我正在编写一个相册应用,可以从用户的照片库中访问照片,添加过滤器和删除照片。我使用Photo框架删除了PHAssetChangeRequest.deleteAssets(assetToDelete)
的资产。
此处的资产类别为PHAsset
。
// Delete the photo from library
@IBAction func deleteBtnPressed(_ sender: Any) {
let assetToDelete = self.asset
if let assetToDelete = assetToDelete
{
PHPhotoLibrary.shared().performChanges({
PHAssetChangeRequest.deleteAssets(assetToDelete)
})
}
}
但是错误发生在这里,“参数类型'PHAsset'不符合预期类型'NSFastEnumeration'”。
所以我按照Xcode推荐更改了assetToDelete的类型:
PHAssetChangeRequest.deleteAssets(assetToDelete as! NSFastEnumeration)
它仍然不起作用,错误显示:
无法将“PHAsset”类型的值转换为“NSFastEnumeration”
有谁知道如何处理这个问题?谢谢!
答案 0 :(得分:4)
线索的名称为'assets'复数 - API需要一个数组或符合NSFastEnumeration的任何其他集合类型,例如Set
PHAssetChangeRequest.deleteAssets([assetToDelete])
https://developer.apple.com/documentation/photos/phassetchangerequest/1624062-deleteassets
答案 1 :(得分:2)
更正确的方法是先从库中获取:
let assetIdentifiers = assetsToDeleteFromDevice.map({ $0.localIdentifier })
let assets = PHAsset.fetchAssets(withLocalIdentifiers: assetIdentifiers, options: nil)
PHPhotoLibrary.shared().performChanges({
PHAssetChangeRequest.deleteAssets(assets)
})