Slide for Facebook Circle Dev #2 Yogyakarta

1. 15 Agustus 2017
Android Architecture Components
Facebook DevCircle Yoygakarta #2

2. ./siapasaya
Pratama Nur Wijaya
Android Developer & Kotlin Enthusiast
Co Founder @KotlinID
t.me/KotlinID
github.com/pratamawijaya
pratamwijaya.com

3. “Sebuah kisah tentang perjalanan seorang Android
Development”

4. ✤ Menulis logic kode hanya didalam activity/fragment
🍝
✤ Tidak mengenal yang namanya design pattern 🙈
✤ Hanya mengikuti/manut tutorial yang ada di web,
misal AndroidHive
✤ Selama app jalan dan client bahagia, kenapa tidak ? 🐯

5. “Semakin sering aktif diforum dan baca hal-hal yang
menarik, dan mulai mencoba hal baru”
…Perubahan…

6. ✤ Mulai mengenal pattern
✤ MVP, Singleton, Repository Pattern
✤ Clean Architecture 😎
✤ Unit Test 🎸

7. ✤ Semua itu dari community https://github.com/
googlesamples/android-architecture
✤ Belum ada standarisasi yang jelas
Masalahnya

8. Android Architecture Components
(AAC)

9. Apa itu AAC
✤ Library
✤ Guidelines
✤ Tujuan dari AAC
✤ Standarisasi
✤ Mengurangi Boilerplate
✤ Mengurangi kode yang berulang

10. Masalah yang diselesaikan oleh AAC
✤ Lifecycle
✤ Persistence & Offline support

11. Masalah yang diselesaikan oleh AAC
✤ Lifecycle
✤ LifecycleOwner + LifecycleObserver
✤ Live Data
✤ ViewModel
✤ Persistence & Offline Support
✤ Room

12. Menambahkan dependency
• compile "android.arch.lifecycle:runtime:1.0.0-alpha5"
• compile "android.arch.lifecycle:extensions:1.0.0-alpha5"
• annotationProcessor "android.arch.lifecycle:compiler:1.0.0-alpha5"

13. Android Activity Lifecycle

14. LifecycleObserver

15. Sebelum
public class MyLocationListener {
!//
public void start() {
Log.d(TAG, "start: ");
locationManager = (LocationManager) context
.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
MIN_TIME_UPDATE, MIN_DISTANCE_UPDATE, listener);
!// Force an update with the last location, if available.
Location lastLocation = locationManager.getLastKnownLocation(
LocationManager.GPS_PROVIDER);
if (lastLocation !!= null) {
listener.onLocationChanged(lastLocation);
}
}
public void stop() {
Log.d(TAG, "stop: ");
if (locationManager !!= null) {
locationManager.removeUpdates(listener);
}
}
}

16. Sebelum
public class MainActivity extends AppCompatActivity implements EasyPermissions.PermissionCallbacks, LocationListener {
@Override
protected void onStart() {
super.onStart();
requestPermissionLocation();
}
@AfterPermissionGranted(RC_LOCATION)
private void requestPermissionLocation() {
String[] perms = {Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION};
if (EasyPermissions.hasPermissions(this, perms)) {
myLocationListener.start();
} else {
EasyPermissions.requestPermissions(this, "Need permission location",
RC_LOCATION, perms);
}
}
@Override
protected void onStop() {
super.onStop();
myLocationListener.stop();
}
}

17. Sesudah
public class MyLocationListenerObserver implements LifecycleObserver {
public MyLocationListenerObserver(Context context, LifecycleOwner lifecycle, LocationListener listener) {
!// ….
!// observe to lifecycle
this.lifecycle.getLifecycle().addObserver(this);
}
@OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
void start() {
Log.d(TAG, "start: ");
locationManager = (LocationManager) context
.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_UPDATE, MIN_DISTANCE_UPDATE, mListener);
!// Force an update with the last location, if available.
Location lastLocation = locationManager.getLastKnownLocation(
LocationManager.GPS_PROVIDER);
if (lastLocation !!= null) {
mListener.onLocationChanged(lastLocation);
}
}
@OnLifecycleEvent(Lifecycle.Event.ON_PAUSE)
void stop() {
Log.d(TAG, "stop: ");
if (locationManager !!= null) {
locationManager.removeUpdates(mListener);
locationManager = null;
}
}
}

18. Sesudah
public class MainLifecyleActivity extends LifecycleActivity implements LocationListener,
EasyPermissions.PermissionCallbacks {
private static final String TAG = MainLifecyleActivity.class.getSimpleName();
private static final int RC_LOCATION = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_lifecyle);
requestPermissionLocation();
}
@AfterPermissionGranted(RC_LOCATION)
private void requestPermissionLocation() {
String[] perms = {Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION};
if (EasyPermissions.hasPermissions(this, perms)) {
new MyLocationListenerObserver(this, this, this);
} else {
EasyPermissions.requestPermissions(this, "Need permission location",
RC_LOCATION, perms);
}
}
}

19. LiveData
Digunakan untuk membungkus (encapsulate) data, dan
mengijinkan data untuk di observe, mirip seperti observable
(RxJava) tapi lebih respect dengan activity lifecycle
LiveData<User>

20. Location LiveData
public class LocationLiveData extends LiveData<Location> {
private static LocationLiveData sLocationLiveData;
@MainThread
public static LocationLiveData get(Context context) {
if (sLocationLiveData !== null) {
sLocationLiveData = new LocationLiveData(context);
}
return sLocationLiveData;
}
private LocationLiveData(Context context) {
listener = new SimpleListener();
locationManager = (LocationManager) context.getSystemService(
Context.LOCATION_SERVICE);
}
@Override
protected void onActive() {
super.onActive();
Log.d(TAG, "onActive: ");
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, listener);
}
@Override
protected void onInactive() {
super.onInactive();
Log.d(TAG, "onInactive: ");
locationManager.removeUpdates(listener);
}
}

21. Location LiveData
package com.pratamawijaya.androidlifecycleownerobserver
import android.arch.lifecycle.LifecycleActivity
import android.arch.lifecycle.Observer
import android.location.Location
import android.os.Bundle
import android.util.Log
import com.pratamawijaya.androidlifecycleownerobserver.livedata.LocationLiveData
class MainLiveDataActivity : LifecycleActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main_live_data)
LocationLiveData.get(this).observe(this,
Observer<Location> {
location !->
Log.d(TAG, "onChanged: " + location!?.latitude)
})
}
companion object {
private val TAG = MainLifecyleActivity!::class.java.simpleName
}
}

22. ViewModel
Penyelamat data saat orientasi device berubah

23. ViewModel Lifecycle

24. ViewModel
class ProMatchesViewModel : ViewModel() {
@Inject
lateinit var matchesRepo: MatchesRepository
private var liveMatchesData: LiveData<List<Matches!>>? = null
init {
BaseApp.appComponent.inject(this)
}
fun getProMatchesData(): LiveData<List<Matches!>> {
if (liveMatchesData !== null) {
liveMatchesData = MutableLiveData<List<Matches!>>()
liveMatchesData = matchesRepo.getProMatches()
}
return liveMatchesData as LiveData<List<Matches!>>
}
override fun onCleared() {
super.onCleared()
d { "vm cleared" }
}
}
https:!//github.com/pratamawijaya/DotaTournamentMatch-ArchComponentAndroid

25. ViewModel
class MainActivity : LifecycleActivity() {
private lateinit var proMatchesVM: ProMatchesViewModel
private lateinit var rvMatches: RecyclerView
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
proMatchesVM = ViewModelProviders.of(this).get(ProMatchesViewModel!::class.java)
rvMatches = findViewById(R.id.rvMatches)
rvMatches.layoutManager = LinearLayoutManager(this)
proMatchesVM.getProMatchesData().observe(this, Observer {
result !->
LastAdapter(result!!!, BR.matches)
.map<Matches>(R.layout.layout_item_matches)
.into(rvMatches)
})
}
}
https:!//github.com/pratamawijaya/DotaTournamentMatch-ArchComponentAndroid

26. Room
Sudah saatnya melupakan kepedihan ketika membuat
database dengan SQLite 😂
Abstraction layer untuk SQLite

27. Dependency
• compile "android.arch.persistence.room:runtime:1.0.0-alpha5"
• annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha5"
• compile "android.arch.persistence.room:runtime:1.0.0-alpha5"
• kapt "android.arch.persistence.room:compiler:1.0.0-alpha5"
Kotlin Version

28. Room Components
✤ Database (Komponen untuk membuat database)
✤ Entity (Komponen yang merepresentasikan database row kedalam
class)
✤ DAO (Interface yang didalamnya method untuk akses database)

29. Entity
package id.kotlin.sample.room.data
import android.arch.persistence.room.ColumnInfo
import android.arch.persistence.room.Entity
import android.arch.persistence.room.PrimaryKey
@Entity
data class User constructor(@PrimaryKey(autoGenerate = true)
@ColumnInfo(name = "user_id") val id: Long,
@ColumnInfo(name = "first_name") val firstName: String,
@ColumnInfo(name = "last_name") val lastName: String)
https:!//github.com/KotlinID/android-room-kotlin

30. DAO
package id.kotlin.sample.room.data
import android.arch.persistence.room.Dao
import android.arch.persistence.room.Delete
import android.arch.persistence.room.Insert
import android.arch.persistence.room.OnConflictStrategy
import android.arch.persistence.room.Query
import android.arch.persistence.room.Update
@Dao
interface UserDao {
@Insert(onConflict = OnConflictStrategy.REPLACE)
fun createUser(user: User)
@Query("SELECT * FROM User")
fun findAll(): List<User>
@Update
fun updateUser(user: User)
@Delete
fun deleteUser(user: User)
}
https:!//github.com/KotlinID/android-room-kotlin

31. Database
package id.kotlin.sample.room.data
import android.arch.persistence.room.Database
import android.arch.persistence.room.RoomDatabase
@Database(entities = arrayOf(User!::class), version = 1)
abstract class Database : RoomDatabase() {
abstract fun userDao(): UserDao
}
https:!//github.com/KotlinID/android-room-kotlin

32. CRUD
package id.kotlin.sample.room.main
class MainActivity : AppCompatActivity() {
private fun getUsers(): List<User> {
val dao = Room.database.userDao()
val users = dao.findAll()
if (users.isEmpty()) {
val user = User(getId(), "Budi", "Oktaviyan Suryanto")
dao.createUser(user)
return dao.findAll()
}
return users
}
}
https:!//github.com/KotlinID/android-room-kotlin

33. CRUD
package id.kotlin.sample.room.create
class AddActivity : AppCompatActivity() {
private fun addButtonListener() {
btnAdd.setOnClickListener {
val firstName = editFirstname.text.toString()
val lastName = editLastname.text.toString()
if (firstName.isNotEmpty().and(lastName.isNotEmpty())) {
async(UI) {
bg {
val dao = Room.database.userDao()
val user = User(getId(), firstName, lastName)
dao.createUser(user)
}
setResult(RESULT_OK)
finish()
}
} else {
toast(ctx.getString(R.string.message_create_user))
}
}
}
}
https:!//github.com/KotlinID/android-room-kotlin

34. CRUD
class EditActivity : AppCompatActivity() {
private fun editButtonListener() {
if (firstName.isNotEmpty().and(lastName.isNotEmpty())) {
async(UI) {
bg {
val dao = Room.database.userDao()
val user = User(data.id, firstName, lastName)
dao.updateUser(user)
}
setResult(RESULT_OK)
finish()
}
}
}
}
https:!//github.com/KotlinID/android-room-kotlin

35. Reference
✤ https://developer.android.com/topic/libraries/architecture/index.html
✤ https://blog.stylingandroid.com/architecture-components-lifecycle/
✤ https://github.com/KotlinID
✤ https://codelabs.developers.google.com/codelabs/android-lifecycles
✤ https://codelabs.developers.google.com/codelabs/android-persistence
✤ Thanks to Telegram Group @KotlinID @androidDevBdg