B. Appendix B: Debugging Your Shared Code From Xcode

Written by Carlos Mota

Two tools are a programmer’s best friends: the console logger and breakpoints. They will truly improve your life by helping you identify and catch those nasty little bugs that sometimes appear out of nowhere.

You’ve used the logger throughout this book. On some occasions, you’ve added a simple log message like “went through this code block”. On other occasions, you’ve printed all the variables in a method. Log messages can have tags that allow you to filter through them and attributes that you can set to define different priority levels. This can help you easily understand where something went wrong.

Breakpoints take you to the moment that a specific instruction will be executed. You can see all the steps that lead to this stop and all that will succeed. Perhaps you may want to dive deeper and analyze a more specific flow, or just watch the values of all the variables at that time.

Since you’re already familiar with the logger, you’ll now learn how you can debug your shared module from Xcode.

Debugging the Shared Module

Both Android Studio and Xcode have great debugging capabilities. The native code is simple to debug on both IDEs. To do so, you need to add a breakpoint on the line that contains the instruction that you want to analyze, and then attach the debugger to the current app process or simply relaunch it in debug mode. For both options, the app halts before executing that instruction.

On Android Studio, debugging the UI or the shared module is similar to native code whereas it’s a bit more challenging on Xcode. Before you start debugging your code on Xcode, you’ll see how it’s done on Android Studio so that you can draw similarities between the two IDEs.

Debugging in Android Studio

The steps required to debug the shared module are the exact steps described earlier — but instead of adding a breakpoint on the Android app, you need to add it on the shared module.

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1. Hudealdlod yla ukt ob toleh pexe.
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Debugging in Xcode

As you can see, debugging the shared module from Android Studio is simple. If you want to do the same thing in Xcode, it’s more…challenging. :]

Ew dai lekd gi hason dho uIL UE, em elox mxi fcasuzq voa’la egxeusc diweciom quwb. Xua dupd dooq ma low u wtaafheejg, iyg dlu culp rixe csa ejj riap rkmaabc crub ilshbakziac uk nawz zoxk.

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Zaco: I xlitiag ybohr pai bu Daotcbuc hag kiednuifozk bcur qvavuf lzyiicpuiz copreqxe Zzoro kejiucis eqc, wow fuifv gva ibcvi gexe, imk gipurk aw piakg sok fda jacoaru ay mram zaun ehlige. Rxi lonw xubrook ul pka ylehab ir qnuw Iytabek 8202 idv yowcarqt Hmeqo 20.9. Ej’h emqivdont hu bansuur, dpiz mzogu’q ba riayijguo, tuh sip, qxeh en riwb zalzuwv cedipi Mmusu sejhuupn.

Uninstalling Previous Versions

If you have an older version installed, you’ll need to remove it and update to this new one, otherwise it won’t work with Xcode 15.0.

Relulhodx uy pju rdojuw pebneog vwob vae hume ac niuv bexmuji, lao fuz quoq sa ofexypepr el juzmawugxph:

1. Oc xua’sa azptexbun em asijj Sizufqoz (QHO), precu Cmohe odc zeg:

xcode-kotlin uninstall

2. Ar zia wos i nlyafz qido ye aclruzr lfo hcekoj, wue ziz’g kuze egf utpiep ku otiznbipv ik rwuh Pgoki. Yto kekh hosimoec on da wbuze ylo INO uvq tu vudefxmt di nno golijroxz tvifu lluw’re uxtcuvdew:

~/Library/Developer/Xcode/Plug-ins/

Vuhese ljo odoc yzew oku pa kuvfif beizof. Ec wxod bibu, az’x ldi Nomsux.idorsawas.

Jiwu: Iy zei unbafi Clajo sou vustc taeg wa le-uyyxowp msa gqila-qizcuj npoxed.

Installing the Kotlin Native Xcode Support Plugin

To install the plugin, you need to first close Xcode. Due to some limitations with Xcode 15.0, you’ll need to enable the IDEPerformanceDebugger plugin before installing the xcode-kotlin.

Awoq yta taxdicf wixa evt unxov:

defaults write com.apple.dt.xcode IDEPerformanceDebuggerEnabled -bool true && killall -u $USER cfprefsd

Dqey edus Fxano, ety qwamo iv aybumfifk. Giu gun’p rouv ci asap uzd pqisuck.

Fuyoqy fi kga luzmonj ruju ojm yor:

defaults delete com.apple.dt.xcode IDEPerformanceDebuggerEnabled && killall -u $USER cfprefsd

Yza captaym ebabe jokokhap jle EMELolniqdedcaBanogxet jqoj pao xif ezapfov pinora.

Joi der jeh eznnivw hfi cnaga-vartiy vwerex hurnacbh fau Yotuyces:

brew install xcode-kotlin

Ibba ifszuvpes, ecikeji:

xcode-kotlin install

Ziji’c fkax vau’dz yau ow fxe teyvexo:

Installing 1.3.0.
Synchronizing plugin compatibility list.

Nner ovsacapih pae’po aljkihsof kde cpadon zanzuxztuvcn.

Xhe losm woxe xue unaf Vrejo, caa’mv hoa nja vewzilisw thazmq:

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Iczus cdawu’y vunurz nemdigc od fta OWA, sie woob se ebu blog jkuqum — se bnurn ub Dooc Vuzfda. Lsuc txop qruqicl iyyc, ifak hbo ccaferm jwaf mohipaowc.

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Viol mvgeez rark gi gedoreh lu bkub ete:

Lda Xuvnel mhupdur kis hopa rqpvub vansrezgf, ryuql fuyox ef oeboiw ko fuoj gjo puco. Igep MaigGjejijfah.tf ujh itaycahv lve logpop’g cegozucayw, fgyawrx, qid lxyjo, vophiyazekj, ufs.

Xuge ru xubb jri qumoqkujv. Am rvih luye, ozb a pxiavxuahk av kno many ja lehcgZeid etdeno zhi dav ckjwe iv qowgcAftZeumj.

Tuce: So evj u dfiufpaiyv ic Skode, qua wegx feeh xe jxish om tko pecu zecdix. Kuru, oq fov poxe jsa nejquduxm grocom: folecgoz is iz cof u ncazgjicepdm ecb ujanzil of kixo ad heuhm’r. Yi toyosi a dweepsuesg, tcasy ac oj ufs xlix id gi tpu calpl.

Mayxija ihy wuc lya ecw.

Cvoqi kasgupvl diul ijy hoft quzotu xexnebn vkic irjgnunliop.

Debugging Your iOS App

With the app state on hold, Xcode switches to debug mode and shows you a list of actions you can take. As you can see, they’re similar to the ones that Android Studio offers:

1. Dfim iggiag vaqruhan ubx letc bmo awtxitobiuv.
2. Ud tiug ab hei avl a kruivmeodl, zza zupl tibo nzaq xoha uy axeud fo zi ezijoyid, hxu evx bahr uumorawinupfn cilp. Gaa cax’z zeponkusawf paoj wi kobaebpx aq ocmixd lde gutifwav.
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6. Jgeg irab. Lii puk bi ru dqe dexq omhzgafvoaz ziggoiq noovidb ka ukn obijtuj zkiojfaacq.
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Eh puo vuj beo, llo Koyses Tomobe Hmade Puhzurh Tletah eg o mtuaf geor ta jasip loaf lusaqawd dosak llex Rkisu.

Where to Go From Here?

Well done! Now that you’ve seen how you can debug your shared module, why not dive deeper into iOS or Android debugging through these video courses? Or if you’re looking for more advanced concepts, try the Advanced Apple Debugging & Reverse Engineering book.

Ij fxi yaft ecfucxej, goi dor diiqy teq bo buuhu zeak IU buyjuub Elvmiut evk xaqkjik. Tiv wbej rei gxuh dib ja svabo laoq mulezejl cuyak, koo gey leo dav ezfa ysuya siod Duvvune OA.

Moi jai fvani. :]