Spotify Looper: Day 11

Generalised sectionView into SegmentView to apply to all TimeUnit instances.

Created a (rudimentary) shade change to differentiate between segments.

Next step: create some kind of timeline view (sketch/design/research it first)

• For now, just have simple major and minor tick marks (don’t worry about labels) and an arrow/chevron attached to a line that stretches across the entire VStack.