One of the main advantages to using a UWP control is that controls are "lookless" with a fully customizable user interface. Just as you design your own user interface (UI), or look and feel, for UWP applications, you can provide your own UI for data managed by TreeView for UWP. Extensible Application Markup Language (XAML; pronounced "Zammel"), an XML-based declarative language, offers a simple approach to designing your UI without having to write code.
Accessing Templates
You can access templates in Microsoft Expression Blend by selecting the C1TreeView control and, in the menu, selecting Edit Template. Select Edit a Copy to create an editable copy of the current template or Create Empty, to create a new blank template.
Once you've created a new template, the template will appear in the Objects and Timeline window. Note that you can use the Template property to customize the template.
Note: If you create a new template through the menu, the template will automatically be linked to that template's property. If you manually create a template in XAML you will have to link the appropriate template property to the template you've created.
Additional Templates
In addition to the default template, the C1TreeView control includes a few additional templates. These additional templates can also be accessed in Microsoft Expression Blend – in Blend select the C1TreeView control and, in the menu, select Edit Additional Templates. Choose a template, and select Create Empty: