集合视图平铺

Question

我正在尝试使用包含2列图像的滚动集合视图。最后的图像将具有不同的高度，但宽度相同，只能垂直占据屏幕的一半，但正如您所看到的那样，黑色空间的图像很多。

这是代码。

import UIKit

类ViewController：UIViewController，UICollectionViewDelegate，UICollectionViewDataSource {

let screenSize: CGRect = UIScreen.mainScreen().bounds
@IBOutlet var collectionView: UICollectionView!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    if let layout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout {
        let itemWidth = CGFloat(Int(view.bounds.width / 3.0))
        let itemHeight = layout.itemSize.height
        layout.itemSize = CGSize(width: itemWidth, height: itemHeight)
        layout.invalidateLayout()
    }


}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

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

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    collectionView.registerClass(ImageCell.self, forCellWithReuseIdentifier: "Cell")
    return 10
}

}

对于细胞本身：

import Foundation
import UIKit

class ImageCell: UICollectionViewCell{

var imageView: UIImageView!


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

}

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)

    imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: frame.size.width, height: frame.size.height))
    imageView.contentMode = UIViewContentMode.ScaleAspectFit
    imageView.image = UIImage(named: "defaultImage.jpg")
    contentView.addSubview(imageView)

    //fatalError("init(coder:) has not been implemented")
}
}

Answer 1

使用此委托功能

    func collectionView(_ collectionView: UICollectionView,
                          layout collectionViewLayout: UICollectionViewLayout,
          sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {

            CGSize screenSize=UIScreen.mainScreen().bounds.size

        return CGSizeMake(screenSize.width/2, yourheighteOfImage);
        }

    func collectionView(_ collectionView: UICollectionView,
                                      layoutcollectionViewLayout:UICollectionViewLayout,minimumInteritemSpacingForSectionAtIndex section: Int) -> CGFloat {
       return 0.0
    }