# šŸ“š Official Books **URL:** https://forums.kodeco.com/c/books/6.md?page=48 [Latest](https://forums.kodeco.com/latest.md) Ā· [Categories](https://forums.kodeco.com/categories.md) Ā· [Tags](https://forums.kodeco.com/tags.md) **Page:** 49 --- ## [Race Conditions](https://forums.kodeco.com/t/race-conditions/141177)
**Author:** [@huda\_elhady](https://forums.kodeco.com/u/huda_elhady)\ **Replies:** 0\ **Last updated:** [May 30, 2021, 6:08am UTC](https://forums.kodeco.com/t/race-conditions/141177 "2021-05-30T06:08:59Z")
Iā€™m sorry Iā€™m trying to understand how this serial queue code will solve the 2 threads issue if the problem is all about that the second thread has started one clock cycle before the first thread, then I could imagineā€¦ --- ## [Errata for Flutter Apprentice, First Edition](https://forums.kodeco.com/t/errata-for-flutter-apprentice-first-edition/121572)
**Author:** [@chrisrazeware](https://forums.kodeco.com/u/chrisrazeware)\ **Replies:** 7\ **Last updated:** [May 29, 2021, 11:13am UTC](https://forums.kodeco.com/t/errata-for-flutter-apprentice-first-edition/121572 "2021-05-29T11:13:30Z")
Official errata thread for Flutter Apprentice, First Edition! --- ## [Chapter 24: Empty cookies dictionary when appleAuthCallbackHandler(\_:)](https://forums.kodeco.com/t/chapter-24-empty-cookies-dictionary-when-appleauthcallbackhandler/138545)
**Author:** [@alobaili](https://forums.kodeco.com/u/alobaili)\ **Replies:** 31\ **Last updated:** [May 29, 2021, 7:35am UTC](https://forums.kodeco.com/t/chapter-24-empty-cookies-dictionary-when-appleauthcallbackhandler/138545 "2021-05-29T07:35:19Z")
Iā€™m having trouble finding out what went wrong while following along with chapter 24 and implementing Sign In with Apple for the web. When I click the Sign In with Apple button and follow the steps, I get redirected to ā€¦ --- ## [SendGrid sevice seem not very stable](https://forums.kodeco.com/t/sendgrid-sevice-seem-not-very-stable/140201)
**Author:** [@wtj123](https://forums.kodeco.com/u/wtj123)\ **Replies:** 4\ **Last updated:** [May 28, 2021, 10:36am UTC](https://forums.kodeco.com/t/sendgrid-sevice-seem-not-very-stable/140201 "2021-05-28T10:36:57Z")
Hi there, In Chapter 25, Iā€™ve implemented all codes for sending email using SendGrid service. However, I found not every time after I fill out the email address and press the reset password button, I can get an email reā€¦ --- ## [Will be available SwiftUI Book?](https://forums.kodeco.com/t/will-be-available-swiftui-book/139481)
**Author:** [@alda-loq-369](https://forums.kodeco.com/u/alda-loq-369)\ **Replies:** 6\ **Last updated:** [May 27, 2021, 11:35pm UTC](https://forums.kodeco.com/t/will-be-available-swiftui-book/139481 "2021-05-27T23:35:06Z")
Dear community. I could see and download this book (SwiftUI by tutorials) in pdf format however it was updated and want download it in pdf format but I only see epub format. will it be available in pdf format? Best Regā€¦ --- ## [Chapter 7 (4th) RecyclerView.adapter](https://forums.kodeco.com/t/chapter-7-4th-recyclerview-adapter/141042)
**Author:** [@psb4ever](https://forums.kodeco.com/u/psb4ever)\ **Replies:** 0\ **Last updated:** [May 27, 2021, 7:34pm UTC](https://forums.kodeco.com/t/chapter-7-4th-recyclerview-adapter/141042 "2021-05-27T19:34:11Z")
Error appears class ListSelectionRecyclerViewAdapter : RecyclerView.Adapter(){ Android Studio says Type argument is not within its bounds: should be subtype of ā€˜RecyclerView.ViewHolder!ā€™ Any clue? edit: found it in ā€¦ --- ## [Android Apprentice 4th](https://forums.kodeco.com/t/android-apprentice-4th/140914)
**Author:** [@psb4ever](https://forums.kodeco.com/u/psb4ever)\ **Replies:** 1\ **Last updated:** [May 27, 2021, 7:29pm UTC](https://forums.kodeco.com/t/android-apprentice-4th/140914 "2021-05-27T19:29:58Z")
Hi what about view binding? in the first chapters i can find only findViewByID? --- ## [The free preview chapters are awesome](https://forums.kodeco.com/t/the-free-preview-chapters-are-awesome/140700)
**Author:** [@amitsrivastava](https://forums.kodeco.com/u/amitsrivastava)\ **Replies:** 1\ **Last updated:** [May 27, 2021, 5:11pm UTC](https://forums.kodeco.com/t/the-free-preview-chapters-are-awesome/140700 "2021-05-27T17:11:58Z")
I was just going through the protocol preview chapter , available for all subscribers , the way it has been explained is totally awesome, it was filling exactly the gaps that i always felt in my attempt to understand proā€¦ --- ## [TILModels Swift Package for Client & Server Models?](https://forums.kodeco.com/t/tilmodels-swift-package-for-client-server-models/140891)
**Author:** [@dleuck](https://forums.kodeco.com/u/dleuck)\ **Replies:** 2\ **Last updated:** [May 27, 2021, 2:14pm UTC](https://forums.kodeco.com/t/tilmodels-swift-package-for-client-server-models/140891 "2021-05-27T14:14:25Z")
@0xtim Can a single model (e.g. Acronym) be shared between client and server via a TILModels swift package? Obviously the attributes used to model the Fluent relationships wouldnā€™t be utilized by the client, but canā€™t thā€¦ --- ## [Observer Pattern Unit testing](https://forums.kodeco.com/t/observer-pattern-unit-testing/141009)
**Author:** [@madhurjain](https://forums.kodeco.com/u/madhurjain)\ **Replies:** 1\ **Last updated:** [May 27, 2021, 12:29pm UTC](https://forums.kodeco.com/t/observer-pattern-unit-testing/141009 "2021-05-27T12:29:55Z")
I have implemented an Observer pattern to observe the changes in the view controller. So it has one list of objects when I am updating the list count should increase by one it is increasing in the actual code but when iā€¦ --- ## [Select2 + multipart/form-data issue](https://forums.kodeco.com/t/select2-multipart-form-data-issue/140162)
**Author:** [@spock](https://forums.kodeco.com/u/spock)\ **Replies:** 1\ **Last updated:** [May 27, 2021, 8:35am UTC](https://forums.kodeco.com/t/select2-multipart-form-data-issue/140162 "2021-05-27T08:35:37Z")
Hello everyone. I use select2 in my form as it described in the Chapter 17 and it works perfect until I add enctype=ā€œmultipart/form-dataā€ parameter to the form. After that select2 just sends nil to the server (at least ā€¦ --- ## [Combine: flatMap not allowing to change object value](https://forums.kodeco.com/t/combine-flatmap-not-allowing-to-change-object-value/140958)
**Author:** [@ankit\_tlp](https://forums.kodeco.com/u/ankit_tlp)\ **Replies:** 0\ **Last updated:** [May 26, 2021, 9:09pm UTC](https://forums.kodeco.com/t/combine-flatmap-not-allowing-to-change-object-value/140958 "2021-05-26T21:09:49Z")
This is Combine publisher stream that i am creating to get input from text and making web api request. But the problem i am facing is changing the request objectā€™s properties (any mutable property in request object). Beā€¦ --- ## [Facebook authentication - solved](https://forums.kodeco.com/t/facebook-authentication-solved/140954)
**Author:** [@oleg.dr](https://forums.kodeco.com/u/oleg.dr)\ **Replies:** 0\ **Last updated:** [May 26, 2021, 8:02pm UTC](https://forums.kodeco.com/t/facebook-authentication-solved/140954 "2021-05-26T20:02:46Z")
Facebook returns email address with ā€˜\\u0040ā€™ Unicode symbol instead of ā€˜\\u{0040}ā€™ or ā€˜@ā€™, it causes an exception during the decoding. So there is the workaround: ā€¦ guard let body = response.body else { throw Abort(.inā€¦ --- ## [Ch.18 "Cannot find type 'BasicAccount' in scope"](https://forums.kodeco.com/t/ch-18-cannot-find-type-basicaccount-in-scope/136813)
**Author:** [@jasper8777](https://forums.kodeco.com/u/jasper8777)\ **Replies:** 1\ **Last updated:** [May 23, 2021, 2:57pm UTC](https://forums.kodeco.com/t/ch-18-cannot-find-type-basicaccount-in-scope/136813 "2021-05-23T14:57:34Z")
Hi all, in this chapter, when I organized the code from playground to separate files, Xcode kept showing me this error saying it cannot find BasicAccount in scope, while the BasicAccount class and the Account protocol hā€¦ --- ## ["Maps directly to actual computer hardware" - how would I know?](https://forums.kodeco.com/t/maps-directly-to-actual-computer-hardware-how-would-i-know/140511)
**Author:** [@lganti](https://forums.kodeco.com/u/lganti)\ **Replies:** 4\ **Last updated:** [May 22, 2021, 1:35pm UTC](https://forums.kodeco.com/t/maps-directly-to-actual-computer-hardware-how-would-i-know/140511 "2021-05-22T13:35:25Z")
example("imperative, early-exit") { var total = 0 for value in numbers { guard value \>= 0 else { break } total += value } print(total) } ā€œIt also maps directly to actual computer hardware so the optimizā€¦ --- ## [Flutter version 2.0](https://forums.kodeco.com/t/flutter-version-2-0/138622)
**Author:** [@dharianzi](https://forums.kodeco.com/u/dharianzi)\ **Replies:** 5\ **Last updated:** [May 22, 2021, 5:28am UTC](https://forums.kodeco.com/t/flutter-version-2-0/138622 "2021-05-22T05:28:31Z")
Will this book be updated to Flutter 2.0? --- ## [When are you updating this incomplete book?](https://forums.kodeco.com/t/when-are-you-updating-this-incomplete-book/140531)
**Author:** [@chazmanian](https://forums.kodeco.com/u/chazmanian)\ **Replies:** 2\ **Last updated:** [May 20, 2021, 7:52pm UTC](https://forums.kodeco.com/t/when-are-you-updating-this-incomplete-book/140531 "2021-05-20T19:52:07Z")
I purchased Flutter Apprentice sometime ago and there has been no update or additional content since. The book is woefully incomplete. Any idea when this book will be completed? Can I get my money back or credit towardsā€¦ --- ## [Errata for Android Test-Driven Development by Tutorials 1st Edition](https://forums.kodeco.com/t/errata-for-android-test-driven-development-by-tutorials-1st-edition/82119)
**Author:** [@mandafrederick](https://forums.kodeco.com/u/mandafrederick)\ **Replies:** 8\ **Last updated:** [May 20, 2021, 12:28am UTC](https://forums.kodeco.com/t/errata-for-android-test-driven-development-by-tutorials-1st-edition/82119 "2021-05-20T00:28:58Z")
Creating this topic to catch any typos and bugs in the 1st Edition of Android Test-Driven Development by Tutorials. --- ## [Render glitches nearly coplanar faces](https://forums.kodeco.com/t/render-glitches-nearly-coplanar-faces/139778)
**Author:** [@quaternionboy](https://forums.kodeco.com/u/quaternionboy)\ **Replies:** 2\ **Last updated:** [May 13, 2021, 9:54am UTC](https://forums.kodeco.com/t/render-glitches-nearly-coplanar-faces/139778 "2021-05-13T09:54:45Z")
Hi there! Iā€™m working with a triangulation geometry and Iā€™m getting some glitches where: several primitives share one edge: sort primitives in depth camera axis ? and \_.depthCompareFunction = .lessEqual two primā€¦ --- ## [SceneKit: How to constrain movement of a node to one axis locally, not the entire world](https://forums.kodeco.com/t/scenekit-how-to-constrain-movement-of-a-node-to-one-axis-locally-not-the-entire-world/140198)
**Author:** [@ahromada](https://forums.kodeco.com/u/ahromada)\ **Replies:** 0\ **Last updated:** [May 17, 2021, 4:49am UTC](https://forums.kodeco.com/t/scenekit-how-to-constrain-movement-of-a-node-to-one-axis-locally-not-the-entire-world/140198 "2021-05-17T04:49:56Z")
Itā€™s very easy to prevent movement of a node in one axis (X, Y, or Z) being moved by other forces with an SCNTransformConstraint.positionConstraint in world space as follows: let zPosition = node.position.z let strafinā€¦ --- ## [GitHub authentication logic issues](https://forums.kodeco.com/t/github-authentication-logic-issues/140013)
**Author:** [@ahmadh](https://forums.kodeco.com/u/ahmadh)\ **Replies:** 1\ **Last updated:** [May 14, 2021, 9:24pm UTC](https://forums.kodeco.com/t/github-authentication-logic-issues/140013 "2021-05-14T21:24:11Z")
This is probably obvious to everyone, but I just wanted to point out that the way GitHub authentication as implemented in chapter 23 has a couple of issues because it matches GitHub users to local users by username. Firā€¦ --- ## [Would I intentionally crash an application, really?](https://forums.kodeco.com/t/would-i-intentionally-crash-an-application-really/135762)
**Author:** [@botchedphoto](https://forums.kodeco.com/u/botchedphoto)\ **Replies:** 2\ **Last updated:** [May 13, 2021, 2:17pm UTC](https://forums.kodeco.com/t/would-i-intentionally-crash-an-application-really/135762 "2021-05-13T14:17:08Z")
I copied the paragraph below from Chapter 5. I think the use of ā€œcrashā€ there may be inappropriate. If Iā€™m flying in an airplane and something goes wrong on the way to my destination, I donā€™t want to crash it. Instead, Iā€¦ --- ## [Errata for Combine: Asynchronous Programming with Swift 2nd Edition](https://forums.kodeco.com/t/errata-for-combine-asynchronous-programming-with-swift-2nd-edition/126149)
**Author:** [@mandafrederick](https://forums.kodeco.com/u/mandafrederick)\ **Replies:** 6\ **Last updated:** [May 11, 2021, 6:49pm UTC](https://forums.kodeco.com/t/errata-for-combine-asynchronous-programming-with-swift-2nd-edition/126149 "2021-05-11T18:49:01Z")
Creating this topic to catch any typos and bugs in the 2nd Edition of Combine: Asynchronous Programming with Swift. --- ## ["swift build -c release" isn't generating an executable](https://forums.kodeco.com/t/swift-build-c-release-isnt-generating-an-executable/139251)
**Author:** [@ckbrown](https://forums.kodeco.com/u/ckbrown)\ **Replies:** 4\ **Last updated:** [May 10, 2021, 8:59am UTC](https://forums.kodeco.com/t/swift-build-c-release-isnt-generating-an-executable/139251 "2021-05-10T08:59:01Z")
Hey guys, Iā€™m having a strange problem. I am trying to upgrade my Vapor project by running ā€˜swift build -c releaseā€™ on my Ubuntu server and Iā€™m not getting a ā€˜releaseā€™ symlink in the build folder or a ā€˜Runā€™ executable iā€¦ --- ## [Operations states](https://forums.kodeco.com/t/operations-states/139671)
**Author:** [@huda\_elhady](https://forums.kodeco.com/u/huda_elhady)\ **Replies:** 2\ **Last updated:** [May 10, 2021, 8:25am UTC](https://forums.kodeco.com/t/operations-states/139671 "2021-05-10T08:25:08Z")
first Iā€™m sorry, Iā€™m new to iOS development. I have just started reading the Concurrency by Tutorial book. and I just donā€™t understand this part (in the attached image): what is the relationship between operation beinā€¦ --- ## [DropCharge causing memory leak](https://forums.kodeco.com/t/dropcharge-causing-memory-leak/13203)
**Author:** [@tom\_shen](https://forums.kodeco.com/u/tom_shen)\ **Replies:** 6\ **Last updated:** [May 10, 2021, 7:15am UTC](https://forums.kodeco.com/t/dropcharge-causing-memory-leak/13203 "2021-05-10T07:15:14Z")
I make the DropCharge game by following the book. After I finish, I go ahead and check the memory pane of the Debug Navigator, I found out that the memory is constantly going higher and higher every time, and when the gaā€¦ --- ## [Using Unity Games by Tutorials with Unity 2018.4.34f1 LTS?](https://forums.kodeco.com/t/using-unity-games-by-tutorials-with-unity-2018-4-34f1-lts/139220)
**Author:** [@crazybulldog](https://forums.kodeco.com/u/crazybulldog)\ **Replies:** 1\ **Last updated:** [May 8, 2021, 9:42pm UTC](https://forums.kodeco.com/t/using-unity-games-by-tutorials-with-unity-2018-4-34f1-lts/139220 "2021-05-08T21:42:43Z")
Hi devs, i would like to use unity 2018.1.4.34f1 LTS to follow along in the book.Is that ok ? or do i have to use exacly that version which is recommended in the README ? -Oliver --- ## [Chapter 9 Communicating Between Activities](https://forums.kodeco.com/t/chapter-9-communicating-between-activities/136776)
**Author:** [@amavrik](https://forums.kodeco.com/u/amavrik)\ **Replies:** 2\ **Last updated:** [May 8, 2021, 6:55pm UTC](https://forums.kodeco.com/t/chapter-9-communicating-between-activities/136776 "2021-05-08T18:55:24Z")
When using SDK version higher than 29 In ListDetailActivity.kt expression list = intent.getParcelableExtra(MainActivity.INTENT\_LIST\_KEY) as TaskList no longer runs because of the type mismatch. Needs to be changed ā€¦ --- ## [One project across chapters](https://forums.kodeco.com/t/one-project-across-chapters/139613)
**Author:** [@lenduya](https://forums.kodeco.com/u/lenduya)\ **Replies:** 0\ **Last updated:** [May 8, 2021, 4:44pm UTC](https://forums.kodeco.com/t/one-project-across-chapters/139613 "2021-05-08T16:44:12Z")
In my opinion, there should be one project we build upon across chapters as long as itā€™s still regarding that one app. Right now I implement whateverā€™s needed for the chapter, then go to the next chapter where the book ā€¦ --- ## [Chapter 4 inconsistency](https://forums.kodeco.com/t/chapter-4-inconsistency/139612)
**Author:** [@lenduya](https://forums.kodeco.com/u/lenduya)\ **Replies:** 0\ **Last updated:** [May 8, 2021, 4:39pm UTC](https://forums.kodeco.com/t/chapter-4-inconsistency/139612 "2021-05-08T16:39:19Z")
Iā€™m at chapter 4 and just implemented the mapToDomain(): override fun mapToDomain(apiEntity: ApiAnimal): AnimalWithDetails { return AnimalWithDetails( id = apiEntity.id ?: throw MappingException("aniā€¦ [Previous page](https://forums.kodeco.com/c/books/6.md?page=47) [Next page](https://forums.kodeco.com/c/books/6.md?page=49)