ios - 如何在 CollectionViewCell 中设置元素的框架？

Question

我有一个看起来像这样的自定义单元类:

class CollectionViewCell: UICollectionViewCell {

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

    var textLabel: UILabel = UILabel()
    var buttonView: UIButton!
    var id: String = String()
    override init(frame: CGRect) {
        super.init(frame: frame)



        let textFrame = CGRect(x: buttonView.center.x - self.frame.width/2, y: 90, width: frame.size.width, height: frame.size.height/3)
        textLabel = UILabel(frame: textFrame)
        textLabel.font = UIFont.systemFontOfSize(UIFont.smallSystemFontSize())
        textLabel.textAlignment = .Center
        contentView.addSubview(textLabel)



buttonView = UIButton.buttonWithType(UIButtonType.System) as! UIButton
            buttonView.frame = CGRect(x: frame.width / 2 - frame.width * 0.4, y: 0 + textLabel.frame.size.height, width: frame.size.width * 0.8, height:  frame.size.height * 0.8 )

            contentView.addSubview(buttonView)           

        }
    }

我使单元格出队的函数看起来像这样:

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
        switch collectionView{
        case collectionViewOne!:
            let cell = collectionView.dequeueReusableCellWithReuseIdentifier("CollectionViewDetailCell", forIndexPath: indexPath) as! CollectionViewDetailCell
            cell.backgroundColor = UIColor.whiteColor()
            cellHeightOne = cell.frame.height
            cell.productLabel.text = "\(array[indexPath.row].name)"
            cell.textLabel.numberOfLines = 0

            let myText = NSString(format: self.array[indexPath.row].description)

            let paragraphStyle = NSMutableParagraphStyle() as NSMutableParagraphStyle
            paragraphStyle.alignment = NSTextAlignment.Justified
            let attributes: NSDictionary = [NSFontAttributeName: UIFont.systemFontOfSize(12), NSBaselineOffsetAttributeName: 0, NSParagraphStyleAttributeName: paragraphStyle, NSForegroundColorAttributeName: UIColor.grayColor()]
            let attributedText = NSAttributedString(string: myText as String, attributes: attributes as [NSObject : AnyObject])

            cell.textLabel.attributedText = attributedText
            cell.textLabel.sizeToFit()
            cell.contentView.addSubview(cell.textLabel)


            return cell

我想让我的标签文本高度将按钮向下移动，但没有任何反应，我还尝试找出高度并将其发送到单元格，例如: cell.textHeigth = textHeigth，并在其中使用textHeigth buttonView.frame = CGRect(x: frame.width/2 - frame.width * 0.4, y: 0 + textHeigth, width: frame.size.width , height: frame.size.height * 0.8) 但后来我得到一些变量为 nil 的错误，但我尝试打印该变量并且在将它发送到 customClass 之前它不是 nil

Answer 1

实现下面的委托(delegate)方法来设置 Collection View 单元格的宽度和高度

-(CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
     return CGSizeMake(width,height);
 }