Android Architecture Components 소개와 응용

- 2017.10.21 GDG 인천 DevFest17
- 2017.08.07 Google for Mobile I/O Recap Korea
위 자리에서 발표했던 자료입니다.

Android Architecture Components 를 소개하고, 응용사례를 보여드립니다.

발표영상: https://www.youtube.com/watch?v=C--ZrT8wMo8

Transcript

1. ੉थ޹ (Drama&Company) rfrost77@gmail.com Android Architecture Components ࣗѐ৬ ਽ਊ #gdg #incheon #devfest #android
2. Activity BroadcastReceiver Service ContentProvider জ੉ যڌѱ جইоח૑ ࢸݺ೧઱૑ ঋח׮
3. We want ѐߊ੗ٜীѱ OSী ؀೧ ؊ ݆਷ о੉٘ܳ ઱੗
4. Ӓېࢲ Architecture Components
5. Architecture Components Easy handling Lifecycles Lifecycle aware observables (LiveData) Lightweight ViewModel Object mapping for SQLite (Room)
6. Architecture Components Easy handling Lifecycles Lifecycle aware observables (LiveData) Lightweight ViewModel Object mapping for SQLite (Room) Paging Library
7. Lifecycles
8. class MainActivity extends AppCompatActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, (location) -> { // update UI }); } }
9. class MainActivity extends AppCompatActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, (location) -> { // update UI }); } public void onStart() { super.onStart(); myLocationListener.start(); } public void onStop() { super.onStop(); myLocationListener.stop(); } }
10. class MainActivity extends AppCompatActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, (location) -> { // update UI }); } public void onStart() { super.onStart(); Util.checkUserStatus(result -> { if (result) { myLocationListener.start(); } }); } }
11. class MainActivity extends AppCompatActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, (location) -> { // update UI }); } public void onStart() { super.onStart(); Util.checkUserStatus(result -> { if (result) { myLocationListener.start(); } }); } } Activityо stopೠ ੉റ ܻࠛݶ যڌѱ ؼө?
12. onCreate onStart onResume Util.checkUserStatus()
13. onCreate onStart onResume onPause onStop onDestroy Util.checkUserStatus() myLocationListener.stop()
14. onCreate onStart onResume onPause onStop onDestroy Util.checkUserStatus() myLocationListener.stop() myLocationListener.start()
15. onCreate onStart onResume onPause onStop onDestroy Util.checkUserStatus() myLocationListener.stop() myLocationListener.start() -_-;;
16. LifecycleOwner ۄ੉೐ࢎ੉௿ ੗न * Activity or Fragment LifecyclesObserver ۄ੉೐ࢎ੉௿ਸ ݽפఠ݂ ೡ ࣻ ੓ח ੋఠಕ੉झ
17. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, getLifecycle(), location -> { // update UI }); Util.checkUserStatus(result -> { if (result) { myLocationListener.enable(); } }); } }
18. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, getLifecycle(), location -> { // update UI }); Util.checkUserStatus(result -> { if (result) { myLocationListener.enable(); } }); } }
19. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, getLifecycle(), location -> { // update UI }); Util.checkUserStatus(result -> { if (result) { myLocationListener.enable(); } }); } }
20. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, getLifecycle(), location -> { // update UI }); Util.checkUserStatus(result -> { if (result) { myLocationListener.enable(); } }); } }
21. class MyLocationListener { private boolean enabled = false; private Lifecycle lifecycle; public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { ... } public void enable() { enabled = true; if (lifecycle.getCurrentState().isAtLeast(STARTED)) { // connect if not connected } } }
22. class MyLocationListener { private boolean enabled = false; private Lifecycle lifecycle; public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { ... } public void enable() { enabled = true; if (lifecycle.getCurrentState().isAtLeast(STARTED)) { // connect if not connected } } }
23. class MyLocationListener implements LifecycleObserver { public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { lifecycle.addObserver(this); } @OnLifecycleEvent(Lifecycle.Event.ON_START) void start() { if (enabled) { // connect } } @OnLifecycleEvent(Lifecycle.Event.ON_STOP) void stop() { // disconnect if connected } }
24. class MyLocationListener implements LifecycleObserver { public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { lifecycle.addObserver(this); } @OnLifecycleEvent(Lifecycle.Event.ON_START) void start() { if (enabled) { // connect } } @OnLifecycleEvent(Lifecycle.Event.ON_STOP) void stop() { // disconnect if connected } }
25. class MyLocationListener implements LifecycleObserver { public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { lifecycle.addObserver(this); } @OnLifecycleEvent(Lifecycle.Event.ON_START) void start() { if (enabled) { // connect } } @OnLifecycleEvent(Lifecycle.Event.ON_STOP) void stop() { // disconnect if connected } }
26. class MyLocationListener implements LifecycleObserver { public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { lifecycle.addObserver(this); } @OnLifecycleEvent(Lifecycle.Event.ON_START) void start() { if (enabled) { // connect } } @OnLifecycleEvent(Lifecycle.Event.ON_STOP) void stop() { // disconnect if connected } }
27. class MyLocationListener implements LifecycleObserver { public MyLocationListener(Context context, Lifecycle lifecycle, Callback callback) { lifecycle.addObserver(this); } @OnLifecycleEvent(Lifecycle.Event.ON_START) void start() { if (enabled) { // connect } } @OnLifecycleEvent(Lifecycle.Event.ON_STOP) void stop() { // disconnect if connected } } झझ۽ ۄ੉೐ࢎ੉௿ਸ ೩ٜ݂
28. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { myLocationListener = new MyLocationListener(this, getLifecycle(), location -> { // update UI }); Util.checkUserStatus(result -> { if (result) { myLocationListener.enable(); } }); } } NO onStart, onStop
29. Lifecycles makes… Easy handling Lifecycles
30. LiveData
31. LiveData<T> An observable Lifecycle aware Auto subscription
32. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { LiveData<Location> myLocationListener = ...; Util.checkUserStatus(result -> { if (result) { myLocationListener.observe(this, location -> { // update UI }); } }); } }
33. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { LiveData<Location> myLocationListener = ...; Util.checkUserStatus(result -> { if (result) { myLocationListener.observe(this, location -> { // update UI }); } }); } }
34. class MainActivity extends LifecycleActivity { private MyLocationListener myLocationListener; public void onCreate(Bundle savedInstanceState) { LiveData<Location> myLocationListener = ...; Util.checkUserStatus(result -> { if (result) { myLocationListener.observe(this, location -> { // update UI }); } }); } } Lifecycle
35. class MyLocationListener extends LiveData<Location> { public MyLocationListener(Context context) { ... } @Override protected void onActive() { // connect if enabled } @Override protected void onInactive() { // disconnect if connected } }
36. class MyLocationListener extends LiveData<Location> { public MyLocationListener(Context context) { ... } @Override protected void onActive() { // connect if enabled } @Override protected void onInactive() { // disconnect if connected } } 1+ active observer 0 active observer
37. Active Observer? ۄ੉೐ࢎ੉௿੉ ୭ࣗ STARTED ژח RESUMED ী ੓ח Observer
38. class MyLocationListener extends LiveData<Location> { private LocationManager locationManager; private LocationListener listener = new LocationListener() { @Override public void onLocationChanged(Location location) { setValue(location); } }; private void connect() { locationManager.requestLocationUpdates(...); } }
39. class MyLocationListener extends LiveData<Location> { private LocationManager locationManager; private LocationListener listener = new LocationListener() { @Override public void onLocationChanged(Location location) { setValue(location); } }; private void connect() { locationManager.requestLocationUpdates(...); } } Observerীѱ ؘ੉ఠܳ ࠁմ׮
40. LiveData<T> Lifecycle aware No Activityes & Fragments * Easy Testing!!!
41. ViewModel
42. class MainActivity extends LifecycleActivity { private LiveData<User> userData; public void onCreate(Bundle savedInstanceState) { String userId = "userId@gmail.com"; userData = webservice.fetchUser(userId); userData.observe(this, user -> { // update UI }); } }
43. class MainActivity extends LifecycleActivity { private LiveData<User> userData; public void onCreate(Bundle savedInstanceState) { String userId = "userId@gmail.com"; userData = webservice.fetchUser(userId); userData.observe(this, user -> { // update UI }); } } Activityо ഥ੹ೞݶ যڌѱ غחо?
44. onCreate onStart onResume onPause onStop onDestroy web service.fetchUser() Activity Rotated onCreate onStart onResume web service.fetchUser() -_-;;
45. onCreate onStart onResume onPause onStop onDestroy web service.fetchUser() Activity Rotated onCreate onStart onResume p(^◇^)/
46. class MyActivityViewModel extends ViewModel { private LiveData<User> userData; public LiveData<User> getUser(String userId) { if (userData == null) { userData = webservice.fetchUser(userId); } return userData; } }
47. class MainActivity extends LifecycleActivity { public void onCreate(Bundle savedInstanceState) { String userId = "userId@gmail.com"; ViewModelProviders.of(this) .get(MyActivityViewModel.class) .getUser(userId) .observe(this, user -> { // update UI }); } }
48. class MainActivity extends LifecycleActivity { public void onCreate(Bundle savedInstanceState) { String userId = "userId@gmail.com"; ViewModelProviders.of(this) .get(MyActivityViewModel.class) .getUser(userId) .observe(this, user -> { // update UI }); } } ೠ Activityীࢲ ҕਬೞח ViewModelਸ ࠛ۞ৡ׮
49. class MainActivity extends LifecycleActivity { public void onCreate(Bundle savedInstanceState) { String userId = "userId@gmail.com"; ViewModelProviders.of(this) .get(MyActivityViewModel.class) .getUser(userId) .observe(this, user -> { // update UI }); } }
50. ViewModel Data holder by Activity & Fragment * Singleton by Activity UI Gateway NEVER references View & Activity & Fragment * Easy Testing!!!
51. Room (ORM of SQLite)
52. Guide to SQLite
53. Boilerplate-free Compile time verification We want…
54. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); }
55. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); } @Entity public class User { @PrimaryKey private int uid; private String firstName; private String lastName; }
56. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); } @Entity public class User { @PrimaryKey private int uid; private String firstName; private String lastName; } @Database(entities = {User.class}, version = 1) public abstract class MyDatabase extends RoomDatabase { public abstract UserDao userDao(); }
57. MyDatabase db = Room .databaseBuilder(getApplicationContext(), MyDatabase.class) .build();
58. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); }
59. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); @Insert void insertAll(User... users); }
60. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); @Insert void insertAll(User... users); @Delete void delete(User user); }
61. @Dao interface UserDao { @Query("SELECT * FROM user WHERE first_name :first AND last_name :last") User findByName(String first, String last); @Insert void insertAll(User... users); @Delete void delete(User user); @Update void updateAll(List<User> users); }
62. Room with SQL Query
63. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
64. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
65. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
66. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
67. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
68. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
69. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
70. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid); @Entity public class User { @PrimaryKey private int uid; private String firstName; private String lastName; } Same Scheme
71. @Query("SELECT uid, firstName, lastName FROM users WHERE uid :uid") User findByUid(String uid);
72. @Query("SELECT uid, firstName, lastName FROM users WHERE uid :uid") User findByUid(String uid); Compile time ERROR!
73. Room Observability
74. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") User findByUid(String uid);
75. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") LiveData<User> findByUid(String uid);
76. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") LiveData<User> findByUid(String uid); public class MyActivityViewModel extends ViewModel { private LiveData<User> userData; public MyActivityViewModel(UserDao userDao) { userData = userDao.findByUid("uid"); } }
77. @Query("SELECT uid, firstName, lastName FROM user WHERE uid :uid") Flowable<User> findByUid(String uid); RxJava2
78. Boilerplate-free Compile time verification Observable Room gives…
79. Paging Library (Best with Room)
80. Page1 Page2 Page3
81. We need… Twist query data for pagination Query by page Check item diff
82. We need… Twist query data for pagination Query by page Check item diff Paging Library!
83. PagedList Adapter PagedList DataSource
84. DataSource Handle incremental data loading Load queryо ৈӝী ੓׮.
85. Loaded automatically from a DataSource on a background thread PagedList Data page size prefetch distance Configure LiveData<PagedList> LivePageListProvider
86. ઺ࠂਵ۽ оઉয়ח чਸ ୓௼ೠ׮. PagedList Adapter
87. @Query("SELECT * FROM user ORDER BY lastName ASC") LivePagedListProvider<Integer, User> usersByLastName(); Builder of LiveData<PagedList>
88. public class MyActivityViewModel extends ViewModel {
 public final LiveData<PagedList<User>> usersList; public MyActivityViewModel(UserDao userDao) { usersList = userDao.usersByLastName().create( /* initial load position */ 0, new PagedList.Config.Builder() .setPageSize(50) .setPrefetchDistance(50) .build()); } }
89. class MainActivity extends AppCompatActivity {
 public void onCreate(Bundle savedInstanceState) { MyActivityViewModel viewModel = ViewModelProviders.of(this) .get(MyActivityViewModel.class); RecyclerView recyclerView = findViewById(R.id.user_list); UserAdapter adapter = new UserAdapter(); viewModel.usersList.observe(this, pagedList -> adapter.setList(pagedList)); recyclerView.setAdapter(adapter); } }

90. public class UserAdapter extends PagedListAdapter<User, RecyclerView.ViewHolder> { public UserAdapter() { super(DIFF_CALLBACK); } public static final DiffCallback<User> DIFF_CALLBACK = new DiffCallback<User>() { @Override public boolean areItemsTheSame(@NonNull User oldUser, @NonNull User newUser) { return oldUser.getId() == newUser.getId(); } @Override public boolean areContentsTheSame(@NonNull User oldUser, @NonNull User newUser) { // Incorrectly returning false here will result in too many animations. return oldUser.equals(newUser); } } }
91. public class UserAdapter extends PagedListAdapter<User, RecyclerView.ViewHolder> { public UserAdapter() { super(DIFF_CALLBACK); } public static final DiffCallback<User> DIFF_CALLBACK = new DiffCallback<User>() { @Override public boolean areItemsTheSame(@NonNull User oldUser, @NonNull User newUser) { return oldUser.getId() == newUser.getId(); } @Override public boolean areContentsTheSame(@NonNull User oldUser, @NonNull User newUser) { // Incorrectly returning false here will result in too many animations. return oldUser.equals(newUser); } } }
93. Paging Library Do not need to twist query data for pagination Do not need to query by page Do not need to check diff
94. Architecture
95. ViewModel Repository UI Activity Fragment Data Source Room API Content Provider LiveData MVVM Paging Library
96. জ ҳઑܳ ׮द ૞ঠ ೞաਃ?
97. അ੤੄ ҳઑо ఍఍ೞ׮ݶ Do not rewrite app! ৉ೡਸ ੉೧ೞҊ জ੄ ౠࢿী ݏѱ ࢴযࢲ ഝਊೞۄ
98. ViewModel Repository Data Source Room API Content Provider UI Activity Fragment Presenter LiveData LifeCycle MVP with full AAC Paging Library
99. ViewModel Repository Data Source Room API Content Provider UI Activity Fragment Presenter LiveData LifeCycle MVP with AAC Paging Library
100. ViewModel Repository Data Source Room API Content Provider UI Activity Fragment Presenter LiveData LifeCycle Paging Library MVP with LiveData LiveData
101. ViewModel Repository Data Source Room API Content Provider UI Activity Fragment Presenter LiveData LifeCycle Paging Library Observer subscribe MVP without LiveData
102. AACח بҳ п੗ জী ݏח ҳઑܳ ਬ૑ೞݴ ੜ ഝਊೞৈ ௏٘ܳ ѐࢶ೤द׮
103. #gdg #incheon #devfest #android Thank You! ੉थ޹ (Drama&Company) rfrost77@gmail.com