编译器说我不符合UICollectionViewDelegate;与实际使用冲突

Question

我相信我跟随UICollectionViewDataSource，但编译器却说不然。
我错过了什么？

import Foundation
import UIKit

class InviteFriendsViewController:UIViewController, UICollectionViewDataSource, UICollectionViewDelegate {

    @IBOutlet weak var collectionView: UICollectionView!

    @IBAction func navButtonAction(sender: UIBarButtonItem) {

    }

    @IBAction func segmentedControlAction(sender: UISegmentedControl) {
    }

    // -----------------------------------------------------------------------------------------------------
// MARK: UICollectionViewDataSource

    func collectionView(collectionView: UICollectionView, section: Int) -> Int {
        return 1
    }

    func collectionView(collectionView: UICollectionView, indexPath: NSIndexPath) -> UICollectionViewCell {
        let cell: AnyObject = collectionView.dequeueReusableCellWithReuseIdentifier("InviteFriendsVC", forIndexPath:indexPath)
        return cell as UICollectionViewCell
    }
}

我有两（2）个func，涵盖了所需的API ......但是我得到了这个编译错误。
为什么呢？

Answer 1

您必须以这种方式声明您的功能：

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int{

    return 1
}

// The cell that is returned must be retrieved from a call to -dequeueReusableCellWithReuseIdentifier:forIndexPath:
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell{

    let cell: AnyObject = collectionView.dequeueReusableCellWithReuseIdentifier("InviteFriendsVC", forIndexPath:indexPath)
    return cell as UICollectionViewCell
}

试试这可能对你有帮助。