UIScrollView 내 각 뷰의 노출 비율을 측정하는 iOS 광고 인상 추적 라이브러리

git clone https://github.com/daangn/SushiBelt.git
cd SushiBelt/Example
pod install

let tracker = SushiBeltTracker()
tracker.delegate = someObject
tracker.dataSource = someObject
tracker.scrollView = someScrollView

extension SomeObject: SushiBeltTrackerDataSource {
  func trackingRect(_ tracker: SushiBeltTracker) -> CGRect {
    return CGRect(...)
  }
  func visibleRatioForItem(_ tracker: SushiBeltTracker, item: SushiBeltTrackerItem) -> CGFloat {
    return 0.5
  }
}

extension SomeObject: SushiBeltTrackerDelegate {
  func didEnter(_ tracker: SushiBeltTracker, item: SushiBeltTrackerItem) {
    // 노출 임계값 도달
  }
  func didExit(_ tracker: SushiBeltTracker, item: SushiBeltTrackerItem) {
    // 노출 임계값 미만으로 하강
  }
}