# šŸ“š Official Books **URL:** https://forums.kodeco.com/c/books/6.md?page=58 [Latest](https://forums.kodeco.com/latest.md) Ā· [Categories](https://forums.kodeco.com/categories.md) Ā· [Tags](https://forums.kodeco.com/tags.md) **Page:** 59 --- ## [Challenge Solutions?](https://forums.kodeco.com/t/challenge-solutions/31442)
**Author:** [@perlguy](https://forums.kodeco.com/u/perlguy)\ **Replies:** 9\ **Last updated:** [December 12, 2020, 4:48pm UTC](https://forums.kodeco.com/t/challenge-solutions/31442 "2020-12-12T16:48:37Z")
I am currently on Chapter 7 and hit the ā€œWhere to go from here?ā€ challenges, but need some help or hints. Can someone post hints and solutions to the challenges that are at the end of the chapters? Thanks! --- ## [Chapter 11, Challenge 1: How to test showAlert](https://forums.kodeco.com/t/chapter-11-challenge-1-how-to-test-showalert/126626)
**Author:** [@hettiger](https://forums.kodeco.com/u/hettiger)\ **Replies:** 1\ **Last updated:** [December 12, 2020, 2:37pm UTC](https://forums.kodeco.com/t/chapter-11-challenge-1-how-to-test-showalert/126626 "2020-12-12T14:37:35Z")
The provided solution does not test the error handling of the CalendarViewController. Itā€™s kinda misleading that this part was skipped without mentioning that in the book. Of course, I can understand, if this is somethā€¦ --- ## [Chapter 18: Build error](https://forums.kodeco.com/t/chapter-18-build-error/127367)
**Author:** [@dzungvusj](https://forums.kodeco.com/u/dzungvusj)\ **Replies:** 1\ **Last updated:** [December 12, 2020, 10:05am UTC](https://forums.kodeco.com/t/chapter-18-build-error/127367 "2020-12-12T10:05:15Z")
Vapor 4 & Swift version 5.3.1 & Mac OS bBig Sur 11.0.1. File configure.swift error message: cannot convert value of type ā€˜DatabaseIdentifier\ā€™ to expected argument type ā€˜DatabaseIdentifier\ā€™ ā€¦ --- ## [Rendering CGAL::Triangulation\_3](https://forums.kodeco.com/t/rendering-cgal-triangulation-3/127305)
**Author:** [@quaternionboy](https://forums.kodeco.com/u/quaternionboy)\ **Replies:** 2\ **Last updated:** [December 11, 2020, 11:42am UTC](https://forums.kodeco.com/t/rendering-cgal-triangulation-3/127305 "2020-12-11T11:42:51Z")
Hi there! :grin: How I would have to proceed to render a Delaunay 3D triangulation ? Iā€™m getting glitches in the edgesā€¦ and its normal given that there are four facets colliding there, so four values of normals around tā€¦ --- ## [Android studio 4 (instead of 3)](https://forums.kodeco.com/t/android-studio-4-instead-of-3/125430)
**Author:** [@hanct](https://forums.kodeco.com/u/hanct)\ **Replies:** 1\ **Last updated:** [December 10, 2020, 7:24pm UTC](https://forums.kodeco.com/t/android-studio-4-instead-of-3/125430 "2020-12-10T19:24:30Z")
Hi, I see the latest edition discusses using android studio 3. Any plan to bring in latest version of android studio 4? --- ## [Chapter 1: Using Finder in GitHub](https://forums.kodeco.com/t/chapter-1-using-finder-in-github/127149)
**Author:** [@billcod](https://forums.kodeco.com/u/billcod)\ **Replies:** 2\ **Last updated:** [December 10, 2020, 4:56pm UTC](https://forums.kodeco.com/t/chapter-1-using-finder-in-github/127149 "2020-12-10T16:56:57Z")
In Chapter 1, Pg 22, under Adding custom assets, it says: ā€œUsing Finder, locate starter/resources/TinyToyTank/TinyToyTank,rcprojectā€ In past RW Books, when I ā€œdownloaded materialsā€, I would put them in Finder, but theā€¦ --- ## [Bookmark and note icons missing](https://forums.kodeco.com/t/bookmark-and-note-icons-missing/125840)
**Author:** [@jmcelhatton](https://forums.kodeco.com/u/jmcelhatton)\ **Replies:** 8\ **Last updated:** [December 9, 2020, 5:52pm UTC](https://forums.kodeco.com/t/bookmark-and-note-icons-missing/125840 "2020-12-09T17:52:02Z")
Do not see the icons on the reader. Want to bookmark paragraphs and take notes. --- ## [LinkedList conformance for Collection](https://forums.kodeco.com/t/linkedlist-conformance-for-collection/126911)
**Author:** [@hector818](https://forums.kodeco.com/u/hector818)\ **Replies:** 0\ **Last updated:** [December 8, 2020, 6:19am UTC](https://forums.kodeco.com/t/linkedlist-conformance-for-collection/126911 "2020-12-08T06:19:00Z")
extension LinkedList: Collection { public struct Index: Comparable { public var node: Node\? static public func ==(lhs: Index, rhs: Index) -\> Bool { switch (lhs.node, rhs.noā€¦ --- ## [Ch. 4: Playground not stopping in DispatchGroup.playground](https://forums.kodeco.com/t/ch-4-playground-not-stopping-in-dispatchgroup-playground/123413)
**Author:** [@jcabrera](https://forums.kodeco.com/u/jcabrera)\ **Replies:** 1\ **Last updated:** [December 6, 2020, 11:55pm UTC](https://forums.kodeco.com/t/ch-4-playground-not-stopping-in-dispatchgroup-playground/123413 "2020-12-06T23:55:02Z")
It seems to me that PlaygroundPage.current.finishExecution() is not in the correct place in the code. Because our queuesā€™ work is asynchronous, finishExecution() is being called right after printing ā€œI got tired of waitiā€¦ --- ## [P175. The keyboard handling code does not handle safe area well + improvements](https://forums.kodeco.com/t/p175-the-keyboard-handling-code-does-not-handle-safe-area-well-improvements/85949)
**Author:** [@jkufver](https://forums.kodeco.com/u/jkufver)\ **Replies:** 10\ **Last updated:** [December 6, 2020, 7:11pm UTC](https://forums.kodeco.com/t/p175-the-keyboard-handling-code-does-not-handle-safe-area-well-improvements/85949 "2020-12-06T19:11:19Z")
The code for keyboard handling could be improved, I found the following issues: (bug) The padding is too large when keyboard is shown on phones with safe areas. The problem is that the keyboard height includes the safā€¦ --- ## [Errata for Core Data by Tutorials, 8th Edition](https://forums.kodeco.com/t/errata-for-core-data-by-tutorials-8th-edition/125426)
**Author:** [@mandafrederick](https://forums.kodeco.com/u/mandafrederick)\ **Replies:** 4\ **Last updated:** [December 5, 2020, 3:07am UTC](https://forums.kodeco.com/t/errata-for-core-data-by-tutorials-8th-edition/125426 "2020-12-05T03:07:21Z")
Creating this topic to catch any type-os and bugs in the 8th edition of Core Data by Tutorials. --- ## [Chapter 21 and 22 Unable to import toV3Completable()](https://forums.kodeco.com/t/chapter-21-and-22-unable-to-import-tov3completable/126528)
**Author:** [@syntaxtee](https://forums.kodeco.com/u/syntaxtee)\ **Replies:** 2\ **Last updated:** [December 4, 2020, 1:16pm UTC](https://forums.kodeco.com/t/chapter-21-and-22-unable-to-import-tov3completable/126528 "2020-12-04T13:16:46Z")
Hello there, Iā€™m stucked at the last two chapter in Reactive Programming in Kotlin 2nd edition. Currently, iā€™m unable to import val taskDatabase = database ?: return taskDatabase.taskDao().inserTasks( listOf( TaskIā€¦ --- ## [Chapter 4 error](https://forums.kodeco.com/t/chapter-4-error/126510)
**Author:** [@traveler](https://forums.kodeco.com/u/traveler)\ **Replies:** 1\ **Last updated:** [December 4, 2020, 10:27am UTC](https://forums.kodeco.com/t/chapter-4-error/126510 "2020-12-04T10:27:22Z")
Iā€™ve got an error message while running playground: Fatal error: Unexpectedly found nil while unwrapping an Optional value: file N3DTransforms\_Sources/Utility.swift, line 21 There is no Utility.swift in 04-3d-transformā€¦ --- ## [Playing video within an AR scene](https://forums.kodeco.com/t/playing-video-within-an-ar-scene/126498)
**Author:** [@vinodralh](https://forums.kodeco.com/u/vinodralh)\ **Replies:** 0\ **Last updated:** [December 4, 2020, 2:17am UTC](https://forums.kodeco.com/t/playing-video-within-an-ar-scene/126498 "2020-12-04T02:17:45Z")
Hi, Is there an easy way of playing videos that are in youtube or other sites within a frame using a click on behaviour? I couldnā€™t find anything on internet to show how I could do that. Thanks! --- ## [Chapter 8: Site Hosting Cybertruck Download Broken](https://forums.kodeco.com/t/chapter-8-site-hosting-cybertruck-download-broken/126374)
**Author:** [@cisforcojo](https://forums.kodeco.com/u/cisforcojo)\ **Replies:** 2\ **Last updated:** [December 3, 2020, 6:54pm UTC](https://forums.kodeco.com/t/chapter-8-site-hosting-cybertruck-download-broken/126374 "2020-12-03T18:54:01Z")
The site hosting the cybertruck for the object anchorā€™s download link is returning a 404. Is there a way we can make this is little more futureproof? --- ## [Chapter 6: PHP code yields openssl\_sign() error](https://forums.kodeco.com/t/chapter-6-php-code-yields-openssl-sign-error/126311)
**Author:** [@nathaniel29651](https://forums.kodeco.com/u/nathaniel29651)\ **Replies:** 0\ **Last updated:** [December 2, 2020, 4:01am UTC](https://forums.kodeco.com/t/chapter-6-php-code-yields-openssl-sign-error/126311 "2020-12-02T04:01:07Z")
PHP 5.4 and 7.5 both give me this error on my server. openssl\_sign() expects parameter 4 to be long, string given. Current documentation for PHP says parameter 4 should be int or string. I see this issue throughout stacā€¦ --- ## [Bug in the starter code of Chapter 10](https://forums.kodeco.com/t/bug-in-the-starter-code-of-chapter-10/126272)
**Author:** [@kubilay](https://forums.kodeco.com/u/kubilay)\ **Replies:** 0\ **Last updated:** [December 1, 2020, 5:32pm UTC](https://forums.kodeco.com/t/bug-in-the-starter-code-of-chapter-10/126272 "2020-12-01T17:32:59Z")
In this chapter, we parse open and closed events from EONET API. However, even though EOEvent.closeDate is an optional in the API response, it is being forced in the EOEvent.init method. Thus, open events never get parseā€¦ --- ## [Chapter 10 use of .merge().reduce() for EOEvents](https://forums.kodeco.com/t/chapter-10-use-of-merge-reduce-for-eoevents/121043)
**Author:** [@yakume](https://forums.kodeco.com/u/yakume)\ **Replies:** 1\ **Last updated:** [December 1, 2020, 5:29pm UTC](https://forums.kodeco.com/t/chapter-10-use-of-merge-reduce-for-eoevents/121043 "2020-12-01T17:29:22Z")
Hello! I am going through chapter 10, and when doing parallel requests for Events, in the book, we are instructed to use .merge() and chaining a .reduce() like so: static func events(forLast days: Int = 360) -\> Observabā€¦ --- ## [What is difference between master git book to git apprentice,git advance book?](https://forums.kodeco.com/t/what-is-difference-between-master-git-book-to-git-apprentice-git-advance-book/122121)
**Author:** [@yangwulong1978](https://forums.kodeco.com/u/yangwulong1978)\ **Replies:** 5\ **Last updated:** [December 1, 2020, 5:12am UTC](https://forums.kodeco.com/t/what-is-difference-between-master-git-book-to-git-apprentice-git-advance-book/122121 "2020-12-01T05:12:43Z")
What is difference between master git book to git apprentice,git advance book ? Master git = git apprentice + git advance ? --- ## [SCNPhysicsContactDelegate methods not being called](https://forums.kodeco.com/t/scnphysicscontactdelegate-methods-not-being-called/19401)
**Author:** [@dls1138](https://forums.kodeco.com/u/dls1138)\ **Replies:** 2\ **Last updated:** [November 30, 2020, 9:52am UTC](https://forums.kodeco.com/t/scnphysicscontactdelegate-methods-not-being-called/19401 "2020-11-30T09:52:50Z")
Hi there. Just bought the book a few days ago- mostly because I was mainly interested in Scenekit physics. I took a dive into Chapter 10 because it covers exactly what I was hoping to learn- how to make sense of the bitmā€¦ --- ## [I cannot find book in PDF format](https://forums.kodeco.com/t/i-cannot-find-book-in-pdf-format/125886)
**Author:** [@noch](https://forums.kodeco.com/u/noch)\ **Replies:** 1\ **Last updated:** [November 29, 2020, 7:21pm UTC](https://forums.kodeco.com/t/i-cannot-find-book-in-pdf-format/125886 "2020-11-29T19:21:30Z")
I try to find anywhere. my ebook reader support only pdf format. --- ## [Book in epub or pdf format](https://forums.kodeco.com/t/book-in-epub-or-pdf-format/125662)
**Author:** [@ava\_ios\_team](https://forums.kodeco.com/u/ava_ios_team)\ **Replies:** 1\ **Last updated:** [November 29, 2020, 7:20pm UTC](https://forums.kodeco.com/t/book-in-epub-or-pdf-format/125662 "2020-11-29T19:20:46Z")
Can we expect this book in epub or pdf format. I like to make notes on my iPad. --- ## [PDF version of book](https://forums.kodeco.com/t/pdf-version-of-book/125868)
**Author:** [@jbambridge](https://forums.kodeco.com/u/jbambridge)\ **Replies:** 1\ **Last updated:** [November 29, 2020, 7:20pm UTC](https://forums.kodeco.com/t/pdf-version-of-book/125868 "2020-11-29T19:20:03Z")
Where can I find the PDF version? I only see ePub. Thx j --- ## [Errata for Combine: Asynchronous Programming with Swift 1st Edition (v1.0.3)](https://forums.kodeco.com/t/errata-for-combine-asynchronous-programming-with-swift-1st-edition-v1-0-3/98574)
**Author:** [@mandafrederick](https://forums.kodeco.com/u/mandafrederick)\ **Replies:** 25\ **Last updated:** [November 28, 2020, 11:25pm UTC](https://forums.kodeco.com/t/errata-for-combine-asynchronous-programming-with-swift-1st-edition-v1-0-3/98574 "2020-11-28T23:25:07Z")
Creating this fresh topic to catch any typos and bugs in the 1st Edition of Combine: Asynchronous Programming with Swift (v1.0.3) The old topic can be read here: Combine: Asynchronous Programming with Swift - kodeco.comā€¦ --- ## [Can't Install Brew](https://forums.kodeco.com/t/cant-install-brew/125472)
**Author:** [@randor](https://forums.kodeco.com/u/randor)\ **Replies:** 3\ **Last updated:** [November 27, 2020, 11:37pm UTC](https://forums.kodeco.com/t/cant-install-brew/125472 "2020-11-27T23:37:38Z")
I get into Chapter 6 and then am required to install two more products: Brew and Vapor. I try to install Brew and get the error message: /bin/bash: line 112: /usr/local/bin/git: Bad CPU type in executable Failed duriā€¦ --- ## [Chapter 18: Custom Publishers & Backpressure](https://forums.kodeco.com/t/chapter-18-custom-publishers-backpressure/102581)
**Author:** [@elichigo](https://forums.kodeco.com/u/elichigo)\ **Replies:** 3\ **Last updated:** [November 26, 2020, 5:19pm UTC](https://forums.kodeco.com/t/chapter-18-custom-publishers-backpressure/102581 "2020-11-26T17:19:29Z")
I couldnā€™t figure out this, in the ShareReplay Publisher(Transformer to be more precise) when I finished Iā€™ve got this output: shareReplay: receive subscription: (PassthroughSubject) shareReplay: request unlimited sā€¦ --- ## [SwiftUI by Tutorials](https://forums.kodeco.com/t/swiftui-by-tutorials/125591)
**Author:** [@jfortyork](https://forums.kodeco.com/u/jfortyork)\ **Replies:** 1\ **Last updated:** [November 26, 2020, 7:09am UTC](https://forums.kodeco.com/t/swiftui-by-tutorials/125591 "2020-11-26T07:09:25Z")
https://www.raywenderlich.com/books/swiftui-by-tutorials/v2.0 Where can I download the PDF or ePub file for the actual book itself? I can download a zip that contains all the source code, but I canā€™t find the book itselā€¦ --- ## [Core Data by Tutorials](https://forums.kodeco.com/t/core-data-by-tutorials/125592)
**Author:** [@jfortyork](https://forums.kodeco.com/u/jfortyork)\ **Replies:** 1\ **Last updated:** [November 26, 2020, 3:35am UTC](https://forums.kodeco.com/t/core-data-by-tutorials/125592 "2020-11-26T03:35:11Z")
https://www.raywenderlich.com/books/core-data-by-tutorials/v8.0 Where can I download the ePub and PDF file for the book? --- ## [Buffer Alignment in Instancing Chapter](https://forums.kodeco.com/t/buffer-alignment-in-instancing-chapter/125604)
**Author:** [@lducot2](https://forums.kodeco.com/u/lducot2)\ **Replies:** 2\ **Last updated:** [November 26, 2020, 1:23am UTC](https://forums.kodeco.com/t/buffer-alignment-in-instancing-chapter/125604 "2020-11-26T01:23:07Z")
Hello everyone - Could someone help me understand one of the concepts explained in the chapter on instancing? In the part on morphs, we initially render the rocks with an incorrect struct and see the vertices out it orā€¦ --- ## [Errata for Design Patterns by Tutorials, 3rd Edition](https://forums.kodeco.com/t/errata-for-design-patterns-by-tutorials-3rd-edition/83653)
**Author:** [@chrisrazeware](https://forums.kodeco.com/u/chrisrazeware)\ **Replies:** 4\ **Last updated:** [November 24, 2020, 8:43pm UTC](https://forums.kodeco.com/t/errata-for-design-patterns-by-tutorials-3rd-edition/83653 "2020-11-24T20:43:00Z")
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