Whats new in Android

Lecture at University of malta as part of DevFest Malta

1. WHAT’S HOT IN GDG Malta Danny Preussler @PreusslerBerlin
2. WHO’S THAT GERMAN?
3. WHAT’S A DEVELOPER EXPERT?
4. WHAT’S A DEVELOPER EXPERT?
5. 2009 ANDROID
6. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
7. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
8. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
9. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
10. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
11. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
12. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava ViewModel View
13. DATA BINDING
14. SOOO 2016 • Material Design • Firebase • ConstraintLayout • Databinding • RxJava
15. RXJAVA tasksRepository.getTasks() .flatMap(Flowable::fromIterable) .filter(task -> { switch (currentFiltering) { case ACTIVE_TASKS: return task.isActive(); case COMPLETED_TASKS: return task.isCompleted(); case ALL_TASKS: default return true; } }) * https://github.com/googlesamples/android-architecture
16. WHAT WAS NEW IN 2017
17. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
18. • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
19. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
20. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
21. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
22. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes • Instant Apps
23. BACKGROUND CHANGES • Doze and JobScheduler started with M (Android 6) • New background limitations
24. NEW FEATURE IN ANDROID 8 • Picture in Picture • Resizable TextView • Fonts in xml and Downloadable fonts • Notification changes • Background changes •Instant apps
25. INSTANT APPS • “say no to app downloads” • (partial) app starts directly from website • Split up your app into feature modules
26. NEWS IN ARCHITECTURE • Architecture blueprints • Architecture guidelines • Architecture components
27. NEWS IN ARCHITECTURE •Architecture blueprints github.com/googlesamples/android-architecture • Architecture guidelines • Architecture components
28. NEWS IN ARCHITECTURE • Architecture blueprints •Architecture guidelines developer.android.com/topic/libraries/architecture/guide.html • Architecture components
29. NEWS IN ARCHITECTURE • Architecture blueprints •Architecture guidelines • Architecture components
31. NEWS IN ARCHITECTURE • Architecture blueprints • Architecture guidelines •Architecture components developer.android.com/topic/libraries/architecture/index.html
32. ARCHITECTURE COMPONENTS • Viewmodel • LiveData • LifeCycleObserver • Room • Pagination
33. VIEWMODEL • provides the data for a specific UI • fits great into MVVM • survives configuration change
34. VIEWMODEL • provides the data for a specific UI • fits great into MVVM • survives configuration change
35. VIEWMODEL • provides the data for a specific UI • fits great into MVVM • survives configuration change Model ViewModel View
36. VIEWMODEL • provides the data for a specific UI • fits great into MVVM • survives configuration change
37. VIEWMODEL public void onCreate(...) { model = ViewModelProviders .of(this) .get(MyViewModel.class); } class MyViewModel extends ViewModel { …
38. VIEWMODEL LIVES LONGER! Activity Activity ViewModel
39. INTRODUCING LIVE DATA Activity Activity LiveData LiveData ViewModel
40. LIVE DATA • Observable similar to RxJava • Life cycle aware • Doesn’t emit when not needed • Memory leak save
41. LIVE DATA • Observable similar to RxJava • Life cycle aware • Doesn’t emit when not needed • Memory leak save
42. LIVE DATA • Observable similar to RxJava • Life cycle aware • Doesn’t emit when not needed • Memory leak save
43. LIVE DATA • Observable similar to RxJava • Life cycle aware • Doesn’t emit when not needed • Memory leak save
44. LIVE DATA • Observable similar to RxJava • Life cycle aware • Doesn’t emit when not needed • Memory leak save
45. LIVE DATA class MyViewModel extends ViewModel { MutableLiveData<String> message = new MutableLiveData<String>(); myModel.message.observe(this, new Observer<String>() { @Override public void onChanged(String newValue) {..} }
46. LIFECYCLEOBSERVER • Helps building your own life cycle aware components • Watch Activity, Fragment or Application life cycle • Avoid memory leaks • Avoid forwarding events from activities/fragments • Introduces ProcessLifeCycle!
47. ROOM • SQLite Object Mapper • Compile time check • Works with RxJava
48. ROOM @Dao abstract class ConferenceStore { @Insert abstract void insert(List<Session> sessions); @Query("SELECT * FROM tracks") abstract List<Track> allTracks(); ... https://commonsware.com/presos/2017-11-Room
49. ROOM @Entity(tableName = "tracks") class Track { @PrimaryKey(autoGenerate = true) final Long id; @NonNull final String title; @NonNull final String location; ... https://commonsware.com/presos/2017-11-Room
50. ROOM @Database(version=1, entities = {Track.class, Session.class}) abstract public class ConferenceDatabase extends RoomDatabase { https://commonsware.com/presos/2017-11-Room
51. A NEW PROGRAMMING LANGUAGE * Java still fully supported on Android
52. KOTLIN • Modern language • Reduce boilerplate • null safe • New possibilies • Communication with swift devs • Works great with Java • Multiplatform with web and backend
53. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilies • Communication with swift devs • Multiplatform with web and backend
54. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilies • Communication with swift devs • Multiplatform with web and backend
55. fun isEligibleToVote(): Boolean { return age >= 18 }
56. fun isEligibleToVote = age >= 18
57. data class MyModel(val lastName: String, val name: String = “”)
58. ... Map<TYPE, Integer> signalStrength = new HashMap<>(); signalStrength.put(EDGE, 80); signalStrength.put(WIFI to 90); ...
59. ... val signalStrength = hashMapOf(EDGE to 80, WIFI to 90) ...
60. class MyViewModel extends ViewModel { MutableLiveData<String> message = new MutableLiveData<String>(); myModel.message.observe(this, new Observer<String>() { @Override public void onChanged(String newName) {..} }
61. class MyViewModel(): ViewModel(){ val message = MutableLiveData<String>() myModel.message.observe(this, Observer{ .. })}
62. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilies • Communication with swift devs • Multiplatform with web and backend
63. NULL SAFETY var canNeverBeNull: String var canBeNull: String?
64. if (subscription != null) { subscription.dispose() }
65. subscription?.dispose()
66. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilities • Communication with swift devs • Multiplatform with web and backend
67. val typeOfPerson = when(age){ 0 -> "New born" in 1..12 -> "Child" in 13..19 -> "Teenager" else -> "Adult" }
68. fun String.toAspectRatio(): AspectRatio? = when (this) { "1:1" -> ONE_BY_ONE "2:3" -> TWO_BY_THREE else -> null }
69. fun Int.clamp(lower: Int, upper: Int) = Math.max(lower, Math.min(this, upper)) progress.clamp(0, 100)
70. greeting shouldEqual "hello"
71. greeting.shouldEqual("hello”)
72. greeting shouldEqual "hello"
73. greeting `should equal` "hello"
74. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilities • Communication with swift devs • Multiplatform with web and backend
75. KOTLIN • Modern language • Works great with Java • Reduce boilerplate • null safe • New possibilities • Communication with swift devs • Multiplatform with web and backend support for JVM, JS, native
76. KOTLIN = fun
78. SUMMARIZE It was never so easy to start with Android
79. WRITE ANDROID IN
80. ANDROID IS MORE THAN PHONE
82. WHAT’S HOT IN GDG Malta Danny Preussler @PreusslerBerlin