Question

collectionView总是为零，我在.xib中创建它。在与collectionView的第一次交互中发生崩溃提前谢谢。

这是错误。致命错误：在解包可选值时意外发现nil

class ChannelsViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout, NSFetchedResultsControllerDelegate  {

    var managedObjectContext: NSManagedObjectContext? = AppDelegate.sharedAppDelegate().managedObjectContext;

    @IBOutlet weak var collectionView: UICollectionView!

    override func viewDidLoad() {
        super.viewDidLoad()

        self.collectionView.delegate = self
        self.collectionView.dataSource = self

        self.collectionView.registerNib(UINib(nibName:"ChannelsCollectionViewCell", bundle: nil), forCellWithReuseIdentifier: "Cell")
    }
}

Answer 1

我的问题是我没有加载笔尖。试试这个。

init() {
    super.init(nibName: "ChannelsViewController", bundle: nil)
}

required init(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
} 

override func viewDidLoad() {
    super.viewDidLoad()

    self.collectionView.delegate = self
    self.collectionView.dataSource = self

    self.collectionView.registerNib(UINib(nibName:"ChannelsCollectionViewCell", bundle: nil), forCellWithReuseIdentifier: "Cell")
}

在.xib中创建的UICollectionView是nil Swift

1 个答案: