WWDC Notes

Meet the new Photos picker

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Let people select photos and videos to use in your app without requiring full Photo Library access. Discover how the PHPicker API for iOS and Mac Catalyst ensures privacy while providing your app the features you need. PHPicker is the modern replacement for UIImagePickerController. In addition to its privacy-focused approach, the API also provides additional features for your app like search, multi-image selection, and the ability to zoom in or out on on the photo grid. We’ll show you how PHPicker can help most apps avoid asking for direct library access and how you can implement it to improve the overall experience for people interacting with your app.

PHPicker: a new system-provided picker screen that gives you access to photos and videos from the user’s photo library.

It’s recommended that you use this picker instead of building your own custom photo selection UI.

New version includes:

  • a new design and new easy to use API
  • an integrated search
  • easy multi-select
  • zoom gesture

PHPicker is private by default:

  • the picker screen runs out of process and talks to the app via XPC
  • your app has no direct access to the photos library
  • it doesn’t need to get photo library permission (don’t ask for it unless you really need it)
  • you only get selected photos and videos in response

PHPicker is not a name of a single class, but a set of classes that work together.

Elements of the API

PHPickerConfiguration – lets you specify limits and filters:

  • selectionLimit – number of items that can be selected (1 by default, 0 = unlimited)
  • filter – e.g. .images or .any(of: [.videos, .livePhotos])

PHPickerViewController – the main view controller handling the picker:

  • the picker doesn’t dismiss itself automatically, call picker.dismiss(animated:) when you get the response

PHPickerViewControllerDelegate – delegate for the picker:

PHPickerResult – an array of these objects is passed to the app in response

  • get itemProvider from the result
  • check itemProvider.canLoadObject(ofClass: UIImage.self)
  • get the image via itemProvider.loadObject(ofClass: UIImage.self) { … }

You can normally extract picked photos from PHPickerResult item providers without touching the PHPhotoLibrary at all, but if you do need to access the photo library anyway, then pass it to PHPickerConfiguration.init and get assetIdentifier references from the picker results.

If you use PHPicker with photo library access and you only got limited access to a subset of photos, then:

  • PHPicker will still let the user choose photos from their whole library
  • but the selection you have direct access to will not be extended by what they choose in the picker

The photo library APIs from UIImagePickerController are deprecated.

This note was originally published at https://mackuba.eu/notes/wwdc20/meet-the-new-photos-picker/

Full blog post here: https://mackuba.eu/2020/07/07/photo-library-changes-ios-14/

Missing anything? Corrections? Contributions are welcome 😃

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Written by

kuba_suder

Kuba Suder

Kuba Suder is an independent Mac/iOS/watchOS developer from Kraków, Poland. Currently busy working on his own apps and projects, learning more about Apple platforms and sharing the knowledge on his blog. Language of choice: Swift for apps, Ruby on the backend.

Twitter: @kuba_suder • Blog: mackuba.eu