Question

这是我的代码，请帮助，我正在按照教程，但我无法弄清楚什么是错的。请帮忙。

我试图制作如果选择了图像，然后执行segue到另一个视图控制器并显示之前选择的图像

 override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath)
{
    self.performSegueWithIdentifier("showImage", sender: self)
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?)
{
    if segue.identifier == "showImage"
    {
        let indexPaths = self.collectionView!.indexPathsForSelectedItems()!
        let indexPath = indexPaths[0] as NSIndexPath
        let vc = segue.destinationViewController as! SecondViewController
        vc.image = self.url[indexPath.row] //Error Cannot Assign a value of type 'String' to type 'UIImage'
    }
}

我会感谢你的帮助。

Answer 1

vc.image = self.url[indexPath.row]，您将indexPath.row作为字符串，您必须在self.url["here"]内使用UIImage(named:"imagename")内的字符串中的图像获取所有self.url[UIImage(named:indexPath.row) } 并且视图控制器vc应该具有UIImage类型的图像变量。

Answer 2

self.url [indexPath.row] 给出一个字符串值，您无法直接将字符串分配给图像，这就是为什么它会抛出错误无法分配类型的值＆＃39;字符串＆＃39;输入＆＃39; UIImage＆＃39;

因此，您必须将其转换为数据，如下所示。例如

let ImageView = UIImageView()
let data = NSData(contentsOfURL: NSURL(string: "http://www.macmillandictionaryblog.com/wp-content/uploads/2011/07/Small-Talk-image.jpg")!)
ImageView.image = UIImage(data: data!)

在您的情况下，以下代码可能会有所帮助，我认为 Self.url 是一个包含图片网址的数组

if segue.identifier == "showImage"
{
    let indexPaths = self.collectionView!.indexPathsForSelectedItems()!
    let indexPath = indexPaths[0] as NSIndexPath
    let vc = segue.destinationViewController as! SecondViewController
    let URLStr = self.url[indexPath.row] as! String
    let data = NSData(contentsOfURL: NSURL(string: URLStr)!)
    vc.image.image = UIImage(data: data!) //Now it will work if vc.image is an UIImageView
}

Answer 3

使用此代码在Swift4中可以正常工作

    let subCategory = tableData[indexPath.row]
    let urlString = "https://www.youtube.com/"
    print(urlString)
    let url = URL(string: urlString!)
    let data = try? Data(contentsOf: url!)
    if let imageData = data {
        let image = UIImage(data: imageData)
        cell?.userPicImage.image = image
    }else {
        cell?.userPicImage.image = UIImage(named: "SomeEmptyImage")
    }

Answer 4

这很简单

let url = NSURL(string:"<image url>")
    let imagedata = NSData.init(contentsOf: url! as URL)

if imagedata != nil {
    cell.imageView.image = UIImage(data:imagedata! as Data)
}

无法指定类型'String'的值来键入'UIImage'

4 个答案: