嗨,我是swift的新手,需要一些帮助,谢谢。该程序工作一次,试图再次运行然后崩溃。我调试时,这些项目在数组中,但是当我尝试显示图像时,我得到了致命的错误。
// Get Brands
func getBrand () {
// Create PFQuery
var query:PFQuery = PFQuery(className: "BrandInfo")
// Call findobjects
query.findObjectsInBackgroundWithBlock {
(objects:[AnyObject]?, error: NSError?) -> Void in
// refresh array
self.brands = [String]()
self.pics = [UIImage]()
// loop through array
for brandObject in objects! {
// get PFObjects
let brandName:String? = (brandObject as! PFObject)["Name"] as? String
if brandName != nil {
self.brands.append(brandName!)
}
let brandPicture = brandObject["Image"] as! PFFile
brandPicture.getDataInBackgroundWithBlock({ (imageData:NSData?, error:NSError?) -> Void in
if(error == nil){
let brandImage = UIImage(data: imageData!)
self.pics.append(brandImage)
println(self.pics.count)
}
})
}
// Refresh CollectionView
self.collectionView.reloadData()
}
}
// Setting up collection view
func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return self.brands.count
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
let cell:collectionViewCell = self.collectionView.dequeueReusableCellWithReuseIdentifier("Cell", forIndexPath: indexPath) as! collectionViewCell
// Get elements
let picToDisplay:UIImage? = pics[indexPath.row] // this is the error line
let dataToDisplay:String = brands[indexPath.row]
let imageView:UIImageView? = cell.viewWithTag(2) as? UIImageView
// Set labels
cell.brandImage.image = picToDisplay
cell.brandLabel.text = dataToDisplay
return cell
}
///////////////////////////////
struct brandCollection {
var brandText:[String] = [String]()
var brandImage:[UIImage?] = [UIImage]()
}
答案 0 :(得分:0)
您有brands.count
项,并且需要brand.count
张图片。但是您使用的是另一个数组pics
,如果它的元素少于brands
,则会失败。看看你的代码,有几种可能性可能发生。
这是糟糕的设计。您应该有一个数据数组,它封装了您需要的所有信息。每个图像都应连接到其对象(品牌),而不是保存在其他阵列中。