keeping your watch app up to date - apple developer · 2016-07-08 · austen green watchos...
TRANSCRIPT
© 2016 Apple Inc. All rights reserved. Redistribution or public display not permitted without written permission from Apple.
App Frameworks #WWDC16
Session 218
Keeping Your Watch App Up to Date
Eric Lanz watchOS EngineerAusten Green watchOS Engineer
Overview
Walkthrough
Scheduling
Best Practices
Case Study
User modelOverview
User modelOverview
Waiting for Coffee
User modelOverview
Waiting for Coffee
Check Weather
User modelOverview
Waiting for Coffee
Check Weather
Find a Lunch Spot
User modelOverview
Waiting for Coffee
Check Weather
Find a Lunch Spot
Receive Notification
User modelOverview
Waiting for Coffee Check Traffic
Check Weather
Find a Lunch Spot
Receive Notification
User modelOverview
Waiting for Coffee Find a Lunch Spot Check Traffic
Check Weather Receive Notification Quick Reply
User modelOverview
Waiting for Coffee Check Traffic
Check Weather Quick Reply
Find a Lunch Spot
Receive Notification
SchedulingOverview
Check Weather
Background Foreground
SchedulingOverview
Update UI
Background Foreground
Check Weather
SchedulingOverview
Update UIFetch Data
Background Foreground
Check Weather
SchedulingOverview
Background Foreground
Check Weather
Update UIFetch DataWake Up
Tasks
watchOS
Suspended
Task
Task Task
Task
Task
Task Task Task
Applications
Tasks
Active
ApplicationswatchOS
Task
Task Task
Task
Task Task Task
Task
Tasks
Active
ApplicationswatchOS
Task
Task Task
Task
Task Task Task
Task
Tasks
Active
watchOS Applications
Task
Task Task
Task
Task Task Task
Taskfunc handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>)
Tasks
Suspended
watchOS Applications
Task
Task Task
Task
Task Task Task
Task
Tasks
Suspended
watchOS Applications
Task
Task Task
Task
Task Task Task
Task
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Schedule using Watch Connectivity
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
Schedule using URLSession
Schedule using Watch Connectivity
WKExtension: scheduleBackgroundRefresh
WKExtension: scheduleSnapshotRefresh
Wake upTasks
Check Weather
Background Foreground
Application Task
Update UIFetch DataWake Up
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
Schedule using Watch Connectivity
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
Schedule using Watch Connectivity
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Fetch dataTasks
Check Weather
Background Foreground
URLSession Task
Update UIFetch DataWake Up
Snapshots
Snapshots
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Schedule using Watch Connectivity
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Schedule using Watch Connectivity
SnapshotTasks
Check Weather
Background Foreground
Snapshot Task
Update UIFetch DataWake Up
Meet expectationsSnapshots
Optional default stateSnapshots
More informationSnapshots
Designing Great Apple Watch Experiences Presidio Wednesday 1:40PM
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Schedule using Watch Connectivity
SummaryTasks
WKWatchConnectivityRefreshBackgroundTask
WKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
WKSnapshotRefreshBackgroundTask
WKExtension: scheduleBackgroundRefresh
Schedule using URLSession
WKExtension: scheduleSnapshotRefresh
Schedule using Watch Connectivity
Watch connectivityTasks
Watch connectivityTasks
User Info
File
Context
Complication
Watch connectivityTasks
Is Session Active
NEW
Watch connectivityTasks
hasContentPendingIs Session Active
hasContentPending
Watch connectivityTasks
Is Session Active Complete Task
Schedule Background Runtime
Schedule Background Runtime
Receive Tasks
Schedule Background Runtime
Receive Tasks Do Work
Schedule Background Runtime
Receive Tasks Do Work
Schedule More Runtime
Schedule Background Runtime
Receive Tasks Do Work
Schedule More Runtime
Tell System When Done
Be a Good Citizen
Be a Good Citizen
User Launches App
3:00 PM
Be a Good Citizen
4:00 PM
Wake UpUser Launches App
3:00 PM
Be a Good Citizen
4:00 PM
Wake UpUser Launches App
3:50 PM
Be a Good Citizen
4:50 PM
Wake UpUser Launches App
3:50 PM
Walkthrough
Football scoresWalkthrough
7:00 PM 9:00 PM
Football scoresWalkthrough
7:00 PM 9:00 PM
Update Score Update Score Update Score
7:30 PM 8:00 PM 8:30 PM
Football scoresWalkthrough
7:00 PM 9:00 PM
7:30 PM 8:00 PM 8:30 PM
Update Score Update Score Update Score
Football scoresWalkthrough
7:00 PM 9:00 PM
7:30 PM 8:00 PM 8:30 PM
Update Score Update Score Update Score
Football scoresWalkthrough
7:00 PM 9:00 PM
7:30 PM 8:00 PM 8:30 PM
Update Score Update Score Update Score
// Scheduling Background Runtime
func myScheduleNextRefreshTask() {
let fireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes from now
let userInfo = ["lastActiveDate" : Date(), // optional last active time
"reason" : “scoreUpdate”] // optional reason
WKExtension.shared().scheduleBackgroundRefresh(withPreferredDate: fireDate
, userInfo: userInfo) { (error) in
if error == nil {
// successfully scheduled
}
}
}
// Scheduling Background Runtime
func myScheduleNextRefreshTask() {
let fireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes from now
let userInfo = ["lastActiveDate" : Date(), // optional last active time
"reason" : “scoreUpdate”] // optional reason
WKExtension.shared().scheduleBackgroundRefresh(withPreferredDate: fireDate
, userInfo: userInfo) { (error) in
if error == nil {
// successfully scheduled
}
}
}
// Scheduling Background Runtime
func myScheduleNextRefreshTask() {
let fireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes from now
let userInfo = ["lastActiveDate" : Date(), // optional last active time
"reason" : “scoreUpdate”] // optional reason
WKExtension.shared().scheduleBackgroundRefresh(withPreferredDate: fireDate
, userInfo: userInfo) { (error) in
if error == nil {
// successfully scheduled
}
}
}
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:30:00
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:30:02
Fetch Data
// Fetching Data in the Background
func myScheduleURLSession() {
let backgroundConfigObject = URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: "com.example.urlsession")
let backgroundSession = URLSession(configuration: backgroundConfigObject)
let downloadTask = backgroundSession.downloadTask(
with: URL(string: "https://example.com/currentScores.json")!)
downloadTask.resume()
}
// Fetching Data in the Background
func myScheduleURLSession() {
let backgroundConfigObject = URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: "com.example.urlsession")
let backgroundSession = URLSession(configuration: backgroundConfigObject)
let downloadTask = backgroundSession.downloadTask(
with: URL(string: "https://example.com/currentScores.json")!)
downloadTask.resume()
}
// Fetching Data in the Background
func myScheduleURLSession() {
let backgroundConfigObject = URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: "com.example.urlsession")
let backgroundSession = URLSession(configuration: backgroundConfigObject)
let downloadTask = backgroundSession.downloadTask(
with: URL(string: "https://example.com/currentScores.json")!)
downloadTask.resume()
}
// Fetching Data in the Background
func myScheduleURLSession() {
let backgroundConfigObject = URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: "com.example.urlsession")
let backgroundSession = URLSession(configuration: backgroundConfigObject)
let downloadTask = backgroundSession.downloadTask(
with: URL(string: "https://example.com/currentScores.json")!)
downloadTask.resume()
}
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:30:05
Fetch Data
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up Fetch Data Update Model
7:33:00
// Handling Background Tasks// WKExtensionDelegate
func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>) {
for task in backgroundTasks {
if let urlTask = task as? WKURLSessionRefreshBackgroundTask
let backgroundConfigObject
URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: urlTask.sessionIdentifier)
let backgroundSession = URLSession(configuration: backgroundConfigObject,
delegate: self,
delegateQueue: nil)
// receive data via URLSessionDownloadDelegate
pendingBackgroundTasks.append(task)
} else {
task.setTaskCompleted() // make sure to complete all tasks
}
}
}
// Handling Background Tasks// WKExtensionDelegate
func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>) {
for task in backgroundTasks {
if let urlTask = task as? WKURLSessionRefreshBackgroundTask
let backgroundConfigObject
URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: urlTask.sessionIdentifier)
let backgroundSession = URLSession(configuration: backgroundConfigObject,
delegate: self,
delegateQueue: nil)
// receive data via URLSessionDownloadDelegate
pendingBackgroundTasks.append(task)
} else {
task.setTaskCompleted() // make sure to complete all tasks
}
}
}
// Handling Background Tasks// WKExtensionDelegate
func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>) {
for task in backgroundTasks {
if let urlTask = task as? WKURLSessionRefreshBackgroundTask
let backgroundConfigObject
URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: urlTask.sessionIdentifier)
let backgroundSession = URLSession(configuration: backgroundConfigObject,
delegate: self,
delegateQueue: nil)
// receive data via URLSessionDownloadDelegate
pendingBackgroundTasks.append(task)
} else {
task.setTaskCompleted() // make sure to complete all tasks
}
}
}
// Handling Background Tasks// WKExtensionDelegate
func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>) {
for task in backgroundTasks {
if let urlTask = task as? WKURLSessionRefreshBackgroundTask
let backgroundConfigObject
URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: urlTask.sessionIdentifier)
let backgroundSession = URLSession(configuration: backgroundConfigObject,
delegate: self,
delegateQueue: nil)
// receive data via URLSessionDownloadDelegate
pendingBackgroundTasks.append(task)
} else {
task.setTaskCompleted() // make sure to complete all tasks
}
}
}
// Handling Background Tasks// WKExtensionDelegate
func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>) {
for task in backgroundTasks {
if let urlTask = task as? WKURLSessionRefreshBackgroundTask
let backgroundConfigObject
URLSessionConfiguration.backgroundSessionConfiguration(
withIdentifier: urlTask.sessionIdentifier)
let backgroundSession = URLSession(configuration: backgroundConfigObject,
delegate: self,
delegateQueue: nil)
// receive data via URLSessionDownloadDelegate
pendingBackgroundTasks.append(task)
} else {
task.setTaskCompleted() // make sure to complete all tasks
}
}
}
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:33:02
Update UIFetch Data Update Model
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:30:05
Update UIFetch Data Update Model
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:34:00
Update UIFetch Data Update Model
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up
7:34:05
Update UIFetch Data Update Model
// Completing Snapshot Task
func myCompleteSnapshotTask(snapTask : WKSnapshotRefreshBackgroundTask) {
let expireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes
let userInfo = ["lastActiveDate" : Date()]
let restoredDefaultState = false
snapTask.setTaskCompleted(restoredDefaultState: restoredDefaultState,
estimatedSnapshotExpiration: expireDate,
userInfo: userInfo)
}
// Completing Snapshot Task
func myCompleteSnapshotTask(snapTask : WKSnapshotRefreshBackgroundTask) {
let expireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes
let userInfo = ["lastActiveDate" : Date()]
let restoredDefaultState = false
snapTask.setTaskCompleted(restoredDefaultState: restoredDefaultState,
estimatedSnapshotExpiration: expireDate,
userInfo: userInfo)
}
// Completing Snapshot Task
func myCompleteSnapshotTask(snapTask : WKSnapshotRefreshBackgroundTask) {
let expireDate = Date(timeIntervalSinceNow: 30 * 60) // 30 minutes
let userInfo = ["lastActiveDate" : Date()]
let restoredDefaultState = false
snapTask.setTaskCompleted(restoredDefaultState: restoredDefaultState,
estimatedSnapshotExpiration: expireDate,
userInfo: userInfo)
}
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up Fetch Data Update Model Update UI
Football scoresWalkthrough
7:30 PM 7:35 PM
Wake Up Fetch Data Update Model Update UI
5 seconds 5 seconds 5 seconds
Scheduling
Austen Green watchOS Engineer
RuntimeScheduling
RuntimeScheduling
Always scheduled in foreground
RuntimeScheduling
Always scheduled in foregroundUsually suspended in background
RuntimeScheduling
Always scheduled in foregroundUsually suspended in backgroundTargeted runtime for specific tasks
Runtime limitsScheduling
Runtime limitsScheduling
On order of seconds
Runtime limitsScheduling
On order of seconds• Time and CPU considered
Runtime limitsScheduling
On order of seconds• Time and CPU considered• Apps killed for exceeding limits
- CPU - 0xc51bad01- Time - 0xc51bad02
Runtime limitsScheduling
On order of seconds• Time and CPU considered• Apps killed for exceeding limits
- CPU - 0xc51bad01- Time - 0xc51bad02
Different allocations by taskWKApplicationRefreshBackgroundTask
WKURLSessionRefreshBackgroundTask
ComplicationsScheduling
ComplicationsScheduling
Multiple updates per hour
ComplicationsScheduling
Multiple updates per hourRequest updates through WKExtension
ComplicationsScheduling
Multiple updates per hourRequest updates through WKExtension50 guaranteed pushes
// Scheduling
// Complications
func modelChangedOniPhone() { let session = WCSession.defaultSession() let transfers = session.remainingComplicationUserInfoTransfers let userInfo // Complication data switch transfers { case 0: // No transfers left. Can still try to send session.transferCurrentComplicationUserInfo(userInfo) break; case 1...10: // Running low on transfers // Conditionally send if it's really important // Otherwise conserve the transfer for a more significant change break; default: // Send data immediately session.transferCurrentComplicationUserInfo(userInfo) } }
NEW
// Scheduling
// Complications
func modelChangedOniPhone() { let session = WCSession.defaultSession() let transfers = session.remainingComplicationUserInfoTransfers let userInfo // Complication data switch transfers { case 0: // No transfers left. Can still try to send session.transferCurrentComplicationUserInfo(userInfo) break; case 1...10: // Running low on transfers // Conditionally send if it's really important // Otherwise conserve the transfer for a more significant change break; default: // Send data immediately session.transferCurrentComplicationUserInfo(userInfo) } }
NEW
// Scheduling
// Complications
func modelChangedOniPhone() { let session = WCSession.defaultSession() let transfers = session.remainingComplicationUserInfoTransfers let userInfo // Complication data switch transfers { case 0: // No transfers left. Can still try to send session.transferCurrentComplicationUserInfo(userInfo) break; case 1...10: // Running low on transfers // Conditionally send if it's really important // Otherwise conserve the transfer for a more significant change break; default: // Send data immediately session.transferCurrentComplicationUserInfo(userInfo) } }
NEW
// Scheduling
// Complications
func modelChangedOniPhone() { let session = WCSession.defaultSession() let transfers = session.remainingComplicationUserInfoTransfers let userInfo // Complication data switch transfers { case 0: // No transfers left. Can still try to send session.transferCurrentComplicationUserInfo(userInfo) break; case 1...10: // Running low on transfers // Conditionally send if it's really important // Otherwise conserve the transfer for a more significant change break; default: // Send data immediately session.transferCurrentComplicationUserInfo(userInfo) } }
NEW
// Scheduling
// Complications
func modelChangedOniPhone() { let session = WCSession.defaultSession() let transfers = session.remainingComplicationUserInfoTransfers let userInfo // Complication data switch transfers { case 0: // No transfers left. Can still try to send session.transferCurrentComplicationUserInfo(userInfo) break; case 1...10: // Running low on transfers // Conditionally send if it's really important // Otherwise conserve the transfer for a more significant change break; default: // Send data immediately session.transferCurrentComplicationUserInfo(userInfo) } }
NEW
// Scheduling
// CLKComplicationDataSource
optional public func getNextRequestedUpdateDate(handler handler: (NSDate?) -> Void)
// Scheduling
// WKExtension
public func scheduleBackgroundRefresh(withPreferredDate preferredFireDate: Date,
userInfo: NSSecureCoding?, scheduledCompletion: (NSError?) -> Swift.Void)
// Scheduling
// CLKComplicationDataSource
optional public func requestedUpdateDidBegin()
// Scheduling
// WKExtensionDelegate
optional public func handle(_ backgroundTasks: Set<WKRefreshBackgroundTask>)
Dock appsScheduling
Dock appsScheduling
Minimum one per hour
Dock appsScheduling
Minimum one per hourDistributed budget
Dock appsScheduling
Minimum one per hourDistributed budget
Dock appsScheduling
Minimum one per hourDistributed budgetKept in memory
Recent appScheduling
Recent appScheduling
Most Recently Used app in dock
Recent appScheduling
Most Recently Used app in dock• Treated like a favorite app
Recent appScheduling
Most Recently Used app in dock• Treated like a favorite app
Home screen apps should not expect regular scheduling
System snapshotsScheduling
System snapshotsScheduling
Does not count against budget
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshot
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers• Complication timeline update
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers• Complication timeline update• Notification interaction
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers• Complication timeline update• Notification interaction• Foreground –> Background
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers• Complication timeline update• Notification interaction• Foreground –> Background• “Default state” one hour after backgrounding
System snapshotsScheduling
Does not count against budgetIn addition to app-requested snapshotTriggers• Complication timeline update• Notification interaction• Foreground –> Background• “Default state” one hour after backgrounding• Boot
Best Practices
Best Practices
Best Practices
Schedule as often as needed
Best Practices
Schedule as often as neededDo not feel obligated to do work • Finish ASAP• Defer work
Best Practices
Schedule as often as neededDo not feel obligated to do work • Finish ASAP• Defer work
Consider all runtime opportunities• Dock and foreground activations• Notifications• Complication updates• Background refresh
WKApplicationRefreshBackgroundTaskBest Practices
WKApplicationRefreshBackgroundTaskBest Practices
Use scheduleBackgroundRefresh for general-purpose runtime
WKApplicationRefreshBackgroundTaskBest Practices
Use scheduleBackgroundRefresh for general-purpose runtime• Polling
WKApplicationRefreshBackgroundTaskBest Practices
Use scheduleBackgroundRefresh for general-purpose runtime• Polling• Scheduling future NSURLSessions
WKApplicationRefreshBackgroundTaskBest Practices
Use scheduleBackgroundRefresh for general-purpose runtime• Polling• Scheduling future NSURLSessions• Known time transitions
WKApplicationRefreshBackgroundTaskBest Practices
Use scheduleBackgroundRefresh for general-purpose runtime• Polling• Scheduling future NSURLSessions• Known time transitions• Triggering complication updates
SnapshotsBest Practices
SnapshotsBest Practices
Invalidate snapshots appropriately
SnapshotsBest Practices
Invalidate snapshots appropriately“Significant content change”
SnapshotsBest Practices
Invalidate snapshots appropriately“Significant content change”Avoid high-frequency invalidation
Data flowBest Practices
Data flowBest Practices
External Event
Data flowBest Practices
External Event
Model
Data flowBest Practices
UpdateComplication
External Event
Request Snapshot Request Background URL Session
Schedule Background Refresh
Model
App lifecycleBest Practices
App lifecycleBest Practices
Finish background tasks ASAP on foreground activation
App lifecycleBest Practices
Finish background tasks ASAP on foreground activationFinish foreground work when entering background
App lifecycleBest Practices
Finish background tasks ASAP on foreground activationFinish foreground work when entering backgroundNSProcessInfo.performExpiringActivity
App lifecycleBest Practices
Finish background tasks ASAP on foreground activationFinish foreground work when entering backgroundNSProcessInfo.performExpiringActivity
WatchKit Tips and Tricks WWDC 2015
App lifecycleBest Practices
Finish background tasks ASAP on foreground activationFinish foreground work when entering backgroundNSProcessInfo.performExpiringActivity
Data protection
WatchKit Tips and Tricks WWDC 2015
TestingBest Practices
TestingBest Practices
Simulator for iterative development
TestingBest Practices
Simulator for iterative developmentKeep the device on charger
TestingBest Practices
Simulator for iterative developmentKeep the device on chargerTest the launch path
TestingBest Practices
Simulator for iterative developmentKeep the device on chargerTest the launch pathVerify tasks are being completed
TestingBest Practices
Simulator for iterative developmentKeep the device on chargerTest the launch pathVerify tasks are being completedLive on it
TestingBest Practices
Simulator for iterative developmentKeep the device on chargerTest the launch pathVerify tasks are being completedLive on it• Vary number of apps in the dock
StocksCase Study
StocksCase Study
StocksCase Study
Characteristics
StocksCase Study
Characteristics• NSURLSession to retrieve server data
StocksCase Study
Characteristics• NSURLSession to retrieve server data• Has a complication
StocksCase Study
Characteristics• NSURLSession to retrieve server data• Has a complication• Periodic cadence for part of the day
StocksCase Study
Characteristics• NSURLSession to retrieve server data• Has a complication• Periodic cadence for part of the day• No updates while markets are closed
Case Study
Boot
Case Study
Boot• Load last data for snapshot
Case Study
Boot• Load last data for snapshot• Schedule a background NSURLSession
Case Study
Boot• Load last data for snapshot• Schedule a background NSURLSession• Use NSURLSessionDownloadTask
Case Study
Boot• Load last data for snapshot• Schedule a background NSURLSession• Use NSURLSessionDownloadTask• NSURLSessionDataTask will fail for
background session on app suspension
Case Study
NSURLSession
Case Study
NSURLSession• Update model
Case Study
NSURLSession• Update model
- Trigger a complication update
Case Study
NSURLSession• Update model
- Trigger a complication update- Request a new snapshot for now
Case Study
NSURLSession• Update model
- Trigger a complication update- Request a new snapshot for now- Request a background refresh for next
expected model update time
Case Study
Background refresh
Case Study
Background refresh• Schedule the next NSURLSession download
Stocks activated from the dock
Case Study
Stocks activated from the dock• Use NSURLSession to update model
Case Study
Stocks activated from the dock• Use NSURLSession to update model
- Request complication update
Case Study
Stocks activated from the dock• Use NSURLSession to update model
- Request complication update- Request new snapshot
Case Study
Stocks activated from the dock• Use NSURLSession to update model
- Request complication update- Request new snapshot- Schedule background refresh for a
later time
Case Study
Case Study
Last update after market close
Case Study
Last update after market close• Data has stopped changing for the day
Case Study
Last update after market close• Data has stopped changing for the day
- Complete update as normal
Case Study
Last update after market close• Data has stopped changing for the day
- Complete update as normal- Schedule next refresh for market open
Summary
Summary
Complete your tasks
Summary
Complete your tasksUse runtime efficiently
Summary
Complete your tasksUse runtime efficientlyTell the system when data changes
Summary
Complete your tasksUse runtime efficientlyTell the system when data changesConsider adoption strategies on case-by-case basis
More Information
https://developer.apple.com/wwdc16/218
What’s New in watchOS 3 Presidio Tuesday 5:00PM
Quick Interaction Techniques for watchOS Presidio Wednesday 11:00AM
Designing Great Apple Watch Experiences Presidio Wednesday 1:40PM
Architecting for Performance on watchOS 3 Mission Thursday 3:00PM
Related Sessions
Labs
WatchKit and Background Tasks Lab Frameworks Lab C Thursday 10:30AM
WatchKit and WatchConnectivity Lab Frameworks Lab B Friday 2:00PM
