我正在尝试从PHAsset创建一个UIImage(如缩略图或其他东西),以便我可以将它传递给需要UIImage的东西.我已经尝试调整我在SO上找到的解决方案(因为他们都直接将它传递到tableview或其他东西),但我没有成功(可能是因为我做得不对).
func getAssetThumbnail(asset: PHAsset) -> UIImage {
var retimage = UIImage()
println(retimage)
let manager = PHImageManager.defaultManager()
manager.requestImageForAsset(asset, targetSize: CGSize(width: 100.0, height: 100.0), contentMode: .AspectFit, options: nil, resultHandler: {(result, info)->Void in
retimage = result
})
println(retimage)
return retimage
}
printlns告诉我,manager.request行现在没有做任何事情.如何让它作为UIImage给我资产.
谢谢.
dch*_*eng 82
这就是我需要它做的事情,万一有人也需要它.
func getAssetThumbnail(asset: PHAsset) -> UIImage {
let manager = PHImageManager.defaultManager()
let option = PHImageRequestOptions()
var thumbnail = UIImage()
option.synchronous = true
manager.requestImageForAsset(asset, targetSize: CGSize(width: 100.0, height: 100.0), contentMode: .AspectFit, options: option, resultHandler: {(result, info)->Void in
thumbnail = result!
})
return thumbnail
}
func getAssetThumbnail(asset: PHAsset) -> UIImage {
let manager = PHImageManager.default()
let option = PHImageRequestOptions()
var thumbnail = UIImage()
option.isSynchronous = true
manager.requestImage(for: asset, targetSize: CGSize(width: 100, height: 100), contentMode: .aspectFit, options: option, resultHandler: {(result, info)->Void in
thumbnail = result!
})
return thumbnail
}
Pat*_*gar 24
试试这个对我有用,希望它对你有帮助,
func getUIImage(asset: PHAsset) -> UIImage? {
var img: UIImage?
let manager = PHImageManager.default()
let options = PHImageRequestOptions()
options.version = .original
options.isSynchronous = true
manager.requestImageData(for: asset, options: options) { data, _, _, _ in
if let data = data {
img = UIImage(data: data)
}
}
return img
}
小智 9
雨燕5
extension PHAsset {
func getAssetThumbnail() -> UIImage {
let manager = PHImageManager.default()
let option = PHImageRequestOptions()
var thumbnail = UIImage()
option.isSynchronous = true
manager.requestImage(for: self,
targetSize: CGSize(width: self.pixelWidth, height: self.pixelHeight),
contentMode: .aspectFit,
options: option,
resultHandler: {(result, info) -> Void in
thumbnail = result!
})
return thumbnail
}
}
简单的解决方案(Swift 4.2)
方法1:
extension PHAsset {
var image : UIImage {
var thumbnail = UIImage()
let imageManager = PHCachingImageManager()
imageManager.requestImage(for: self, targetSize: CGSize(width: 100, height: 100), contentMode: .aspectFit, options: nil, resultHandler: { image, _ in
thumbnail = image!
})
return thumbnail
}
}
let image = asset.image
如果您只需要UIImage,请使用此方法PHAsset.
要么
extension PHAsset {
func image(targetSize: CGSize, contentMode: PHImageContentMode, options: PHImageRequestOptions?) -> UIImage {
var thumbnail = UIImage()
let imageManager = PHCachingImageManager()
imageManager.requestImage(for: self, targetSize: targetSize, contentMode: contentMode, options: options, resultHandler: { image, _ in
thumbnail = image!
})
return thumbnail
}
}
let image = asset.image(targetSize: CGSize, contentMode: PHImageContentMode, options: PHImageRequestOptions?)
使用此方法为您所需UIImage.
要么
extension PHAsset {
func image(completionHandler: @escaping (UIImage) -> ()){
var thumbnail = UIImage()
let imageManager = PHCachingImageManager()
imageManager.requestImage(for: self, targetSize: CGSize(width: 100, height: 100), contentMode: .aspectFit, options: nil, resultHandler: { img, _ in
thumbnail = img!
})
completionHandler(thumbnail)
}
}
let image = asset.image(completionHandler: {(img) in
print("Finished")
})
完成后使用此方法进行通知.
方法2:
extension PHAsset {
var data : (UIImage, [AnyHashable : Any]) {
var img = UIImage(); var information = [AnyHashable : Any](); let imageManager = PHCachingImageManager()
imageManager.requestImage(for: self, targetSize: CGSize(width: 100, height: 100), contentMode: .aspectFit, options: nil, resultHandler: { image,info in
img = image!
information = info!
})
return (img,information)
}
}
let image_withData : (UIImage, [AnyHashable : Any]) = asset.data
如果您想要UIImage和结果信息,请使用此方法PHAsset
要么
extension PHAsset {
func data(targetSize: CGSize, contentMode: PHImageContentMode, options: PHImageRequestOptions?) -> (UIImage, [AnyHashable : Any]) {
var img = UIImage(); var information = [AnyHashable : Any](); let imageManager = PHCachingImageManager()
imageManager.requestImage(for: self, targetSize: targetSize, contentMode: contentMode, options: options, resultHandler: { image,info in
img = image!
information = info!
})
return (img,information)
}
}
let data = asset?.data(targetSize: CGSize, contentMode: PHImageContentMode, options: PHImageRequestOptions?)
将此方法用于所需的数据.
我建议使用Apple的PHCachingImageManager(继承自PHImageManager):
PHCachingImageManager对象为照片或视频资产提取或生成图像数据
此外,PHCachingImageManager支持更好的缓存机制.
获取同步缩略图的示例:
let options = PHImageRequestOptions()
options.deliveryMode = .HighQualityFormat
options.synchronous = true // Set it to false for async callback
let imageManager = PHCachingImageManager()
imageManager.requestImageForAsset(YourPHAssetVar,
targetSize: CGSizeMake(CGFloat(160), CGFloat(160)),
contentMode: .AspectFill,
options: options,
resultHandler: { (resultThumbnail : UIImage?, info : [NSObject : AnyObject]?) in
// Assign your thumbnail which is the *resultThumbnail*
}
此外,您可以使用PHCachingImageManager 缓存图像以获得更快的UI响应:
要使用缓存图像管理器:
创建PHCachingImageManager实例.(此步骤使用共享的PHImageManager实例替换.)
使用PHAsset类方法来获取您感兴趣的资产.
要为这些资源准备图像,请调用startCachingImagesForAssets:targetSize:contentMode:options:方法,其中包含目标大小,内容模式以及计划在以后为每个资产请求图像时使用的选项.
当您需要单个资产的图像时,请调用requestImageForAsset:targetSize:contentMode:options:resultHandler:method,并传递您在准备该资产时使用的相同参数.
如果您请求的图像是已经准备好的图像,则PHCachingImageManager对象会立即返回该图像.否则,照片会根据需要准备图像并将其缓存以供以后使用.
在我们的例子中:
var phAssetArray : [PHAsset] = []
for i in 0..<assets.count
{
phAssetArray.append(assets[i] as! PHAsset)
}
let options = PHImageRequestOptions()
options.deliveryMode = .Opportunistic
options.synchronous = false
self.imageManager.startCachingImagesForAssets(phAssetArray,
targetSize: CGSizeMake(CGFloat(160), CGFloat(160)),
contentMode: .AspectFill,
options: options)
对于Swift 3.0.1:
func getAssetThumbnail(asset: PHAsset, size: CGFloat) -> UIImage {
let retinaScale = UIScreen.main.scale
let retinaSquare = CGSize(width: size * retinaScale, height: size * retinaScale)//(size * retinaScale, size * retinaScale)
let cropSizeLength = min(asset.pixelWidth, asset.pixelHeight)
let square = CGRect(x:0, y: 0,width: CGFloat(cropSizeLength),height: CGFloat(cropSizeLength))
let cropRect = square.applying(CGAffineTransform(scaleX: 1.0/CGFloat(asset.pixelWidth), y: 1.0/CGFloat(asset.pixelHeight)))
let manager = PHImageManager.default()
let options = PHImageRequestOptions()
var thumbnail = UIImage()
options.isSynchronous = true
options.deliveryMode = .highQualityFormat
options.resizeMode = .exact
options.normalizedCropRect = cropRect
manager.requestImage(for: asset, targetSize: retinaSquare, contentMode: .aspectFit, options: options, resultHandler: {(result, info)->Void in
thumbnail = result!
})
return thumbnail
}
资源:https://gist.github.com/lvterry/f062cf9ae13bca76b0c6#file-getassetthumbnail-swift
斯威夫特4。
resizeMode，deliveryMode-这些可以根据用户要求进行设置。
isNetworkAccessAllowed -将其设置为“ true”以从云中获取图像
imageSize-所需的图像尺寸
func getImageFromAsset(asset:PHAsset,imageSize:CGSize, callback:@escaping (_ result:UIImage) -> Void) -> Void{
let requestOptions = PHImageRequestOptions()
requestOptions.resizeMode = PHImageRequestOptionsResizeMode.fast
requestOptions.deliveryMode = PHImageRequestOptionsDeliveryMode.highQualityFormat
requestOptions.isNetworkAccessAllowed = true
requestOptions.isSynchronous = true
PHImageManager.default().requestImage(for: asset, targetSize: imageSize, contentMode: PHImageContentMode.default, options: requestOptions, resultHandler: { (currentImage, info) in
callback(currentImage!)
})
}