ios - 图像未加载到 UITableViewCell Swift 中

Question

1. 这是对 TableView 中的每个单元格重复执行的函数。正如您所看到的，我在名为 Product 的对象内传递了一个图像数组(称为图像集)。ProductImages 是一个 Product 数组。在这个对象中，我们有名称、价格和图像集。

   func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
   
       let cell = tableView.dequeueReusableCellWithIdentifier("productCell", forIndexPath: indexPath) as! ProductHomeCell
   
       cell.productName.text = productImages[indexPath.row].name
       cell.productPrice.text = "\(productImages[indexPath.row].price)"
   
       //cell.PageImages contains Array of Images
       cell.pageImages = productImages[indexPath.row].imageSet
   
       return cell
   }
   

2. 现在我们将设置自定义 UITableViewCell，其中将加载并显示所看到的产品信息。注意我使用 ScrollView 滚动图像。(我从 stackoverflow 中的一个问题中获取了代码)PageImages 是应该传递 imageSet 的变量。

   var pageImages: [UIImage] = []
   
   var pageViews: [UIImageView?] = []
   var pageControl : UIPageControl = UIPageControl(frame: CGRectMake(60, 300, 195, 5))
   
   
   override func awakeFromNib() {
   
   
       super.awakeFromNib()
       scrollView.delegate = self
       pageControl = UIPageControl(frame: CGRectMake(230, 14, 107, 37))
   
       //PageImages should be loaded.
       let pageCount = pageImages.count
       self.pageControl.numberOfPages = pageCount
       configurePageControl()
       pageControl.enabled = false
   
       // 3
       for _ in 0..<pageCount {
           pageViews.append(nil)
       }
   
       // 4
       let pagesScrollViewSize = scrollView.frame.size
   
   
       scrollView.contentSize = CGSize(width: pagesScrollViewSize.width * CGFloat(pageImages.count),
           height: pagesScrollViewSize.height)
   
   
       loadVisiblePages()
   
   }
   
   func loadPage(page: Int) {
       if page < 0 || page >= pageImages.count {
           // If it's outside the range of what you have to display, then do nothing
           return
       }
   
       // 1
       if let pageView = pageViews[page] {
           // Do nothing. The view is already loaded.
       } else {
           // 2
           var frame = scrollView.bounds
           frame.origin.x = frame.size.width * CGFloat(page)
           frame.origin.y = 0.0
   
           // 3
           let newPageView = UIImageView(image: pageImages[page])
           // let newPageView = UIImageView(image: imageC)
   
           newPageView.contentMode = .ScaleAspectFit
           newPageView.frame = frame
           scrollView.addSubview(newPageView)
   
           // 4
           pageViews[page] = newPageView
       }
   }
   
   func loadVisiblePages() {
       // First, determine which page is currently visible
       let pageWidth = scrollView.frame.size.width
       let page = Int(floor((scrollView.contentOffset.x * 2.0 + pageWidth) / (pageWidth * 2.0)))
   
       // Work out which pages you want to load
       let firstPage = page - 1
       let lastPage = page + 1
   
       // Purge anything before the first page
       for var index = 0; index < firstPage; ++index {
           purgePage(index)
       }
   
       // Load pages in our range
       for index in firstPage...lastPage {
           loadPage(index)
       }
   
       // Purge anything after the last page
       for var index = lastPage+1; index < pageImages.count; ++index {
           purgePage(index)
       }
   }
   
   func scrollViewDidScroll(scrollView: UIScrollView) {
       // Load the pages that are now on screen
       loadVisiblePages()
   }
   
   func purgePage(page: Int) {
       if page < 0 || page >= pageImages.count{
           // If it's outside the range of what you have to display, then do         nothing
           return
       }
   
       // Remove a page from the scroll view and reset the container array
       if let pageView = pageViews[page] {
           pageView.removeFromSuperview()
           pageViews[page] = nil
       }
   }
   
   override func setSelected(selected: Bool, animated: Bool) {
       super.setSelected(selected, animated: animated)
   
       // Configure the view for the selected state
   }
   
   
   func configurePageControl() {
   
       self.pageControl.currentPage = 0
       self.pageControl.tintColor = UIColor.blackColor()
   
       self.pageControl.pageIndicatorTintColor = UIColor.lightGrayColor()
       self.pageControl.currentPageIndicatorTintColor = UIColor.blackColor()
       self.addSubview(pageControl)
   }
   
   func scrollViewDidEndDecelerating(scrollView: UIScrollView) {
       let pageNumber = round(scrollView.contentOffset.x / scrollView.frame.size.width)
       pageControl.currentPage = Int(pageNumber)
   }
   

3. 问题 - 产品名称和价格加载完美。图像没有。当我调试时，当 awakeFromNib() 运行时，PageImages 看起来是空的，但是当我在 cellForARowAtIndexPath 方法中调试时，var PageImages 会在该 indexPath.row 处加载 imageSet。谢谢

Answer 1

awakeFromNib 在 dequeue... 返回单元格之前执行，因此尝试在那里设置页面是行不通的。我见过的两种方法要么有一种显式设置单元的方法:

func setupCell(productName:String, productPrice:Double, images:[UIImage]) {
    // Do most of what you have in awakeFromNib here
}

或者在属性的 didSet 中执行此操作:

var pageImages : [UIImage] = [] {
    didSet {
        // Set up your page controller here.
    }
}