如何从照片库加载动画GIF

Question

在iOS Swift中,我很难将动画GIF从设备照片库加载到UIImageView或从中创建.gif文件.如果它是服务器上的文件或者它在应用程序中是正确的,我可以显示动画GIF.但是,当我从照片库加载它时,我丢失了动画.我发现了一些Objective-C解决方案并尝试将它们转换为Swift,但没有任何运气.

这是我到目前为止:

@IBAction func buttonTapped(sender: UIButton) {
    selectPhoto()
}

func selectPhoto() {
    let photoLibraryController = UIImagePickerController()
    photoLibraryController.delegate = self
    photoLibraryController.sourceType = UIImagePickerControllerSourceType.PhotoLibrary

    let mediaTypes:[String] = [kUTTypeImage as String]
    photoLibraryController.mediaTypes = mediaTypes
    photoLibraryController.allowsEditing = false

    self.presentViewController(photoLibraryController, animated: true, completion: nil)
}

// UIImagePickerControllerDelegate
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
    let origImage = info[UIImagePickerControllerOriginalImage] as! UIImage

    self.imageView.image = origImage

    picker.dismissViewControllerAnimated(true, completion: nil)

}

最理想的情况是,我想将照片库图像保存到服务器上的gif文件中.从那里我可以毫不费力地显示它.但是,我需要一些帮助将照片库中的数据转换为某种类型的属性,而不会丢失动画.我需要使用像ALAssetsLibrary这样的东西吗？

谢谢.

Answer 1

是的,使用ALAssetsLibrary→现在称为PHAsset.

你应该得到gif的NSData,而不是UIImage(因为UIImage只会得到第一帧.)

所以基本上你会做这样的事情:

一个你获得资产

let requestOptions = PHImageRequestOptions()
requestOptions.isSynchronous = true // adjust the parameters as you wish    

PHImageManager.default().requestImageData(for: asset, options: requestOptions, resultHandler: { (imageData, UTI, _, _) in
    if let uti = UTI,let data = imageData ,
        // you can also use UTI to make sure it's a gif
       UTTypeConformsTo(uti as CFString, kUTTypeGIF) {
        // save data here
    }
})      

资源:PHAsset