swift - PHAsset 到 UIImage

Question

我正在尝试从 PHAsset 创建 UIImage(如缩略图或其他内容)，以便我可以将其传递到需要 UIImage 的内容中。我尝试过调整我在SO上找到的解决方案(因为它们都直接将其传递到表格 View 或其他东西中)，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 行现在没有执行任何操作。我如何让它以 UIImage 的形式提供 Assets 。

谢谢。

Answer 1

这完成了我需要它做的事情，以防有人也需要这个。

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
}

编辑:Swift 3 更新

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
}