The document outlines the features of watchOS 2, including its architecture designed to reduce dependency on iPhone, the introduction of new interface elements, and communication methods for apps. It covers improvements in app interactions through the use of a new API for messaging and complications, as well as the Taptic Engine for haptic feedback. Additional topics include accessibility features, open system URLs, and guidelines for building watch apps.

1. Introducing Features
of WatchOS 2
Joe
2015/7/17

2. Outline
• Architecture of WatchOS 2
• A bunch of new interface elements.
• Complications. (ClockKit)
• Taptic Engine.
• Accessibility
• Open System URL
• Hints of building Watch app

3. Architecture of
WatchOS 2

4. Architecture of WatchOS 2
(In order to remove the dependency from
iPhone)

5. Extensions built specifically for watchOS 2 have
access to the following system frameworks

6. WatchOS 2 provides ways for communicating with
iOS app or network
• Communicate with network：NSURLSession
• Communicate with iOS app：Watch Connectivity

7. Watch App communicates with iOS App
and vice versa
(Watch Connectivity)
• Precondition：WCSession.isSupported()
• Communication categories
• Background transfers
• Interactive messaging

8. Background transfers
• Best when information isn’t needed immediately
• Operating system determines the most suitable
time to send the data
• Content is queued up for transfer

9. Three ways of communicating
for background transfers
• Application Context：Information waiting in a
transfer queue will get overridden by the latest
data.
• User Info Transfer：Information waiting in a
transfer queue will deliver one by one in FIFO
order.(Like openParentApplication)
• File Transfer：Transfer files

10. Interactive messaging
• Precondition：iOS and watch App must be in
reachable state.(They must be connected via
Bluetooth) and watch app must be running in
the foreground.

11. Demo

12. API for background transfers
• Application Context：
• Sender：updateApplicationContext(_:)
• Receiver：session(_:didReceiveApplicationContext:)
• User Info Transfer：
• Sender：transferUserInfo(_:)
• Receiver：session(_:didReceiveUserInfo:)
• File Transfer：
• Sender：transferFile(_:metadata:)
• Receiver：session(_:didReceiveFile:)
Sender has an instance of WCSession
Receiver is instance which implements
WCSessionDelegate

13. API for interactive
messaging
• Sender
• sendMessage(_:replyHandler: errorHandler:)
• sendMessageData(_:replyHandler: errorHandler:)
• Receiver
• session(_:didReceiveMessage:replyHandler:)
• session(_:didReceiveMessageData:replyHandler:)

14. A bunch of new
interface elements

15. A bunch of new interface
elements
• WKInterfacePicker (Digital crown)
• Alerts and Action Sheets
• WKInterfaceMovie
• WKInterfaceController
• Playing Short Audio and Video Clips(Behavior like WKInterfaceMovie)
• Recording Short Audio Clips
• Animation
• WKAudioFilePlayer
• Playing Extended Audio Content (It needed to connect a blue tooth headset
now)

16. Demo

17. WKInterfacePicker
• A WKInterfacePicker object displays a
sequence of items that the user can navigate
through using the Digital Crown.
• Three types：list、stack、sequence
• Advance：Coordinated images

18. Alerts and Action Sheets
• Alerts and action sheets offer a standard interface for
displaying messages to the user.When tapped, the buttons
call blocks of code that you provide.
• WKInterfaceController：
presentAlertControllerWithTitle:message:preferredStyle:acti
ons:
• WKAlertControllerStyle：Alert, ActionSheet,
SideBySideButtonAlert
• WKAlertAction：Default, Cancel, Destructive

19. WKInterfaceMovie
• A WKInterfaceMovie object lets you embed short
audio or video clips directly into your interface.
• setMovieURL(URL: NSURL)
• setVideoGravity(videoGravity: WKVideoGravity)
• setLoops(loops: Bool)
• setPosterImage(posterImage: WKImage?)

20. Playing Short Audio and
Video Clips
• presentMediaPlayerControllerWithURL(URL:
NSURL, options: [NSObject : AnyObject]?,
completion: (Bool, NSTimeInterval, NSError?) ->
Void)
• dismissMediaPlayerController

21. Recording Short Audio Clips
• presentAudioRecordingControllerWithOutputUR
L(URL: NSURL, preset:
WKAudioRecordingPreset, maximumDuration:
NSTimeInterval, actionTitle: String?, completion:
(Bool, NSError?) -> Void)
• dismissAudioRecordingController

22. Animation
• WKInterfaceController
• animateWithDuration:

23. Playing Extended Audio Content
(WKAudioFilePlayer)
• Precondition: It needed to connect a Bluetooth
Headset with watch.
• WKAudioFilePlayer play WKAudioFilePlayerItem
which contains WKAudioFileAsset(URL, title,
albumTitle, artist, duration)

24. Complications.
(ClockKit)

25. Four ways to show
information from your app
• Watch app
• Glance
• Notification
• Complication

26. Complication

27. Timeline
( The data that changes by time)

28. CLKComplicationDataSource
• getSupportedTimeTravelDirectionsForComplication
• getTimelineStartDateForComplication
• getTimelineEndDateForComplication
• getPrivacyBehaviorForComplication
• getCurrentTimelineEntryForComplication
• getTimelineEntriesForComplication
• getNextRequestedUpdateDateWithHandler
• getPlaceholderTemplateForComplication

29. CLKComplicationTimelineEntry
Different timing (date) corresponding to layout (template)

30. A bunch of templates

31. Template
(Layout of complication)
e.g. CLKComplicationTemplateModularLargeStandardBody
headerText
body2Text
body1Text
Text is not type of string.

32. CLKTextProvider
(It is an abstract class)
• e.g. shows “Thursday, October 22” on
complication by CLKDateTextProvider (truncate
automatically)
• Thur, October 22
• Thur, Oct 22
• Oct 22
• 22

33. Demo

34. Taptic Engine

35. Provide physical feedback
via the Taptic Engine
• WKInterfaceDevice.currentDevice().playHaptic(h
apticType)
• hapticType：Notification, DirectionUp,
DirectionDown, Success, Failure, Retry, Start,
Stop, Click

36. Accessibility

37. Apple Watch Accessibility
• setAccessibilityLabel(accessibilityLabel: String?)
• setAccessibilityHint(accessibilityHint: String?)
• setAccessibilityValue(accessibilityValue: String?)
• setIsAccessibilityElement(isAccessibilityElement: Bool)
• setAccessibilityTraits(accessibilityTraits:
UIAccessibilityTraits)
• setAccessibilityImageRegions(accessibilityImageRegions
: [WKAccessibilityImageRegion])

38. Open System URL

39. Open System URL
• url:
• tel:
• sms:
• mailto:
• facetime:
• http://maps.apple.com/?daddr=San+Francisco,+CA&saddr=cupertino
• http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewAlbum?
i=156093464&id=156093462&s=143441
• http://www.youtube.com/v/VIDEO_IDENTIFIER
WKExtension.sharedExtension()
.openSystemURL(url)

40. Hints of building
Watch app

41. Hints of building Watch app
• UI is stored in Watch app
• One controller per screen of content
• Layout of WatchKit is flow-based layout
• Code updates UI from the extension
• Manages UI elements through outlets
• Uses target-action design pattern
• Profile with Instruments

42. Reference
• https://developer.apple.com/watch/human-
interface-guidelines/
• http://www.kristinathai.com/watchos-2-how-to-
communicate-between-devices-using-watch-
connectivity/
• watchOS 2 Transition Guide
• https://github.com/joehsieh/watchOS-2-Sampler

43. Q & A