Anchors are a way we can refer to the absolute positioning of a view at any level in the view tree. This is useful when you want to have one view surround, underline, or point to another element in the view tree. Combined with GeometryReader, you don't need to worry about converting between coordinate systems like you do in UIKit. Anchors work much like other preferences, with some small differences. In this episode we will build a bar graph view, then use anchors to animate an indicator on the selected item in the graph.
This is a companion discussion topic for the original entry at https://nsscreencast.com/episodes/442-swiftui-anchors-preferences