher up on the current node path (and even that should be possible to handle somehow using virtualization).

Normally you just need to create two HierarchicalDataTemplates in the resources of the TreeView without any x:Key but the DataType set to the respective type.

<TreeView.Resources>
    <HierarchicalDataTemplate DataType="{x:Type local:Node}"
                              ItemsSource="{Binding Connector}">
        <TextBlock Text="{Binding Name}"/>
    </HierarchicalDataTemplate>

    <HierarchicalDataTemplate DataType="{x:Type local:Connector}"
                              ItemsSource="{Binding TrueChildren}">
        <TextBlock Text="{Binding Name}"/>
    </HierarchicalDataTemplate>
<TreeView.Resources>

(Using x:Type in the DataType is important, if you want to know why read the property reference)