Another solution instead of tableView.reloadData()

Question

I am calling batch updates(begin/end updates) on a tableView using this code:

  let oldImageSet = Set(oldImageArray)
  let newImageSet = Set(self.images)
  let m         


        

Answer 1

You should just apply what you're doing with rows to sections which means changing IndexPaths to IndexSets. IndexSet can be initialized with an array of Ints where each Int represents a corresponding section.

  let oldImageSet = Set(oldImageArray)
  let newImageSet = Set(self.images)
  let addedImages = newImageSet.subtracting(oldImageSet)
  // map each image to the section equivalent to its index in `self.images`
  let addedImageSections = Array(missingImages).map{ self.images.indexOf($0)! }
  let addedImageIndexSet = IndexSet(addedImageSections)

  // repeat above process but in reverse to find images that have been removed
  let removedImages = oldImageSet.subtracting(newImageSet)
  let removedImageSections = Array(removedImages).map{ oldImageArray.index(of: $0)! }
  let removedImageIndexSet = IndexSet(removedImageSections)

  self.tableView.beginUpdates()

  // if images have been added insert new sections 
  if !addedImageIndexSet.isEmpty {
        self.tableView.insertSections(addedImageIndexSet, with: .top)
  }

  // if images have been deleted remove sections    
  if !removedImageIndexSet.isEmpty {
        self.tableView.deleteSections(removedImageIndexSet, with: .none)
  }
  self.tableView.endUpdates()