17.16 Exploring the User Interface Layout Hierarchy
Xcode also provides an option to break the user interface layout out into a rotatable 3D view that shows how the view hierarchy for a user interface is constructed. This can be particularly useful for identifying situations where one view instance is obscured by another appearing on top of it or a layout is not appearing as intended. This is also useful for learning how SwiftUI works behind the scenes to construct a SwiftUI layout, if only to appreciate how much work SwiftUI is saving us from having to do.
To access the view hierarchy in this mode, begin by previewing the view in debug mode as illustrated in Figure 17-12 above. Once the preview is live, click on the Debug View Hierarchy button indicated in Figure 17-28:
Figure 17-28
Once activated, a 3D “exploded” view of the layout will appear. Clicking and dragging within the view will rotate the hierarchy allowing the layers of views that make up the...