The document provides an overview of 3D Touch, introduced with the iPhone 6s and iPhone 6s Plus, detailing its features like home screen quick actions and peek and pop functionality. It includes practical guidance on implementing 3D Touch within apps, showcasing dynamic shortcut creation, handling quick actions, and best practices for user interactions. Additionally, it covers low-level force API access for tracking pressure sensitivity in user interactions.

1. Adopting 3D Touch
Juan Catalan
jcatalan007@gmail.com

2. Agenda
• What is 3D Touch
• Home Screen Quick actions
• Peek and Pop
• Pressure Sensitivity

3. What is 3D Touch?
• With the introduction of the iPhone 6s and the iPhone
6s Plus, Apple added 3D Touch, a new dimension to
the multi-touch user interface.
• This new technology senses how deeply users press
the display and provides a new way to interact with
the iPhone.
• In iOS 9, Apple introduced several 3D Touch APIs. In
this session I will explain in a practical way what is 3D
Touch and how you can benefit from it in your app.

4. 3D Touch at a glance
https://developer.apple.com/ios/3d-touch/

5. Demo: sample app

6. Home Screen Quick actions

7. Home Screen Quick actions
Static
Defined in app’s info.plist
Available when the app is installed
Dynamic
Created by the app at runtime
Available after the first launch of the app
Shown after any static quick actions (if there is enough space)
Can include a system icon, custom icon, or Address Book contact

8. Home Screen Quick actions
Static
Defined in app’s info.plist
Available when the app is installed

9. Home Screen Quick actions
Dynamic: creating and registering
func createDynamicShortcuts() {
let application = UIApplication.shared
let bundleIdentifier = Bundle.main.bundleIdentifier!
var items = [UIMutableApplicationShortcutItem]()
if let (favoriteAsset, indexOfFavorite) = AssetStorage.sharedStorage.mostRecentFavoriteAsset() {
let favoriteShortcut = UIMutableApplicationShortcutItem(
type: "(bundleIdentifier).Favorite",
localizedTitle: favoriteAsset.name,
localizedSubtitle: favoriteAsset.detail,
icon: UIApplicationShortcutIcon(type: .love),
userInfo: ["version": Bundle.main.fullVersionNumber!, "index":indexOfFavorite]
)
items.append(favoriteShortcut)
}
let (recentAsset, indexOfRecent) = AssetStorage.sharedStorage.mostRecentNonFavoriteAsset()
let recentShortcut = UIMutableApplicationShortcutItem(
type: "(bundleIdentifier).Recent",
localizedTitle: recentAsset.name,
localizedSubtitle: recentAsset.detail,
icon: UIApplicationShortcutIcon(type: .task),
userInfo: ["version": Bundle.main.fullVersionNumber!, "index":indexOfRecent]
)
items.append(recentShortcut)
application.shortcutItems = items
}

10. Home Screen Quick actions
Dynamic: creating and registering
func createDynamicShortcuts() {
let application = UIApplication.shared
let bundleIdentifier = Bundle.main.bundleIdentifier!
var items = [UIMutableApplicationShortcutItem]()
if let (favoriteAsset, indexOfFavorite) = AssetStorage.sharedStorage.mostRecentFavoriteAsset() {
let favoriteShortcut = UIMutableApplicationShortcutItem(
type: "(bundleIdentifier).Favorite",
localizedTitle: favoriteAsset.name,
localizedSubtitle: favoriteAsset.detail,
icon: UIApplicationShortcutIcon(type: .love),
userInfo: ["version": Bundle.main.fullVersionNumber!, "index":indexOfFavorite]
)
items.append(favoriteShortcut)
}
let (recentAsset, indexOfRecent) = AssetStorage.sharedStorage.mostRecentNonFavoriteAsset()
let recentShortcut = UIMutableApplicationShortcutItem(
type: "(bundleIdentifier).Recent",
localizedTitle: recentAsset.name,
localizedSubtitle: recentAsset.detail,
icon: UIApplicationShortcutIcon(type: .task),
userInfo: ["version": Bundle.main.fullVersionNumber!, "index":indexOfRecent]
)
items.append(recentShortcut)
application.shortcutItems = items
}

11. Handling Quick actions
On app activation
func application(_ application: UIApplication, performActionFor shortcutItem: UIApplicationShortcutItem,
completionHandler: @escaping (Bool) -> Void) {
let handled = handleSortCutItem(shortcutItem)
completionHandler(handled)
}
func handleSortCutItem(_ shortcutItem: UIApplicationShortcutItem) -> Bool {
var vcs = (window!.rootViewController as! UINavigationController).viewControllers
if vcs.count > 1 {
vcs.last!.performSegue(withIdentifier: "UnwindToMainSegue", sender: nil)
vcs = (window!.rootViewController as! UINavigationController).viewControllers
}
let main = vcs.first as! MainTableViewController
switch shortcutItem.type {
case "net.bitcrafters.3DTouchDemo.AddAsset":
main.performSegue(withIdentifier: "NewAssetSegue", sender: nil)
case "net.bitcrafters.3DTouchDemo.Favorite":
main.segueForShortcutToDetail(shortcutItem.userInfo?["index"] as! Int)
case "net.bitcrafters.3DTouchDemo.Recent":
main.segueForShortcutToDetail(shortcutItem.userInfo?["index"] as! Int)
default:
return false
}
return true
}

12. Handling Quick actions
On app launch
var launchedShortcutItem: UIApplicationShortcutItem?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions:
[UIApplicationLaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
var performAdditionalHandling = true
if let shortcutItem = launchOptions?[UIApplicationLaunchOptionsKey.shortcutItem] as?
UIApplicationShortcutItem {
launchedShortcutItem = shortcutItem
performAdditionalHandling = false
}
createDynamicShortcuts()
return performAdditionalHandling
}
func applicationDidEnterBackground(_ application: UIApplication) {
createDynamicShortcuts()
}
func applicationDidBecomeActive(_ application: UIApplication) {
guard let shortcut = launchedShortcutItem else { return }
let _ = handleSortCutItem(shortcut)
launchedShortcutItem = nil
}

13. Demo: quick actions

14. Home Screen Quick actions
Best practices / design considerations
Every app should provide quick actions
Focus on providing quick access to high-value tasks
Make quick actions predictable
Be prepared to handle dynamic quick actions from a previous
version of your app
Don’t add functionality that is only accessible using quick actions
Implement navigation to the desired feature triggered by the shortcut
Update the dynamic shortcuts to have them ready

15. Peek and Pop
Peek Pop
Preview Commit

16. Peek and Pop
Registered View Controller Previewed View Controller
Source

17. Peek and Pop
Conforming to UIViewControllerPreviewDelegate
override func viewDidLoad() {
super.viewDidLoad()
registerForPreviewing(with: self, sourceView: tableView)
}
…
extension MainTableViewController: UIViewControllerPreviewingDelegate {
func previewingContext(_ previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) ->
UIViewController? {
guard
let indexPath = tableView.indexPathForRow(at: location),
let detailViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier:
"DetailViewController") as? DetailViewController
else {
return nil
}
detailViewController.index = indexPath.row
let cellRect = tableView.rectForRow(at: indexPath)
let sourceRect = previewingContext.sourceView.convert(cellRect, from: tableView)
previewingContext.sourceRect = sourceRect
return detailViewController
}
func previewingContext(_ previewingContext: UIViewControllerPreviewing, commit viewControllerToCommit: UIViewController) {
show(viewControllerToCommit, sender: self)
}
}

18. Peek and Pop
Registering for previewing
override func viewDidLoad() {
super.viewDidLoad()
registerForPreviewing(with: self, sourceView: tableView)
}
…
extension MainTableViewController: UIViewControllerPreviewingDelegate {
func previewingContext(_ previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) ->
UIViewController? {
guard
let indexPath = tableView.indexPathForRow(at: location),
let detailViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier:
"DetailViewController") as? DetailViewController
else {
return nil
}
detailViewController.index = indexPath.row
let cellRect = tableView.rectForRow(at: indexPath)
let sourceRect = previewingContext.sourceView.convert(cellRect, from: tableView)
previewingContext.sourceRect = sourceRect
return detailViewController
}
func previewingContext(_ previewingContext: UIViewControllerPreviewing, commit viewControllerToCommit: UIViewController) {
show(viewControllerToCommit, sender: self)
}
}

19. Peek and Pop
Providing a preview view controller
override func viewDidLoad() {
super.viewDidLoad()
registerForPreviewing(with: self, sourceView: tableView)
}
…
extension MainTableViewController: UIViewControllerPreviewingDelegate {
func previewingContext(_ previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) ->
UIViewController? {
guard
let indexPath = tableView.indexPathForRow(at: location),
let detailViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier:
"DetailViewController") as? DetailViewController
else {
return nil
}
detailViewController.index = indexPath.row
let cellRect = tableView.rectForRow(at: indexPath)
let sourceRect = previewingContext.sourceView.convert(cellRect, from: tableView)
previewingContext.sourceRect = sourceRect
return detailViewController
}
func previewingContext(_ previewingContext: UIViewControllerPreviewing, commit viewControllerToCommit: UIViewController) {
show(viewControllerToCommit, sender: self)
}
}

20. Peek and Pop
Committing a preview view controller
override func viewDidLoad() {
super.viewDidLoad()
registerForPreviewing(with: self, sourceView: tableView)
}
…
extension MainTableViewController: UIViewControllerPreviewingDelegate {
func previewingContext(_ previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) ->
UIViewController? {
guard
let indexPath = tableView.indexPathForRow(at: location),
let detailViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier:
"DetailViewController") as? DetailViewController
else {
return nil
}
detailViewController.index = indexPath.row
let cellRect = tableView.rectForRow(at: indexPath)
let sourceRect = previewingContext.sourceView.convert(cellRect, from: tableView)
previewingContext.sourceRect = sourceRect
return detailViewController
}
func previewingContext(_ previewingContext: UIViewControllerPreviewing, commit viewControllerToCommit: UIViewController) {
show(viewControllerToCommit, sender: self)
}
}

21. Demo: peek and pop

22. Peek and Pop
Using the Storyboard

23. Demo: storyboard peek & pop

24. Peek and Pop (Preview quick actions)
Source

25. Peek and Pop
Adding preview quick actions
// MARK: Preview actions, in DetailViewController
override var previewActionItems : [UIPreviewActionItem] {
var favoriteTitle: String
if asset.favorite {
favoriteTitle = "💔 (self.asset.name)"
} else {
favoriteTitle = "❤ (self.asset.name)"
}
let favoriteAction = UIPreviewAction(title: favoriteTitle, style: .default) { (action,
viewController) in
self.asset.favorite = !self.asset.favorite
AssetStorage.sharedStorage.update(self.asset, atIndex: self.index!)
NotificationCenter.default.post(name: DetailViewController.updateUINotification, object:
nil)
}
let deleteAction = UIPreviewAction(title: "Delete (self.asset.name)", style: .destructive)
{ (action, viewController) in
AssetStorage.sharedStorage.delete(assetAtIndex: self.index!)
NotificationCenter.default.post(name: DetailViewController.updateUINotification, object: nil)
}
return [favoriteAction, deleteAction]
}

26. Demo: peek and pop

27. Peek and Pop
Best practices
Content that can be tapped should support Peek and Pop
Return a preview view controller consistently
Don’t take too long in the previewing delegate
Set the previewing context sourceRect

28. Low-Level Force API
Normalized access to force data
Properties on UITouch: force and maximumPossibleForce
Available on devices that support 3D Touch or Apple Pencil

29. Low-Level Force API
Using UITouch
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
if #available(iOS 9.0, *) {
if traitCollection.forceTouchCapability == UIForceTouchCapability.available {
if touch.force >= touch.maximumPossibleForce {
forceLabel.text = "385+ grams"
} else {
let force = touch.force/touch.maximumPossibleForce
let grams = force * 385
let roundGrams = Int(grams)
forceLabel.text = "(roundGrams) grams"
}
}
}
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
forceLabel.text = "0 gram"
}
http://www.appcoda.com/3d-touch-tutorial/

30. Demo: Low-Level Force API

31. 3D Touch summary
https://developer.apple.com/ios/3d-touch/

32. Reference
https://developer.apple.com/ios/3d-touch/
https://developer.apple.com/library/content/
documentation/UserExperience/Conceptual/
Adopting3DTouchOniPhone/index.html
http://www.appcoda.com/3d-touch-tutorial/

33. Thanks!
• Source code
https://github.com/jcatalan007/3DTouch-talk
• Slides
https://www.slideshare.net/jcatalan007/
adopting-3d-touch-in-your-apps