IOS Swift 图像加载到 UIImageView 时旋转

Question

在我的应用程序中，我有一个按钮可以打开图库，如下所示:

@IBAction func selectPhoto() {
    let photoPicker = UIImagePickerController()
    photoPicker.delegate = self
    photoPicker.sourceType = .PhotoLibrary
    self.presentViewController(photoPicker, animated: true, completion: nil)
}

我让用户选择一张照片并保存它:

func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
    photoImageView.image = info[UIImagePickerControllerOriginalImage] as? UIImage        
    let fileName:String = "logo.png"        
    let arrayPaths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as NSString        
    let pngFileName = arrayPaths.stringByAppendingPathComponent(fileName)                UIImagePNGRepresentation(photoImageView.image!)!.writeToFile(pngFileName, atomically:true)        
    imageSave.setObject(fileName, forKey: "pngFileName")        
    self.dismissViewControllerAnimated(false, completion: nil)
}

然后，从 View Controller 中，每次用户使用以下代码到达场景时都会显示保存的图片。

 override func viewDidLoad() {
    super.viewDidLoad()

    if imageSave.stringForKey("pngFileName") != nil
    {
        let path = NSSearchPathForDirectoriesInDomains(
            .DocumentDirectory, .UserDomainMask, true)[0] as NSString
        let fileName = NSUserDefaults.standardUserDefaults()
            .stringForKey("pngFileName")
        let imagePath = path.stringByAppendingPathComponent(fileName!)
        let image = UIImage(contentsOfFile: imagePath )            
        photoImageView.image = image

    }

问题:当图像加载回 UIImageView 时，图片的方向有时会向右旋转 90 度，有时会向左旋转 90 度，有时会显示为保存时的样子。

请让我知道我在这里做错了什么。任何帮助，将不胜感激。谢谢

Answer 1

我遇到了同样的问题，因为照片显示的矩形大小不同。您可以使用一个技巧，将原始图像保存为复制版本。这将丢弃旋转问题，这实际上是一个拟合问题。

let imageName = info[UIImagePickerControllerOriginalImage] as! UIImage
let thumb1 = UIImageJPEGRepresentation(imageName, 0.8)
btnImageView.image = UIImage(data: thumb1!)

这只是一个快速而肮脏的答案，但对我有用。 :-)