iOS DispatchQueue.main.sync not working Swift 4 Xcode 9 - swift4

I am trying to get TouchID to authenticate an action on my app. I need it to show an ImageView if successful.
Here is the code that I have in the ViewController
#IBOutlet weak var notificationImage: UIImageView!
#IBAction func touchBtn(_ sender: UIButton) {
context = LAContext()
var error: NSError?
if context.canEvaluatePolicy(.deviceOwnerAuthentication, error: &error) {
let reason = "Authenticate"
context.evaluatePolicy(.deviceOwnerAuthentication, localizedReason: reason ) { success, error in
if success {
print("In closure")
// Move to the main thread because a state update triggers UI changes.
DispatchQueue.main.async{
print("In main thread: Success")
self.notificationImage.isHidden = false
}
} else {
DispatchQueue.main.async(execute: {
print("In main thread: Failed")
})
}
}
}
}
I am able to successfully authenticate using TouchID. It prints "In closure". But the block in the DispatchQueue.main.async does not execute and I am unable to update the notificationImage: UIImageView. Neither does it print anything in the sync{} blocks.
I have tried to disable Main Thread Checker and removing the DispatchQueue.main.async part, but the view sometimes refreshes and sometimes it doesn't. I want to use the recommended practice and update the UI from the main thread.
I am on Xcode 9 Swift 4 iOS 11.4
What could be wrong here.

try this code
#IBAction func touchBtn(_ sender: UIButton) {
let context = LAContext()
var error: NSError?
if context.canEvaluatePolicy(.deviceOwnerAuthentication, error: &error) {
let reason = "Authenticate"
context.evaluatePolicy(.deviceOwnerAuthentication, localizedReason: reason ) { success, error in
if success {
do {
print("In closure")
print("In main thread: Success")
self.notificationImage.isHidden = false
} catch let error as NSError {
print(error.localizedDescription)
print(error.description)
}
} else {
DispatchQueue.main.async(execute: {
print("In main thread: Failed")
})
}
}
}
}

Related

I can detect workout started on backgroun with apple watch, but how can I detect workout finished?

I can detect workout started on backgroun with apple watch, with below code
let workoutevent = HKObjectType.workoutType()
if store.authorizationStatus(for: workoutevent) != HKAuthorizationStatus.notDetermined {
store.enableBackgroundDelivery(for: workoutevent, frequency: .immediate, withCompletion: { (worked, error) in
print(worked)
print(error)
print("workoutevent enableBackgroundDelivery")
guard worked else {
self.logger.error("Unable to set up background delivery from HealthKit: \(error!.localizedDescription)")
print("workoutevent unable to set up background ")
fatalError()
}
if error != nil {
print("workoutevent error is ")
print(error)
}
})
backgroundObserver3 =
HKObserverQuery(sampleType: workoutevent,
predicate: nil,
updateHandler: processUpdate3(query:completionHandler3:error:))
if let queryworkout = backgroundObserver3 {
print("Starting workoutevent333 the background observer query.\(queryworkout)")
store.execute(queryworkout)
}
}else{
print("not determined....")
}
whenever I started workout on apple watch, it goes to
processUpdate3
very well,
but what I need to know is to when user finish workout.
how can I detect it ?
func processUpdate3(query: HKObserverQuery,
completionHandler3: #escaping () -> Void,
error: Error?) {
print("come here when work out started ")
...........
}
I don't see it in your code. But somewhere you must have an HKWorkoutSession. My app is set up to track running and I configure the session to begin like so;
let configuration = HKWorkoutConfiguration()
configuration.activityType = .running
do {
// HKWorkoutSession is set up here.
session = try HKWorkoutSession(healthStore: healthStore, configuration: configuration)
workoutBuilder = session.associatedWorkoutBuilder()
} catch {
// handle errors
}
When the users taps the end workout button I call session.end()
Here is a link to the documentation.

Background thread Core Data object property changes doesn't reflect on UI

Let say I want to add a new item in Playlist entity of CoreData and put it in background thread and push back it to main thread then reflect it on tableView. Well, that code is working fine without background thread implementation.
But when I apply below background kinda code, after createPlaylist is executed, tableView becomes to empty space(without any items showed up), though print(self?.playlists.count) gives the correct rows count.
When dealing with GCD, I put some heavy code in background queue and push back to main queue for UI update in same closure. But it seems not worked here, I google a quit of time but still cannot anchor the issue.
import UIKit
import CoreData
class PlayListViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var songs = [Song]()
var position = 0
let container = (UIApplication.shared.delegate as! AppDelegate).persistentContainer
private var playlists = [Playlist]()
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = UIColor(white: 1, alpha: 1)
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "playlistCell")
configureLayout()
getAllPlaylists()
}
// MARK: Core data functions
func getAllPlaylists() {
do {
let context = self.container.viewContext
playlists = try context.fetch(Playlist.fetchRequest())
DispatchQueue.main.async { [weak self] in
self?.tableView.reloadData()
}
print("count: \(playlists.count)")
// printThreadStats()
} catch {
print("getAllPlaylists failed, \(error)")
}
}
func createPlaylist(name: String) {
container.performBackgroundTask { context in
let newPlaylist = Playlist(context: context)
newPlaylist.name = name
do {
try context.save()
self.playlists = try context.fetch(Playlist.fetchRequest())
DispatchQueue.main.async { [weak self] in
self?.tableView.reloadData()
print(self?.playlists.count)
}
} catch {
print("Create playlist failed, \(error)")
}
}
}
// MARK: tableView data source implementation
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return playlists.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let playlist = playlists[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "playlistCell", for: indexPath)
cell.textLabel?.text = playlist.name
// cell.detailTextLabel?.text = "2 songs"
return cell
}
auto generated fetchRequest and Property defining
import Foundation
import CoreData
extension Playlist {
#nonobjc public class func fetchRequest() -> NSFetchRequest<Playlist> {
return NSFetchRequest<Playlist>(entityName: "Playlist")
}
#NSManaged public var name: String?
}
For the first call of func getAllPlaylists(), you are calling this on main thread from viewDidLoad(). So following lines are executed on main thread.
let context = self.container.viewContext
playlists = try context.fetch(Playlist.fetchRequest())
Next time inside the createPlaylist method, you are performing add playlist task in background context (not on main thread). So following lines are executed on background thread.
self.playlists = try context.fetch(Playlist.fetchRequest())
Also note that, first time we are using viewContext to fetch playlists and second time a backgroundContext. This mix up causes the UI to not show expected result.
I think these two methods could be simplified to -
func getAllPlaylists() {
do {
let context = self.container.viewContext
playlists = try context.fetch(Playlist.fetchRequest())
// DispatchQueue.main.async not necessary, we are already on main thread
self.tableView.reloadData()
print("count: \(playlists.count)")
} catch {
print("getAllPlaylists failed, \(error)")
}
}
func createPlaylist(name: String) {
container.performBackgroundTask { context in
let newPlaylist = Playlist(context: context)
newPlaylist.name = name
do {
try context.save()
DispatchQueue.main.async { [weak self] in
self?.getAllPlaylists()
}
} catch {
print("Create playlist failed, \(error)")
}
}
}
After 5 hours' digging today, I found the solution. I'd like put my solution and code below, because the stuff about "How to pass NSManagedObject instances between queues in CoreData" is quite rare && fragmentation, not friendly to newbies of SWIFT.
The thing is we want to do heavy CoreData task on background thread and reflect the changes in UI on foreground(main thread). Generally, we need to create a private queue context(privateMOC) and perform the heavy CoreData task on this private context, see below code.
For reuse purpose, I put CoreData functions separately.
import UIKit
import CoreData
struct CoreDataManager {
let managedObjectContext: NSManagedObjectContext
private let privateMOC = NSManagedObjectContext(concurrencyType: .privateQueueConcurrencyType)
let coreDataStack = CoreDataStack()
static let shared = CoreDataManager()
private init() {
self.managedObjectContext = coreDataStack.persistentContainer.viewContext
privateMOC.parent = self.managedObjectContext
}
func fetchAllPlaylists(completion: #escaping ([Playlist]?) -> Void) {
privateMOC.performAndWait {
do {
let playlists: [Playlist] = try privateMOC.fetch(Playlist.fetchRequest())
print("getAllPlaylists")
printThreadStats()
print("count: \(playlists.count)")
completion(playlists)
} catch {
print("fetchAllPlaylists failed, \(error), \(error.localizedDescription)")
completion(nil)
}
}
}
func createPlaylist(name: String) {
privateMOC.performAndWait {
let newPlaylist = Playlist(context: privateMOC)
newPlaylist.name = name
synchronize()
}
}
func deletePlaylist(playlist: Playlist) {
privateMOC.performAndWait {
privateMOC.delete(playlist)
synchronize()
}
}
func updatePlaylist(playlist: Playlist, newName: String) {
...
}
func removeAllFromEntity(entityName: String) {
...
}
func synchronize() {
do {
// We call save on the private context, which moves all of the changes into the main queue context without blocking the main queue.
try privateMOC.save()
managedObjectContext.performAndWait {
do {
try managedObjectContext.save()
} catch {
print("Could not synchonize data. \(error), \(error.localizedDescription)")
}
}
} catch {
print("Could not synchonize data. \(error), \(error.localizedDescription)")
}
}
func printThreadStats() {
if Thread.isMainThread {
print("on the main thread")
} else {
print("off the main thread")
}
}
}
And Apple has a nice template for it Using a Private Queue to Support Concurrency
Another helpful link: Best practice: Core Data Concurrency
The real tricky thing is how to connect it with your view or viewController, the really implementation. See below ViewController code.
// 1
override func viewDidLoad() {
super.viewDidLoad()
// some layout code
// execute on background thread
DispatchQueue.global().async { [weak self] in
self?.fetchAndReload()
}
}
// 2
private func fetchAndReload() {
CoreDataManager.shared.fetchAllPlaylists(completion: { playlists in
guard let playlists = playlists else { return }
self.playlists = playlists
})
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
// 3
#objc func createNewPlaylist(_ sender: Any?) {
let ac = UIAlertController(title: "Create New Playlist", message: "", preferredStyle: .alert)
ac.addTextField { textField in
textField.placeholder = "input your desired name"
}
ac.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
ac.addAction(UIAlertAction(title: "Done", style: .default, handler: { [weak self] _ in
guard let textField = ac.textFields?.first, let newName = textField.text, !newName.isEmpty else { return }
// check duplicate
if let playlists = self?.playlists {
if playlists.contains(where: { playlist in
playlist.name == newName
}) {
self?.duplicateNameAlert()
return
}
}
DispatchQueue.global().async { [weak self] in
CoreDataManager.shared.createPlaylist(name: newName)
self?.fetchAndReload()
}
}))
present(ac, animated: true)
}
Let me break down it:
First in viewDidload, we call fetchAndReload on background thread.
In fetchAndReload function, it brings out all the playlist(returns data with completion handler) and refresh the table on main thread.
We call createPlaylist(name: newName) in background thread and reload the table on main thread again.
Well, this is the 1st time I deal with Multi-threading in CoreData, if there is any mistake, please indicate it. Allright, that's it! Hope it could help someone.

CLSLogv logs are not coming in Crashlytics

Its an Ionic app with some code written in native. Its uses cordova-plugin-firebase that for logging Crashlytics.
In the native part for iOS as well, we are trying to use Crashlytics to enable logging. However no matter what I try logs sent using CLSLogv aren't visible in dashboard.
Here is my code.
#objc(ImageUpload) class ImageUpload : CDVPlugin {
var backgroundTask: UIBackgroundTaskIdentifier = UIBackgroundTaskInvalid
//https://docs.fabric.io/apple/crashlytics/enhanced-reports.html#custom-logging-in-swift
private func sendErrorToCrashlytics(error: String) {
NSLog("Error in send error function is \(error)")
CLSLogv("%#", getVaList([error]))
}
#objc(imageUpload:)
func imageUpload(command: CDVInvokedUrlCommand) {
registerBackgroundTask()
func execute() {
let db = SQLiteDatabase()
var recToUpLoad: PayloadModel? = nil
while(toCheck) {
do {
let record = try db.readValues() // THIS METHOD THROWS EXCEPTION
} catch Exceptions.SQLiteError(let error) {
self.sendErrorToCrashlytics(error: error) // IT COMES HERE AFTER EXCEPTION
}
}
}
DispatchQueue(label: "imageUploadPlugin",qos: .background).async
{
execute()
}
}
}
However CLSLogv is not visible at all in Crashlytics. However when I do Crashlytics.sharedInstance().throwException()
, I can see it in the dashboard.
Exceptions is enum
enum Exceptions: Error {
case SQLiteError(message: String)
case JSONError(message: String)
}
Hoping it may help someone. Somehow I couldn't get CLSLogv to work. I ended up creating an NSError object and log that in Crashlytics in catch block.
catch Exceptions.SQLiteError(let error) {
let userInfo = [NSLocalizedDescriptionKey: error.message, "query": error.query]
let errorObj = NSError(domain: "sqlite", code: 400, userInfo: userInfo)
Crashlytics.sharedInstance().recordError(errorObj)
}

Debugging advice for WatchOS2

I've been going through the examples in WatchOS 2 By Tutorial book by the team over at RayWenderlich, specifically chapter 18. They all work fine. In my own App, I am trying to send a button press from the watch to fire a button on the iPhone App. Here's the relevant code in Swift from the Watch and the Phone:
Watch:
//
// InterfaceController.swift
// Wasted Time Extension
//
// Created by Michael Rowe on 7/21/15.
// Copyright © 2010-2015 Michael Rowe. All rights reserved.
//
import WatchKit
import WatchConnectivity
import Foundation
class InterfaceController: WKInterfaceController,WCSessionDelegate {
#IBOutlet var wasteLabel: WKInterfaceLabel!
#IBOutlet var costLabel: WKInterfaceLabel!
#IBOutlet var counter: WKInterfaceLabel!
#IBOutlet var statusButton: WKInterfaceButton!
// our watchconnective session
var session : WCSession?
override func awakeWithContext(context: AnyObject?) {
super.awakeWithContext(context)
}
override func willActivate() {
// This method is called when watch view controller is about to be visible to user
super.willActivate()
if(WCSession.isSupported()){
session = WCSession.defaultSession()
session!.delegate = self
session!.activateSession()
}
}
override func didDeactivate() {
// This method is called when watch view controller is no longer visible
super.didDeactivate()
}
func session(session: WCSession, didReceiveMessage message: [String: AnyObject], replyHandler: [String: AnyObject] -> Void) {
print("Did receive message Watch \(message)")
}
#IBAction func addButtonPressed() {
// Pull values from the Phone for current meeting cost, waste costs, and people in meeting
let prefs:NSUserDefaults = NSUserDefaults(suiteName: "a.b.c")!
var counterd = prefs.doubleForKey("keyPeopleInMeeting")
counterd++
counter.setText(String(format:"%9.0f", counterd))
// Sending data to iPhone via Interactive Messaging
if WCSession.isSupported(){
// we have a watch supporting iPhone
let session = WCSession.defaultSession()
// we can reach the watch
if session.reachable {
let message = ["add": "1"]
print("Message \(message)")
session.transferUserInfo(message)
print("Send Message Add - People \(counterd)")
}
}
if WCSession.isSupported() {
let session = WCSession.defaultSession()
if session.reachable {
let message = ["add":"1"]
session.sendMessage(message, replyHandler: { ( reply: [String: AnyObject]) -> Void in
print("Reply: \(reply)")
}, errorHandler: { (error: NSError) -> Void in
print("ERROR Watch: \(error.localizedDescription)")
})
} else { // reachable
self.showReachabilityError()
}
}
print("Watch Add Button Pressed \(counterd)")
}
#IBAction func minusButtonPressed() {
// Pull values from the Phone for current meeting cost, waste costs, and people in meeting
let prefs:NSUserDefaults = NSUserDefaults(suiteName: "a.b.c")!
var counterd = prefs.doubleForKey("keyPeopleInMeeting")
counterd--
if (counterd <= 1) {
counterd = 1
}
counter.setText(String(format:"%9.0f", counterd))
if WCSession.isSupported() {
let session = WCSession.defaultSession()
if session.reachable {
let message = ["minus":"1"]
session.sendMessage(message, replyHandler: { ( reply: [String: AnyObject]) -> Void in
print("Reply: \(reply)")
}, errorHandler: { (error: NSError) -> Void in
print("ERROR Watch: \(error.localizedDescription)")
})
} else { // reachable
self.showReachabilityError()
}
}
print("Watch Minus Button Pressed \(counterd)")
}
func statusButtonPressed() {
// Pull values from the Phone for current meeting cost, waste costs, and people in meeting
let prefs:NSUserDefaults = NSUserDefaults(suiteName: "a.b.c")!
let status = statusButton.description
if WCSession.isSupported() {
let session = WCSession.defaultSession()
if session.reachable {
let message = ["status":status]
session.sendMessage(message, replyHandler: { ( reply: [String: AnyObject]) -> Void in
print("Reply: \(reply)")
}, errorHandler: { (error: NSError) -> Void in
print("ERROR Watch: \(error.localizedDescription)")
})
} else { // reachable
self.showReachabilityError()
}
}
print("Watch Status Button Pressed - Status \(statusButton)")
}
func session(session: WCSession, didReceiveApplicationContext applicationContext: [String : AnyObject]){
let prefs:NSUserDefaults = NSUserDefaults(suiteName: "a.b.c")!
if let waste = applicationContext["waste"] as? Float {
print("Watch Receive - Waste \(waste)")
}
if let cost = applicationContext["cost"] as? Float {
print("Watch Receive - Cost \(cost)")
}
if let counternum = applicationContext["counter"] as? Float {
print("Watch Receive - Counter \(counternum)")
}
if let status = applicationContext["status"] as? String {
print("Watch Receive - Status \(status)")
statusButton.setTitle(status)
}
}
private func showReachabilityError() {
let tryAgain = WKAlertAction(title: "Try Again", style: .Default, handler: { () -> Void in })
let cancel = WKAlertAction(title: "Cancel", style: .Cancel, handler: { () -> Void in })
self.presentAlertControllerWithTitle("Your iPhone is not reachable.", message: "You cannot adjust the status or number of attendees Watch is not currently connected to your iPhone. Please ensure your iPhone is on and within range of your Watch.", preferredStyle: WKAlertControllerStyle.Alert, actions:[tryAgain, cancel])
}
func session(session: WCSession, didFinishUserInfoTransfer userInfoTransfer: WCSessionUserInfoTransfer, error: NSError?) {
print("Transfer User Info Error watch: \(error)")
}
}
And the receiving code on the
iPhone:CODE:
func session(session: WCSession,
didReceiveMessage message: [String : AnyObject],
replyHandler: ([String : AnyObject]) -> Void) {
if let counterd = message["add"] as? Float {
let reply = ["add":counterd]
print("iPhone Receive Add \(counterd)")
addButtonPressed(self)
replyHandler(reply)
}
if let counterd = message["minus"] as? Float {
let reply = ["minus":counterd]
print("iPhone Receive minus \(counterd)")
removeButtonPressed(self)
replyHandler(reply)
}
if let status = message["status"] as? String {
if status == "Start" {
let reply = ["status":"Quorum"]
meetingStartedButtonPressed(self)
replyHandler(reply)
}
if status == "Quorum" {
let reply = ["status": "Finish"]
quorumButtonPressed(self)
replyHandler(reply)
}
if status == "Finish" {
let reply = ["status": "Reset"]
meetingEndedButtonPressed(self)
replyHandler(reply)
}
if status == "Reset" {
let reply = ["status": "Start"]
resetButtonPressed(self)
replyHandler(reply)
}
print("iPhone Received Status Button \(status)")
}
}
I get the messages firing fine on the Watch and see them in the debug log... But they do not seem to fire on the Phone. The phone is successfully sending its messages to the watch.
I have tested this code both in the simulator and on my own watch and iPhone. Note that the messages from the iPhone to the Watch are done using the via updateApplicationContext vs. the send message I am trying to use to send messages from the watch to the iPhone. Here's a sample of the iPhone code for sending context:
if WCSession.isSupported() {
if session.watchAppInstalled {
let UserInfo = ["waste":Float((wastedAmount.text! as NSString).floatValue), "cost":Float((totalAmount.text! as NSString).floatValue), "counter":Float((peopleInMeeting.text! as NSString).floatValue), "status":"Start"]
do {
try session.updateApplicationContext(UserInfo as! [String : AnyObject])
} catch {
print("Updating the context failed: ")
}
}
}
More information is needed regarding specifically what you're actually seeing on the Watch, when you say:
I get the messages firing fine on the Watch and see them in the debug log... But they do not seem to fire on the Phone. The phone is successfully sending its messages to the watch.
However, one common occurrence is that the iPhone code is actually working correctly, and the only thing you are not seeing is the debug statements printed to the console. This seems likely to be the case since you say you are seeing the expected Watch messages, presumably including those from print("Reply: \(reply)"). This indicates the message is being handled by the iPhone.
When that's the case, it's often simply that you are expecting to see debug console messages from both the Watch and iOS simulator processes at the same time, but in fact you're only connected to one or the other. There are (at least) two things you can do here:
Run the WatchKit app from Xcode, but then change to attach to the iPhone process instead. In Xcode, go Debug > Attach to Process... and select the iPhone app under "Likely Targets".
Start by running the iPhone app, which will mean you are already attached to that process. In the Apple Watch simulator, run the Watch app. You'll then be able to debug the iPhone side of the communication.
To debug in Watch-OS while running iPhone app and vice versa in Xcode-8.1. Required running Process need to be attached .
Visually:-

Unit Test HKSampleQuery in Swift

When I need to read data from HealthKit this is how my code looks like:
let stepsCount = HKQuantityType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
let stepsSampleQuery = HKSampleQuery(sampleType: stepsCount,
predicate: nil,
limit: 100,
sortDescriptors: nil)
{ [unowned self] (query, results, error) in
if let results = results as? [HKQuantitySample] {
self.steps = results
// Update some UI
}
self.activityIndicator.stopAnimating()
}
healthStore?.executeQuery(stepsSampleQuery)
This specific code was extracted from here for demo purpose.
So my question is:
How can I unit test this kind of code ?
I encapsulate this code in a function in a model class that knows nothing about the UI. It works like this:
At the place the you have your
// Update some UI
call a completion closure, that was passed to the function using a parameter.
You call this function from your controller class like this
hkModel.selectSteps() {
[unowned self] (query, results, error) in
// update UI
}
This way you have a clean separation between your query logic in the model class and your UIController code.
Now you can easily write a unit test calling the same method:
func testSteps() {
hkModel.selectSteps() {
[unowned self] (query, results, error) in
// XCTAssert(...)
}
}
The last thing you need is to respect that your test code is called asynchronously:
let stepExpectationEnd = expectationWithDescription("step Query")
hkModel.selectSteps() {
[unowned self] (query, results, error) in
// XCTAssert(...)
stepExpectationEnd.fulfill()
}
waitForExpectationsWithTimeout(10.0) {
(error: NSError?) in
if let error = error {
XCTFail(error.localizedDescription)
}
}
update
Because you asked:
I handle authorization at the test setup. looks like this:
var healthData: HealthDataManager?
override func setUp() {
super.setUp()
healthData = HealthDataManager()
XCTAssert(healthData != nil, "healthDadta must be there")
let authorizationAndAScheduleExpectation = expectationWithDescription("Wait for authorizatiion. Might be manual the first time")
healthData?.authorizeHealthKit({ (success: Bool, error: NSError?) -> Void in
print ("success: \(success) error \(error?.localizedDescription)")
// fails on iPad
XCTAssert(success, "authorization error \(error?.localizedDescription)")
self.healthData?.scheduleAll() {
(success:Bool, error:ErrorType?) -> Void in
XCTAssert(success, "scheduleAll error \(error)")
authorizationAndAScheduleExpectation.fulfill()
}
})
waitForExpectationsWithTimeout(60.0) {
error in
if let error = error {
XCTFail(error.localizedDescription)
}
}
}
The first time you run this code in a simulator, you have to approve authorization manually.
After the first run the tests run without manual intervention.