what do I need to do to get the glassy navigation bar buttons?

To achieve the glassy appearance for navigation bar buttons in your UIKit app, you need to adopt the new design system introduced in iOS 26, which includes the Liquid Glass material. Here are the steps you should follow:

1. Assign Bar Button Items: Assign all bar button items directly to the navigation items. This will give you the default system behavior where the system automatically separates them into visual groups, each sharing a glass background by default.

2. Use Fixed Space Items: To further break items into separate groups, use a fixed space item. This helps in separating buttons like the Share button from others, as shown in the example from the session.

3. Customize Tint Color: Bar buttons use label color by default to improve legibility. If you need to communicate information through color, specify a different tint color. For instance, you can update a button to use System orange as the tint color.

4. Prominent Style: Set the style to prominent for buttons that need to stand out. This style tints the glass using the accent color, which is perfect for displaying state or emphasizing an important action.

For more detailed guidance, you can refer to the session Build a UIKit app with the new design (07:19) where navigation and toolbars are discussed in detail.