CollectionView reloadData() 奇怪的行为

Question

我想制作一个带有单元格的集合视图，您可以在其中选择我的小游戏的颜色。因此，您可以在不同的主题之间进行选择（每个主题都在一个单元格中）。如果主题被解锁（通过获得分数），模糊视图和锁定图标应该消失，并且所有可用的单元格/主题应该是可选的。我是这样实现的：

（集合 ViewController 类：）

    import UIKit
import PMSuperButton

class myCollectionViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource {

    @IBOutlet weak var backBtn: UIButton!
    
    let items = ["Default dot", "Trap your first dot", "Score 15 or less (classic)", "Score 5 or less (classic)", "Score 15 or less (hard)", "Score 25 or less (no chill)", "Score 15 or less (snake)", "Score 15 or less everywhere", "Score 10 or less everywhere", "Circle the dot 100 times", "10"]
    var preSelected = IndexPath()
    
    @IBOutlet weak var myCollectionView: UICollectionView!
    override func viewDidLoad() {
        super.viewDidLoad()
        updateUnlockedString()
        updateColor()
    }
    
    func updateColor(){
        view.backgroundColor = myColors().selected(value: selectedInstance.selectedColor).backgroundColor
    }
    func   updateUnlockedString(){
        let easyHS = UserDefaults.standard.integer(forKey: "highscoreeasy")
        let classicHS = UserDefaults.standard.integer(forKey: "highscoreclassic")
        let hardHS = UserDefaults.standard.integer(forKey: "highscorehard")
        let nochillHS = UserDefaults.standard.integer(forKey: "highscoreno chill")
        let snakeHS = UserDefaults.standard.integer(forKey: "highscoresnake")
        
        var unlockedString = ""
        
        //unimportant steps deleted

        UserDefaults.standard.set(unlockedString, forKey: "unlocked")
        
    }

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return items.count
    }
    
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! myCollectionViewCell
        if(unlockInstance.unlockedString.contains(String(indexPath.item))){
            cell.unlockedEffect()
            print("unlocked Effect")
        }
        cell.label.text = items[indexPath.item]
        cell.removeHighlight()
        if indexPath.item == selectedInstance.selectedColor{
             cell.highlightEffect()
             preSelected = IndexPath(item: indexPath.item, section: indexPath.section)
         }
        cell.setupCellFilling(playerColor: myColors().selected(value: indexPath.item).playerColor, objColor: myColors().selected(value: indexPath.item).objColor, defaultColor: myColors().selected(value: indexPath.item).defaultColor, backgroundColor: myColors().selected(value: indexPath.item).backgroundColor)
         myCollectionView = collectionView
        return cell
    }
    
    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        collectionView.allowsMultipleSelection = false
        if ((collectionView.cellForItem(at: indexPath) as! myCollectionViewCell?) != nil) && unlockInstance.unlockedString.contains(String(indexPath.item)){
            selectedInstance.selectedColor = indexPath.item
            updateColor()
            collectionView.reloadData()
        }
    }
    @IBAction func backPressed(_ sender: Any) {
        cameInstance.came = true
    }
    
}

（收集CELL类：）

    import UIKit

class myCollectionViewCell: UICollectionViewCell {
    
    @IBOutlet weak var label: UILabel!
    @IBOutlet weak var view: UIView!
    @IBOutlet weak var blurView: UIVisualEffectView!
    @IBOutlet weak var lockedBlur: UIVisualEffectView!
    @IBOutlet weak var lockedIcon: UIImageView!

    override func layoutSubviews() {
        // cell rounded section
        self.layer.cornerRadius = 15.0
        self.layer.masksToBounds = true
        
        // cell shadow section
        self.contentView.layer.cornerRadius = 15.0
        self.contentView.layer.masksToBounds = true
        self.layer.shadowColor = myColors().selected(value: selectedInstance.selectedColor).defaultColor.cgColor
        self.layer.shadowOffset = CGSize(width: 0.0, height: 0.0)
        self.layer.shadowRadius = 6.0
        self.layer.shadowOpacity = 0.4
        self.layer.cornerRadius = 15.0
        self.layer.masksToBounds = false
        self.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, cornerRadius: self.contentView.layer.cornerRadius).cgPath
        super.layoutSubviews()
    }
   

extension myCollectionViewCell{

   func highlightEffect(){
      self.layer.borderWidth = 5.0
      self.layer.borderColor = UIColor.systemGreen.cgColor
   }

   func removeHighlight(){
      self.layer.borderColor = UIColor.clear.cgColor
   }
    func unlockedEffect(){
        lockedBlur.alpha = 0
        lockedIcon.alpha = 0
    }
    func setupCellFilling(playerColor: UIColor, objColor: UIColor, defaultColor: UIColor, backgroundColor: UIColor){
        
        lockedBlur.effect = UIBlurEffect(style: .extraLight)
        blurView.effect = UIBlurEffect(style: .systemUltraThinMaterialDark)
        lockedIcon.tintColor = objColor
        view.backgroundColor = backgroundColor
  
    }

}

问题

当我打开 CollectionView (viewDidLoad) 时，一切看起来都 100% 正常！所有应锁定的单元格都显示为已锁定（lockedBlur.alpha = 0 和lockedIcon.alpha = 0）。此外，只有锁定的单元格是可选的，我可以看到绿色边框。只有选中的 Cell 有绿色边框，没错。

但是：当我选择一个单元格时，一些随机锁定的单元格会失去其模糊视图并失去其锁定图标（因此 blockedBlur 和 lockedIcon 消失）。它们仍然不可选择。有时这会影响所有单元格，有时仅会影响所有单元格，例如2.

当我选择一个单元格时，会调用 didSelectItemAt 函数。这也调用了 updateColors()，它只改变了背景并调用了神秘的 reloadData()。在我看来，reloadData() 不知何故使lockedBlur 和lockedIcon 消失了，我找不到原因....

也许有人可以帮助我..

谢谢！！

快速爱好

Answer 1

我正在开发健身应用程序，它的训练计划部分具有非常相似的 CollectionView 行为。基本上，您在完成练习时会选择某个单元格。所以我玩了很多实现选择和取消选择单元格的方法。如我所见，您缺少 CollectionViewDelegate 的选择和取消选择功能。在那里你设置不同的状态效果

这是你必须使用的功能：

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    if let cell = collectionView.cellForItem(at: indexPath) as? CustomCollectionViewCell {
        cell.showIcon()
    }
}

func collectionView(_ collectionView: UICollectionView, didDeselectItemAt indexPath: IndexPath) {
    if let cell = collectionView.cellForItem(at: indexPath) as? CustomCollectionViewCell {
        cell.hideIcon()
    }
}