App Extension Best Practices - Apple Inc. · App Extension Best Practices Sophia Teutschler UIKit Engineer Ian Baird CoreOS Engineer App Frameworks Session 224. Agenda. Agenda Action

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App Extension Best Practices

Sophia Teutschler UIKit EngineerIan Baird CoreOS Engineer

App Frameworks

Session 224

Agenda

Agenda

Action and Share Extensions

Agenda

Action and Share ExtensionsToday widget enhancements

Agenda

Action and Share ExtensionsToday widget enhancementsReal world examples



ShareAction

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Action and Share ExtensionsAction Extensions

Action

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Acts on the current content

Action

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Acts on the current contentUses the content as the user interface

Action

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Acts on the current contentUses the content as the user interfaceOpportunity to present additional options

Action

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Acts on the current contentUses the content as the user interfaceOpportunity to present additional optionsApp can provide multiple Action Extensions

Action

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ShareAction

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Share

Action and Share ExtensionsShare Extensions

Share


Shares content to your app or web service

Share


Shares content to your app or web serviceAllows validation and editing

Share


Shares content to your app or web serviceAllows validation and editingCan use SLComposeServiceViewController

Share


Shares content to your app or web serviceAllows validation and editingCan use SLComposeServiceViewControllerYour app provides one Share Extension

Share

Action and Share ExtensionsSLComposeServiceViewController



viewController.placeholder = "Caption (Optional)"


viewController.placeholder = "Caption (Optional)"


viewController.charactersRemaining = 80


viewController.charactersRemaining = 80

override func loadPreviewView() -> UIView! { return FaceDetectingPreviewView(…) }


override func loadPreviewView() -> UIView! { return FaceDetectingPreviewView(…) }



func configurationItems() -> [SLComposeSheetConfigurationItem]


func configurationItems() -> [SLComposeSheetConfigurationItem]


override func configurationItems() -> [AnyObject]! { let item = SLComposeSheetConfigurationItem()

item.title = "Blog" item.value = "My Road Trips"

item.tapHandler = { let viewController = BlogPickerViewController() self.pushConfigurationViewController(viewController) }

return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }





return [ item ] }


viewController.autocompletionViewController = SuggestionViewController(…)


viewController.autocompletionViewController = SuggestionViewController(…)



Provides consistent and familiar UI


Provides consistent and familiar UICustomizable


Provides consistent and familiar UICustomizableCompletely custom UI using UIViewController

Action and Share ExtensionsBeing a good host

kUTTypePlainText


kUTTypePDF


kUTTypeHTML



kUTTypeHTMLkUTTypePDFkUTTypePlainText

NSItemProvider


kUTTypePlainText kUTTypePDF kUTTypeHTML


let itemProvider = NSItemProvider()

itemProvider.registerItemForTypeIdentifier(kUTTypePlainText as String) { completionHandler, expectedClass, options in completionHandler(self.renderPlainTextDocumentString(), nil) }

itemProvider.registerItemForTypeIdentifier(kUTTypePDF as String) { completionHandler, expectedClass, options in completionHandler(self.renderPDFDocument(), nil) }

let vc = UIActivityViewController(activityItems: [ itemProvider ], applicationActivities: nil) self.presentViewController(vc, animated: true, completion: nil)
















































Host apps should offer content previews


Host apps should offer content previews• Represents what will be shared


Host apps should offer content previews• Represents what will be shared• Simple and efficient representation of the content


itemProvider.previewImageHandler = { completionHandler, expectedClass, options in completionHandler(self.renderThumbnail(), nil) }







Action and Share ExtensionsActivation rules


Host App

kUTTypeMovie

kUTTypeImage


NSExtensionActivationSupportsImage

NSExtensionActivationSupportsMovie



Extension

Extension

Extension

Host App

kUTTypeMovie

kUTTypeImage


Host App

kUTTypeMovie

kUTTypeImage





Extension

Extension

Extension


Host App

kUTTypeMovie

kUTTypeImage





Extension

Extension

Extension






Extension

Extension

Extension

Host App

kUTTypeMovie

kUTTypeImage









Extension

Extension

Extension

Host App

kUTTypeMovie

kUTTypeImage


SUBQUERY(extensionItems, $extensionItem, SUBQUERY($extensionItem.attachments, $attachment, ANY $attachment.registeredTypeIdentifiers UTI-CONFORMS-TO "public.image").@count == 1).@count == 1 OR SUBQUERY(extensionItems, $extensionItem, SUBQUERY($extensionItem.attachments, $attachment, ANY $attachment.registeredTypeIdentifiers UTI-CONFORMS-TO "com.adobe.pdf").@count == 1).@count == 1


SUBQUERY(extensionItems, $extensionItem, SUBQUERY($extensionItem.attachments, $attachment, ANY $attachment.registeredTypeIdentifiers UTI-CONFORMS-TO "public.image").@count == 1).@count == 1 OR SUBQUERY(extensionItems, $extensionItem, SUBQUERY($extensionItem.attachments, $attachment, ANY $attachment.registeredTypeIdentifiers UTI-CONFORMS-TO "com.adobe.pdf").@count == 1).@count == 1

Action and Share ExtensionsIcons


Share Extensions use the containing app icon


Share Extensions use the containing app icon• No additional work needed



Action Extensions require template images


Action Extensions require template images• Two sizes for iPhone and iPad


Action Extensions require template images• Two sizes for iPhone and iPad• Reside in the extension bundle


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Action and Share ExtensionsAction icons

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76pt60pt

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76pt60pt29pt 40pt

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Today Widget Enhancements

Ian Baird CoreOS Engineer


Quick information at a glance


Quick information at a glanceEnhance your Today widget


Quick information at a glanceEnhance your Today widgetGeneral best practices

Working with the Containing AppURL handlers

Interactions use URLs to take user to app


Interactions use URLs to take user to appBest practices


Interactions use URLs to take user to appBest practices• Use your app’s registered URL schemes


Interactions use URLs to take user to appBest practices• Use your app’s registered URL schemes• System URL schemes


Interactions use URLs to take user to app.Best practices• Use your app’s registered URL schemes• System URL schemes

func tableView(…, didSelectRowAtIndexPath indexPath: NSIndexPath) { let selectedName = names[indexPath.row] let URL = NSURL(string: "my-app://name=\(selectedName)")! extensionContext!.openURL(URL) { success in print("openURL returned: \(success)") } }










Working with the Containing AppApp groups

Defaults


DefaultsContainers


DefaultsContainersKeychain items


DefaultsContainersKeychain itemsFramework data

Working with the Containing AppUser defaults


Used for small pieces of configuration data


Used for small pieces of configuration data

let defaults = NSUserDefaults.initWithSuiteName("group.com.example.my-app")

Working with the Containing AppWhat goes in a shared container?

Model data


Model dataDocuments


Model dataDocumentsMedia

Working with the Containing AppWorking with model data in the shared container

lazy var secureAppGroupPersistentStoreURL: NSURL = { let fm = NSFileManager.defaultManager() let directory = fm.containerURLForSecurityApplicationGroupIdentifier("group.com.example.my-app")! return directory.URLByAppendingPathComponent("myFileName.sqlite") }()










lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = { let storeCoordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel) let storeURL = self.secureAppGroupPersistentStoreURL do { try storeCoordinator.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: storeURL, options: [NSMigratePersistentStoresAutomaticallyOption: true, NSInferMappingModelAutomaticallyOption, true]) } catch let error as NSError { // handle error } return storeCoordinator }()












lazy var managedObjectContext: NSManagedObjectContext = { let coordinator = self.persistentStoreCoordinator var managedObjectContext = NSManagedObjectContext(concurrencyType: .MainQueueConcurrencyType) managedObjectContext.persistentStoreCoordinator = coordinator return managedObjectContext }()







Staying ResponsiveLocking in the shared container


Be careful taking exclusive locks for data in the shared container


Be careful taking exclusive locks for data in the shared containerExtension killed if it’s suspended while holding an exclusive lock

Staying ResponsiveTask assertions

Extensions suspended when no longer in use


Extensions suspended when no longer in useProtect serialization and other clean-up tasks with background task assertions


let pi = NSProcessInfo.processInfo() pi.performExpiringActivityWithReason("clean-up") { expired in if (!expired) { self.serializeData() } else { self.cleanupSerializingData() } }









expired == false



expired == false –> perform protected task



expired == true



expired == true -> cancel protected task



exit the block -> task assertion is released



expired == true



expired == true -> cancel any work and exit the block


Released when your code exits the block


Released when your code exits the blockRe-entrant execution of callback for expiration


Released when your code exits the blockRe-entrant execution of callback for expirationTask assertions are not always available for your extension

Staying ResponsiveWorking with other queues

Task assertion scoped to callback block


Task assertion scoped to callback blockCallback block must synchronize with protected work on other queues


Task assertion scoped to callback blockCallback block must synchronize with protected work on other queuesExample


Task assertion scoped to callback blockCallback block must synchronize with protected work on other queuesExample• Dispatch block to the main queue

Staying ResponsiveWorking with the main queue

let pi = NSProcessInfo.processInfo() pi.performExpiringActivityWithReason("clean-up") { expired in if (!expired) { dispatch_async(dispatch_get_main_queue(), { self.performInterruptibleWork() }) } else { self.canceled = true } }


let pi = NSProcessInfo.processInfo() pi.performExpiringActivityWithReason("clean-up") { expired in if (!expired) { dispatch_async(dispatch_get_main_queue(), { self.performInterruptibleWork() }) } else { self.canceled = true } }


let pi = NSProcessInfo.processInfo() pi.performExpiringActivityWithReason("clean-up") { expired in if (!expired) { dispatch_sync(dispatch_get_main_queue(), { self.performInterruptibleWork() }) } else { self.canceled = true } }





Callback block is executing on a private system queue

Staying Up to DateDarwin Notification Center

Similar to NSNotificationCenter


Similar to NSNotificationCenter


Similar to NSNotificationCenterSmall number of use-cases


Similar to NSNotificationCenterSmall number of use-casesExample


Similar to NSNotificationCenterSmall number of use-casesExample• Hint to your extension to reload the model

Staying Up to DateContaining app API

let nc = CFNotificationCenterGetDarwinNotifyCenter() CFNotificationCenterPostNotification(nc, "com.example.app-model-updated", nil, nil, CFBooleanGetValue(true))







Staying Up to DateExtension API

let nc = CFNotificationCenterGetDarwinNotifyCenter() CFNotificationCenterAddObserver(nc, nil, { _ in self.reloadModel() }, "com.example.app-model-updated", nil, .DeliverImmediately)









Background RefreshKeeping your widget up to date

Background Refresh

Background Refresh

AAPL: $132.12

Background RefreshUpdating the widget

System opportunistically refreshes content


System opportunistically refreshes contentView controller conforms to NCWidgetProviding


System opportunistically refreshes contentView controller conforms to NCWidgetProvidingImplements update delegate method



func widgetPerformUpdateWithCompletionHandler(completionHandler: ((NCUpdateResult) -> Void)) { let updated = refreshTheModel() if (updated) { view.setNeedsDisplay() } completionHandler(updated ? .NewData : .NoData) }













NetworkingBackground sessions

NetworkingNSURLSession

Background sessions


Background sessionsTask performed by the system


Background sessionsTask performed by the systemUpdates delivered to your extension as long as it stays alive


Background sessionsTask performed by the systemUpdates delivered to your extension as long as it stays aliveError and event handled by the containing app


Background sessionsTask performed by the systemUpdates delivered to your extension as long as it stays aliveError and event handled by the containing app

NetworkingExtension API

let sc = NSURLSessionConfiguration.backgroundSessionConfigurationWithIdentifier( "com.example.my-download-session") sc.sharedContainerIdentifier = "group.com.example.my-app" let session = NSURLSession(configuration: sc, delegate: self, delegateQueue: NSOperationQueue.mainQueue()) let request = NSURLRequest(URL: NSURL(string: "https://www.apple.com/")!) let task = session.downloadTaskWithRequest(request) task?.resume()






let sc = NSURLSessionConfiguration.backgroundSessionConfigurationWithIdentifier( "com.example.my-download-session") sc.sharedContainerIdentifier = "group.com.example.my-app" let session = NSURLSession(configuration: sc, delegate: self, delegateQueue: NSOperationQueue.mainQueue()) let request = NSURLRequest(URL: NSURL(string: “https://www.apple.com/")!) let task = session.downloadTaskWithRequest(request) task?.resume()







NetworkingContaining app API

func application(application: UIApplication, handleEventsForBackgroundURLSession identifier: String, completionHandler: () -> Void) { guard (identifier == "com.example.my-download-session") else { return } let sc = NSURLSessionConfiguration.backgroundSessionConfigurationWithIdentifier(identifier) sc.sharedContainerIdentifier = "group.com.example.my-app" self.session = NSURLSession(configuration: sc, delegate: self, delegateQueue: NSOperationQueue.mainQueue()) self.completionHandler = completionHandler }












func URLSessionDidFinishEventsForBackgroundURLSession(session: NSURLSession){ let sc = session.configuration guard (sc.identifier == "com.example.my-download-session") else { return } self.completionHandler!() self.session = nil }









NetworkingwatchOS

Use background task assertions to protect small tasks

NetworkingwatchOS

Use background task assertions to protect small tasks

WatchKit Tips and Tricks Presidio Friday 10:00AM

Sharing Secretskeychain-access-groups entitlement

Sharing SecretsAPI

// Add an item SecItemAdd({ kSecAttrAccessGroup: "com.example.your-app-group"}, result: NULL)

Sharing SecretsAPI


Sharing SecretsAPI


Sharing SecretsAPI

Automatic search behavior for query API

Security and Your Apps Mission Tuesday 4:30PM

Sharing SecretsAPI

Automatic search behavior for query API• SecItemUpdate


Sharing SecretsAPI

Automatic search behavior for query API• SecItemUpdate• SecItemDelete


Sharing SecretsAPI

Automatic search behavior for query API• SecItemUpdate• SecItemDelete• SecItemCopyMatching


Sharing SecretsAPI

Automatic search behavior for query API• SecItemUpdate• SecItemDelete• SecItemCopyMatching


Summary


Summary

Action and Share ExtensionsEnhanced Today widget

Summary

Action and Share ExtensionsEnhanced Today widgetGeneral best practices

Related Sessions

WatchKit Tips and Tricks Presidio Friday 10:00AM


More Information

DocumentationApp Extension Programming Guide

Sample CodeListerSample Photo Editing Extensionhttp://developer.apple.com/app-extensions

Technical SupportApple Developer ForumsDeveloper Technical Supporthttp://devforums.apple.com

General InquiriesCurt Rothert, App Frameworks [email protected]

mailto:[email protected]