This is a quick summary of interesting talk I visited during Droidcon Online 2020. This year the conference was different - due to covid-19. Nevertheless there were some thing worth mentioning!

1. OCTOBER 19, 2020
Quick conference summary
Droidcon 2020
Bartosz Kosarzycki
@bkosarzycki

2. #SECU #LANG
#JETPACK
@bkosarzycki
#UI
#BACKEND #LIBRARY
#OTHER #SDK

3. @bkosarzycki
KOTLIN
JETPACK
Flutter
PRs / Digital Nomad / Developer life etc.
reactive
programming /
coroutines
Security
Compose
Word cloud – Droidcon 2020

4. #JETPACK
Jetpack navigation
- what benefits jetpack
navigation gives us for multi-
module projects
Tahsin Dane
Ahmet Safa Orhan
@bkosarzycki

5. Jetpack navigation – dynamic feature navigation
https://developer.android.com/guide/navig
ation/navigation-dynamic
https://medium.com/google-developer-
experts/exploring-dynamic-feature-
navigation-on-android-c803bdbbca9b
- uses Android App Bundles
- reduces initial download size of the app
- "Play feature Delivery" (link) - download feature modules
on demand
@bkosarzycki

6. SplitInstallRequest
.newBuilder()
.addModule("pictureMessages")
.build()
splitInstallManager
.startInstall(request)
.addOnSuccessListener { sessionId -> ... }
.addOnFailureListener { exception -> ... }
splitInstallManager
.deferredInstall(listOf("promotionalFilters"))
Jetpack navigation – dynamic feature navigation
@bkosarzycki

7. - translates INT resource ids into human-readable
@bkosarzycki

8. http://goo.gle/compose-samples
https://developer.android.com/jetpack/compose/testing
#JETPACK
Jetpack compose – samples & testing
@bkosarzycki

9. @bkosarzycki
#UI

10. #BACKEND @bkosarzycki
KTOR - async microservices, web-applications

11. #BACKEND @bkosarzycki

12. #BACKEND @bkosarzycki

13. #BACKEND @bkosarzycki

14. #BACKEND @bkosarzycki

15. @bkosarzycki#LIBRARY
Dagger Hilt

16. @bkosarzycki#LIBRARY
Dagger Hilt – Service locator vs Dependency injection

17. @bkosarzycki#LIBRARY
Dagger Hilt

18. @bkosarzycki#LIBRARY

19. @bkosarzycki#LIBRARY
Dagger Hilt

20. Code review - Goce Anastasovski
#OTHER @bkosarzycki

21. Droidcon Keynote – modern Android / Romain Guy, Chet Haase
#OTHER @bkosarzycki

22. Keynote – modern Android / Romain Guy Chet Haase
#OTHER @bkosarzycki

23. Keynote – modern Android / Romain Guy Chet Haase
#OTHER @bkosarzycki

24. Keynote – modern Android / Romain Guy Chet Haase
#OTHER @bkosarzycki

25. CameraX
#OTHER @bkosarzycki

26. Flipper – Maksim Turaev
#OTHER @bkosarzycki

27. Kotlin multiplatfom – real world examples & performance analysis
@bkosarzycki#LANG
- ups & downs of
kotlin-multiplatform
development

28. Kotlin multiplatfom – real world examples & performance analysis
@bkosarzycki#LANG

29. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY
-
blog: kotlinx-coroutines-rx2 - when migrating from rxjava (project refactoring)
- when you want to use Kotlin coroutines in Java
(cannot [yet] be used directly)

30. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY

31. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY

32. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY

33. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY

34. Kotlin coroutines – transition & interoperability with rxjava
@bkosarzycki#LIBRARY
Structured concurrency is a programming paradigm aimed at improving the clarity, quality,
and development time of a computer program by using a structured approach
to concurrent programming. The core concept is the encapsulation of concurrent threads of
execution (here encompassing kernel and userland threads and processes) by way of
control flow constructs that have clear entry and exit points and that ensure all spawned
threads have completed before exit. The concept is analogous to structured programming,
which introduced control flow constructs that encapsulated sequential statements and
subroutines. Such encapsulation allows errors in concurrent threads to be propagated to
the control structure's parent scope and managed by the native error handling mechanisms
of each particular computer language. It allows control flow to remain readily evident by
the structure of the source code despite the presence of concurrency. To be effective, this
model must be applied consistently throughout all levels of the program-- otherwise
concurrent threads may leak out, become orphaned, or fail to have runtime errors correctly
propagated.

35. Android App Bundles – required for new apps on Google Play
#SDK @bkosarzycki

36. Android App Bundles – required for new apps on Google Play
#SDK @bkosarzycki

37. Android App Bundles – required for new apps on Google Play
#SDK @bkosarzycki

38. Google Compose – examples from Chris Banes
#JETPACK @bkosarzycki

39. Coroutine exception handling
@bkosarzycki#LANG

40. Coroutine exception handling
@bkosarzycki#LANG

41. Coroutine exception handling
@bkosarzycki#LANG

42. Coroutine exception handling
@bkosarzycki#LANG

43. Coroutine exception handling
@bkosarzycki#LANG

44. Coroutine exception handling
@bkosarzycki#LANG

45. Coroutine exception handling
@bkosarzycki#LANG

46. Coroutine exception handling
@bkosarzycki#LANG

47. Coroutine exception handling
@bkosarzycki#LANG

48. Coroutine exception handling
@bkosarzycki#LANG

49. Coroutine exception handling
@bkosarzycki#LANG

50. Coroutine exception handling
@bkosarzycki#LANG

51. https://dev.to/kpgalligan/series/3739
https://github.com/touchlab/KNConcurrencySamples
Practical Kotlin Native Concurrency Series
https://dev.to/touchlab
#LANG @bkosarzycki
Droidcon NYC in Kotlin multiplatform
- source code + live coding
LINK
Kotlin multiplatform - TOUCHLAB
- app development, workshops, trainings

52. #SECU
ASK QUESTIONS:
https://community.guardsquare.com/
@bkosarzycki
Effects of Kotlin on byte code & app security
- We've extended our open source code optimizer
ProGuard and our protection software DexGuard to
fully support Kotlin
- new open source tool to view the
Kotlin metadata hiding inside your apps

53. #SECU
ASK QUESTIONS:
https://community.guardsquare.com/
@bkosarzycki
Effects of Kotlin on byte code & app security
- example of DexGuard removing
kotlin compiler metadata for
enhanced security

54. https://android-developers.googleblog.com/2020/09/prefer-
storing-data-with-jetpack.htmlJetpack DataStore
– replaces Android SharedPrefs
- (Y) async access via coroutines Flow
- (X) no synchronous access
- has transactions
- data migration from SharedPrefs is possible
Coroutines flow
#JETPACK
Jetpack DataStore
Google DataStore CodeLab -
https://codelabs.developers.google.com/codelabs/android-
preferences-datastore/#0
https://youtu.be/lKOsI4gh9Z8?t=44
@bkosarzycki

55. #JETPACK @bkosarzycki

56. #LANG
https://www.youtube.com/watch?v=FRCASfAMXoQ
- Google is full-in Kotlin for Android
- docs & trainings are in preparation
- 70% of pro-devs use Kotlin on Android
Kotlin 1.4 Live Online event – October 12-15, 2020
@bkosarzycki

57. #LANG @bkosarzycki

58. #LANG @bkosarzycki

59. THANK
YOU Bartosz Kosarzycki
@bkosarzycki
bartosz.kosarzycki@vimncontractor.com
https://twitter.com/bkosarzycki