导航标题视图中的UICollectionView对选择无响应

如何解决导航标题视图中的UICollectionView对选择无响应

我在UINavigationItem的标题视图中有一个UICollectionView作为菜单。我无法在集合视图中选择项目。如果我将UICollectionView放置在导航项之外并放入视图控制器，则一切都会按预期进行。

UIViewController

let menuView = HomeMenuView()

override func viewDidLoad() {
    navigationItem.titleView = menuView
    menuView.delegate = self
}

HomeMenuView（UICollectionView）

class HomeMenuView: UIView,UICollectionViewDelegate,UICollectionViewDataSource,UICollectionViewDelegateFlowLayout {

var sections = ["Recent","Following"]

var delegate: HomeMenuDelegate!
var selectedIndex = 0

var collectionView: UICollectionView!

override init(frame: CGRect) {
    super.init(frame: frame)
    create()
}

func create() {
    let layout = UICollectionViewFlowLayout()
    layout.scrollDirection = .horizontal
    layout.minimumLineSpacing = 0
    layout.minimumInteritemSpacing = 0
    layout.sectionInset = UIEdgeInsets(top: 0,left: 0,bottom: 0,right: 0)
    collectionView = UICollectionView(frame: .zero,collectionViewLayout: layout)
    addSubview(collectionView)
    collectionView.anchor(top: nil,left: nil,bottom: nil,right: nil,paddingTop: 0,paddingLeft: 0,paddingBottom: 0,paddingRight: 0,width: UIScreen.main.bounds.width/2,height: 30)
    collectionView.center(x: centerXAnchor,y: centerYAnchor)
    collectionView.backgroundColor = .clear
    collectionView.isUserInteractionEnabled = true
    collectionView.clipsToBounds = true
    collectionView.allowsSelection = true
    collectionView.delegate = self
    collectionView.dataSource = self
    collectionView.register(HomeMenuCell.self,forCellWithReuseIdentifier: "cellID")
}

func collectionView(_ collectionView: UICollectionView,numberOfItemsInSection section: Int) -> Int {
    return sections.count
}

func collectionView(_ collectionView: UICollectionView,cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cellID",for: indexPath) as! HomeMenuCell
    cell.title = sections[indexPath.row]
    cell.isSelected = selectedIndex == indexPath.row
    return cell
}

func collectionView(_ collectionView: UICollectionView,didSelectItemAt indexPath: IndexPath) {
    guard let currentCell = collectionView.cellForItem(at: IndexPath(row: selectedIndex,section: 0)) as? HomeMenuCell else { return }
    guard let newCell = collectionView.cellForItem(at: indexPath) as? HomeMenuCell else { return }
    currentCell.isSelected = false
    newCell.isSelected = true
    selectedIndex = indexPath.row
    delegate.didSelectSection(at: indexPath.row)
}

func collectionView(_ collectionView: UICollectionView,layout collectionViewLayout: UICollectionViewLayout,sizeForItemAt indexPath: IndexPath) -> CGSize {
    return CGSize(width: (collectionView.frame.width)/CGFloat(sections.count),height: collectionView.frame.height)
}

override func layoutSubviews() {
    super.layoutSubviews()
    collectionView.layer.cornerRadius = collectionView.bounds.height/2
}

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

解决方法

无法选择您的收藏夹视图单元格，因为您的收藏夹视图超出其超级视图的范围。

按如下所示更改create()函数的中间部分（您没有包括“约束帮助器”，因此我使用了标准约束语法）：

    addSubview(collectionView)
    
    collectionView.translatesAutoresizingMaskIntoConstraints = false
    NSLayoutConstraint.activate([

        collectionView.topAnchor.constraint(equalTo: topAnchor,constant: 0.0),collectionView.leadingAnchor.constraint(equalTo: leadingAnchor,collectionView.trailingAnchor.constraint(equalTo: trailingAnchor,collectionView.bottomAnchor.constraint(equalTo: bottomAnchor,collectionView.widthAnchor.constraint(equalToConstant: UIScreen.main.bounds.width * 0.5),collectionView.heightAnchor.constraint(equalToConstant: 30.0),])
    
    //collectionView.anchor(top: nil,left: nil,bottom: nil,right: nil,paddingTop: 0,paddingLeft: 0,paddingBottom: 0,paddingRight: 0,width: UIScreen.main.bounds.width/2,height: 30)
    //collectionView.center(x: centerXAnchor,y: centerYAnchor)
    
    collectionView.backgroundColor = .clear