为什么我需要在集合视图单元更新之前先上下滚动？

Question

我正在尝试使用DECLARE @id varchar(10)='u3' SELECT Id, Subject, CASE WHEN (',' + UsersWhoLiked + ',') LIKE '%,'+@id+',%' THEN 1 ELSE 0 END Liked FROM Post 创建一个类别列表，因为我们可以看到有一个棕色圆圈实际上是CollectionView（可设计的背景视图）。

我想将背景颜色从棕色更新为随机颜色。但是随机颜色仅在我向上滚动并向下滚动UIView后显示，就像这里的.gif文件一样：http://g.recordit.co/BxRf26Uw2t.gif

向下滚动之前，颜色仍然是棕色的

向上和向下滚动后，颜色会更新，但有些项目仍然是棕色，如下所示：

这是我的CollectionView

的代码

ViewController

这是import UIKit import ChameleonFramework class FacilitiesVC: UIViewController { @IBOutlet weak var collectionVIew: UICollectionView! struct StoryBoard { // Collection View static let indoorFacilitiesCategoryCellIdentifier = "indoorFacilitiesCell" static let numberOfColumnsPerRow : CGFloat = 3.0 static let inset: CGFloat = 10.0 static let spacing: CGFloat = 8.0 static let lineSpacing: CGFloat = 8.0 //segue Identifiers } var indoorFacilitiesCategoryData = [FacilitiesCategory]() var outdoorFacilitiesCategoryData = [FacilitiesCategory]() override func viewDidLoad() { super.viewDidLoad() getIndoorOutdoorFacilitiesData() } } extension FacilitiesVC { func getIndoorOutdoorFacilitiesData() { let facilitiesData = FacilitiesCategoryLibrary.fetchFacilitiesCategory() // distinguishing between indoor and outdoor data for facData in facilitiesData { if facData.type == "Indoor Facility" { indoorFacilitiesCategoryData.append(facData) } else { outdoorFacilitiesCategoryData.append(facData) } } } } extension FacilitiesVC : UICollectionViewDataSource { // MARK: - UICollectionViewDataSource func numberOfSections(in collectionView: UICollectionView) -> Int { return 1 } func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return indoorFacilitiesCategoryData.count } func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView.dequeueReusableCell(withReuseIdentifier: StoryBoard.indoorFacilitiesCategoryCellIdentifier, for: indexPath) as! IndoorFacilitiesCell cell.indoorFacilitiesCategoryData = indoorFacilitiesCategoryData[indexPath.item] cell.designableBackgroundView.backgroundColor = RandomFlatColor() cell.layer.borderColor = UIColor.lightGray.cgColor cell.layer.borderWidth = 1 return cell } }

的代码

CollectionViewCell

这里出了什么问题？我该怎么做才能解决这个问题？