swift3 - 在 Swift 3 中过滤 UICollectionview 上的结果不起作用？

Question

第一次加载 itemlist 工作正常，但过滤后集合视图没有更新。我添加了一个搜索栏并尝试过滤结果，但 UICollectionview 无法更新视图。

var resultSearchController = UISearchController()
//itemlist
var itemList = [item1, item2, item3, item4,..] 

//configured searchbar

func viewDidLoad() {
      self.resultSearchController = UISearchController(searchResultsController: nil)
      self.resultSearchController.searchResultsUpdater = self
      self.resultSearchController.searchBar.delegate = self
      self.definesPresentationContext = true
      self.resultSearchController.dimsBackgroundDuringPresentation = false
      self.resultSearchController.searchBar.placeholder = "Search for Items"
      self.resultSearchController.searchBar.searchBarStyle = UISearchBarStyle.prominent
      self.resultSearchController.searchBar.sizeToFit()
}

override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
      if resultSearchController.isActive {
            return filterSearch.count
      }
      return itemList.count
      }

override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
      var item = itemList()
      if resultSearchController.isActive {
            item = filterSearch[indexPath.row]
      } else {
            item = itemList[indexPath.row]
      }
      let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cellIdentifier", for: indexPath)
      cell.titleLabel.text = item
      return cell
}

//将项目过滤到filterSearch但集合视图没有根据过滤器更新。

func updateSearchResults(for searchController: UISearchController) {
       filterSearch = itemList.filter { itemList  in
            return temList.name.lowercased().contains(searchText.lowercased())
      }
      self.collectionView?.reloadData()
}

Answer 1

检查代码中的以下更改

var resultSearchController = UISearchController()
//itemlist
var itemList = [item1, item2, item3, item4,..] 

//configured searchbar
var issearchactive:Bool = false

func viewDidLoad() {
      self.resultSearchController = UISearchController(searchResultsController: nil)
      self.resultSearchController.searchResultsUpdater = self
      self.resultSearchController.searchBar.delegate = self
      self.definesPresentationContext = true
      self.resultSearchController.dimsBackgroundDuringPresentation = false
      self.resultSearchController.searchBar.placeholder = "Search for Items"
      self.resultSearchController.searchBar.searchBarStyle = UISearchBarStyle.prominent
      self.resultSearchController.searchBar.sizeToFit()
}

override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
      if issearchactive {
            return filterSearch.count
      }
      return itemList.count
      }

override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
      var item = itemList()
      if issearchactive {
            item = filterSearch[indexPath.row]
      } else {
            item = itemList[indexPath.row]
      }
      let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cellIdentifier", for: indexPath)
      cell.titleLabel.text = item
      return cell
}

    func updateSearchResults(searchText:String) {
           filterSearch = itemList.filter { obj  in
                return obj.name.lowercased().contains(searchText.lowercased())
          }
          self.collectionView?.reloadData()
    }


  override func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {

        issearchactive = true
        return true
    }

  override func textFieldDidEndEditing(_ textField: UITextField) {

      updateSearchResults(searchText:textfield.text)

        issearchactive = false

         }

    override func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

  updateSearchResults(searchText:textfield.text)

        return true
    }