Architecture Components - Lifecycle library

a slide of architecture components about lifecycle library.

Transcript

1. CA.apk #3 Google I/O 2017 ใࠂձ @CyberAgent
   Masaki Ogata
   ArchitectureComponents
   Lifecycle library :)
   

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2. ࣗݾ঺հ
   Masaki Ogata
   CyberAgent, Inc. / AbemaTV, Inc.
   ogaclejapan
   @ogaclejapan
   New
   

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3. ͍ͭʹ…
   ॳ౰બ͠·ͨ͠
   
   

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4. ॳI/O ŝŦŝŦŝŦŝŦᴸᴸᴸ ƅ㱼ƅ㲇 ƅ㱼ƅ㲇ƅ㱼ƅ)㲇ƅ㱼ƅ)ᴸᴸᴸᴸ!!
   

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5. Google Keynote
   

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6. Google Keynote
   

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7. What’s new for Android TV
   

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8. Single Codebase, Two Apps with Flutter and Firebase
   

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9. Google Play Awards
   

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10. Google Play Awards
    

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13. allprojects {
    repositories {
    jcenter()
    maven { url 'https://maven.google.com' }
    }
    }
    dependencies {
    compile "android.arch.lifecycle:runtime:1.0.0-alpha1"
    compile "android.arch.lifecycle:extensions:1.0.0-alpha1"
    annotationProcessor "android.arch.lifecycle:compiler:
    1.0.0-alpha1"
    }
    1. Add the Google Maven repository
    2. Add Architecture Components - Lifecycle
    

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14. Handling Lifecycles
    

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15. ϥΠϑαΠΫϧΛ΋ͭ͜ͱΛࣔ͢ΠϯλϑΣʔε
    • LifecycleOwner
    public interface LifecycleOwner {
    Lifecycle getLifecycle();
    }
    • LifecycleRegistryOwner (※Temporary)
    public interface LifecycleRegistryOwner extends
    LifecycleOwner {
    @Override
    LifecycleRegistry getLifecycle();
    }
    

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16. ݱঢ়Ͱ͸LifecycleActivity, LifecycleFragment,
    LifecycleServiceΫϥε͕ϥΠϒϥϦ಺ʹ༻ҙ͞Ε͍ͯΔ
    public class LifecycleActivity
    extends FragmentActivity implements LifecycleRegistryOwner {
    private final LifecycleRegistry mRegistry = new
    LifecycleRegistry(this);
    @Override
    public LifecycleRegistry getLifecycle() {
    return mRegistry;
    }
    }
    ※Alpha൛ͩͱAppCompatActivity൛͸࣮૷͍ͯ͠ͳ͍
    

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17. AppCompatActivityͰLifecycleΛࢼ͍ͨ͠ਓ͸ࣗલͰ
    public class LifecycleCompatActivity
    extends AppCompatActivity implements LifecycleRegistryOwner
    {
    private final LifecycleRegistry mRegistry = new
    LifecycleRegistry(this);
    @Override
    public LifecycleRegistry getLifecycle() {
    return mRegistry;
    }
    }
    
    Ϋϥε಺ͷ࣮૷ίʔυ͸LifecycleActivityͱશ͘ಉ͡ɻ

    ͜Ε͚ͩͰࣗಈతʹϥΠϑαΠΫϧʹԠͯͪ͡ΌΜͱಈ͘
    

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18. ϥΠϑαΠΫϧΛ؍ଌ͢ΔͨΊͷΠϯλϑΣʔε
    • LifecycleObserver
    public interface LifecycleObserver {
    }
    

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19. ϥΠϑαΠΫϧΛ؍ଌ͢ΔͨΊͷΠϯλϑΣʔε
    • LifecycleObserver
    public interface LifecycleObserver {
    }
    public class FooObserver implements LifecycleObserver {
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    void start() { /* Start something. */ }
    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    void stop() { /* Stop something. */ }
    }
    

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20. ͋ͱ͸LifecycleOwnerͷLifecycleΫϥεʹadd͢Δ͚ͩ
    public class FooActivity extends LifecycleActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ...
    getLifecycle().addObserver(new FooObserver());
    }
    }
    

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21. ͋ͱ͸LifecycleOwnerͷLifecycleΫϥεʹadd͢Δ͚ͩ
    public class FooActivity extends LifecycleActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ...
    getLifecycle().addObserver(new FooObserver());
    }
    }
    FooActivity: ⇠ onStart [0ms]
    FooObserver: Start something.
    FooActivity: ⇢ onResume()
    ...
    FooActivity: ⇠ onPause [0ms]
    FooObserver: Stop something.
    FooActivity: ⇢ onStop()
    ActivityͷϥΠϑαΠΫϧʹϩά
    Λ࢓ࠐΜͰ࣮ߦͯ͠ΈΔͱ…
    

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22. “Lifecycle-aware components”
    public class FooObserver implements LifecycleObserver {
    public FooObserver(Lifecycle lifecycle) {
    ...
    this.lifecycle.addObserver(this);
    }
    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    void start() { /* Start something. */ }
    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    void stop() { /* "Stop something." */ }
    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    void cleanup() { lifecycle.removeObserver(this); }
    }
    

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23. LifecycleΫϥε
    public abstract class Lifecycle {
    public abstract void addObserver(LifecycleObserver
    observer);
    public abstract void removeObserver(LifecycleObserver
    observer);
    public abstract State getCurrentState();
    public enum Event {
    ON_CREATE, ON_START, ...ON_ANY
    }
    public enum State {
    DESTROYED, INITIALIZED, CREATED, STARTED, RESUMED;
    public boolean isAtLeast(State state) {
    return compareTo(state) >= 0;
    }
    }
    }
    

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24. LifecycleΫϥε
    public abstract class Lifecycle {
    public abstract void addObserver(LifecycleObserver
    observer);
    public abstract void removeObserver(LifecycleObserver
    observer);
    public abstract State getCurrentState();
    public enum Event {
    ON_CREATE, ON_START, ...ON_ANY
    }
    public enum State {
    DESTROYED, INITIALIZED, CREATED, STARTED, RESUMED;
    public boolean isAtLeast(State state) {
    return compareTo(state) >= 0;
    }
    }
    }
    

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25. https://developer.android.com/topic/libraries/architecture/lifecycle.html
    class MyLocationListener implements LifecycleObserver {
    public void enable() {
    enabled = true;
    if (lifecycle.getState().isAtLeast(STARTED)) {
    // connect if not connected
    }
    }
    

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26. Deep dive into Lifecycles
    

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27. 1. LifecycleObserverͷ಺෦࣮૷͸ʁ
    

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28. AnnotationProcessorʹΑΓࣗಈੜ੒͞ΕͨFooObserver
    public class FooObserver_LifecycleAdapter implements
    GenericLifecycleObserver {
    final FooObserver mReceiver;
    ...
    @Override
    public void onStateChanged(LifecycleOwner owner,
    Lifecycle.Event event) {
    if (event == Lifecycle.Event.ON_START) {
    mReceiver.start();
    }
    if (event == Lifecycle.Event.ON_STOP) {
    mReceiver.stop();
    }
    }
    }
    ※GenericLifecycleObserver͸@hideͳΫϥε
    

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29. LifecycleRegistryΫϥε
    public class LifecycleRegistry extends Lifecycle {
    @Override
    public void addObserver(LifecycleObserver observer) {
    ObserverWithState observerWithState = new
    ObserverWithState(observer);
    mObserverSet.putIfAbsent(observer,
    observerWithState);
    observerWithState.sync();
    }
    ...
    class ObserverWithState {
    private State mObserverCurrentState = INITIALIZED;
    private GenericLifecycleObserver mCallback;
    ObserverWithState(LifecycleObserver observer) {
    mCallback = Lifecycling.getCallback(observer);
    }
    }
    
    

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30. LifecycleRegistryΫϥε
    public class LifecycleRegistry extends Lifecycle {
    @Override
    public void addObserver(LifecycleObserver observer) {
    ObserverWithState observerWithState = new
    ObserverWithState(observer);
    mObserverSet.putIfAbsent(observer,
    observerWithState);
    observerWithState.sync();
    }
    ...
    class ObserverWithState {
    private State mObserverCurrentState = INITIALIZED;
    private GenericLifecycleObserver mCallback;
    ObserverWithState(LifecycleObserver observer) {
    mCallback = Lifecycling.getCallback(observer);
    }
    }
    

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31. LifecyclingΫϥε
    class Lifecycling {
    static GenericLifecycleObserver getCallback(Object object)
    {
    ...
    final Class> klass = object.getClass();
    ...
    cachedConstructor =
    getGeneratedAdapterConstructor(klass);
    ...
    return new ReflectiveGenericLifecycleObserver(object);
    ...
    static String getAdapterName(String className) {
    return className.replace(".", "_") +
    "_LifecycleAdapter";
    }
    

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32. 2. Lifecycle.Eventͷൃ৴͸ҰମͲ͔͜Βʁ
    

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33. AndroidManifest (packaged)ʹո͛͠ͳprovider͕…
    
    
    ...
    android:name="android.arch.lifecycle.LifecycleRuntimeTroja
    nProvider"
    android:exported="false"
    android:multiprocess="true"
    android:authorities="com.ogaclejapan.samples.lifecycle-
    trojan" />
    
    
    (*´ŋωŋ`)̾̌˓( ͤΊͯެࣜυΩϡϝϯτʹॻ͍ͯ͘ΕΑ͒͒ɻɻɻ)
    
    

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34. LifecycleRuntimeTrojanProviderΫϥε
    public class LifecycleRuntimeTrojanProvider extends
    ContentProvider {
    @Override
    public boolean onCreate() {
    LifecycleDispatcher.init(getContext());
    ProcessLifecycleOwner.init(getContext());
    return true;
    }
    ...
    Firebase͕ར༻͍ͯ͠ΔContentProviderΛར༻ͨ͠ॳظԽHack
    ʢ҉໧తʹApplicationͷonCreateΑΓ΋ઌʹॳظԽΛ࣮ߦͰ͖Δʣ
    ʮHow does Firebase initialize on Android?ʯ
    https://firebase.googleblog.com/2016/12/how-does-firebase-initialize-on-android.html
    

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35. LifecycleDispatcherΫϥεͰ΍͍ͬͯΔ͜ͱʢͬ͘͟Γʣ
    • initॲཧͰActivityLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onActivityCreatedͰ”ReportFragment”ͷ௥Ճͱ
    FragmentLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onFragmentCreatedͰFragment͕
    LifecycleRegistryOwnerΛ࣮૷͍ͯ͠Ε
    ͹”DestructionReportFragment”Λ௥Ճ
    • ֤LifecycleCallbacks಺ͰLifecycleRegistryOwnerΛ࣮૷
    ͍ͯ͠Ε͹LifecycleRegistryʹରͯ͠”markState()”
    ͱ”handleLifecycleEvent()”ͷߋ৽ΛҰ෦୲͏
    

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36. LifecycleDispatcherΫϥεͰ΍͍ͬͯΔ͜ͱʢͬ͘͟Γʣ
    • initॲཧͰActivityLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onActivityCreatedͰ”ReportFragment”ͷ௥Ճͱ
    FragmentLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onFragmentCreatedͰFragment͕
    LifecycleRegistryOwnerΛ࣮૷͍ͯ͠Ε
    ͹”DestructionReportFragment”Λ௥Ճ
    • ֤LifecycleCallbacks಺ͰLifecycleRegistryOwnerΛ࣮૷
    ͍ͯ͠Ε͹LifecycleRegistryʹରͯ͠”markState()”
    ͱ”handleLifecycleEvent()”ͷߋ৽ΛҰ෦୲͏
    

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37. LifecycleDispatcherΫϥεͰ΍͍ͬͯΔ͜ͱʢͬ͘͟Γʣ
    • initॲཧͰActivityLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onActivityCreatedͰ”ReportFragment”ͷ௥Ճͱ
    FragmentLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onFragmentCreatedͰFragment͕
    LifecycleRegistryOwnerΛ࣮૷͍ͯ͠Ε
    ͹”DestructionReportFragment”Λ௥Ճ
    • ֤LifecycleCallbacks಺ͰLifecycleRegistryOwnerΛ࣮૷
    ͍ͯ͠Ε͹LifecycleRegistryʹରͯ͠”markState()”
    ͱ”handleLifecycleEvent()”ͷߋ৽ΛҰ෦୲͏
    

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38. LifecycleDispatcherΫϥεͰ΍͍ͬͯΔ͜ͱʢͬ͘͟Γʣ
    • initॲཧͰActivityLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onActivityCreatedͰ”ReportFragment”ͷ௥Ճͱ
    FragmentLifecycleCallbacks΁ίʔϧόοΫొ࿥
    • onFragmentCreatedͰFragment͕
    LifecycleRegistryOwnerΛ࣮૷͍ͯ͠Ε
    ͹”DestructionReportFragment”Λ௥Ճ
    • ֤LifecycleCallbacks಺ͰLifecycleRegistryOwnerΛ࣮૷
    ͍ͯ͠Ε͹LifecycleRegistryʹରͯ͠”markState()”
    ͱ”handleLifecycleEvent()”ͷߋ৽ΛҰ෦୲͏
    

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39. ReportFragmentΫϥε
    public class ReportFragment extends Fragment {
    public void onActivityCreated(Bundle savedInstanceState)
    {
    ...
    dispatch(Lifecycle.Event.ON_CREATE);
    }
    ...
    private void dispatch(Lifecycle.Event event) {
    if (getActivity() instanceof LifecycleRegistryOwner)
    {
    ((LifecycleRegistryOwner)
    getActivity()).getLifecycle().handleLifecycleEvent(event);
    }
    }
    LifecycleRegistryOwnerΛ࣮૷ͨ͠Activity΁ͷϥΠϑαΠΫϧมߋ
    Πϕϯτ͸͢΂ͯReportFragment಺Ͱݺ͹Ε͍ͯΔ
    

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40. ͏ʔΜɺ૝૾Ҏ্ʹཪͰ৭ʑ΍ͬͯͨɻɻ
    

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41. LiveData
    

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42. LiveDataΫϥε
    • ஋ͷߋ৽Λ҆શʹObserver΁௨஌Մೳ

    -> LifecycleOwnerͷState͕STARTED or RESUMED࣌ͷΈ௨஌
    • Lifecycle-aware components. 

    -> LifecycleOwnerͷState͕DESTROYED࣌͸observerΛࣗಈղআ
    public abstract class LiveData {
    @MainThread
    public void observe(LifecycleOwner owner, Observer
    observer) { ... }
    protected void postValue(T value) { ... }
    @MainThread
    protected void setValue(T value) { ... }
    public T getValue() { ... }
    ...
    }
    

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43. LiveDataͷ࢓૊Έ
    State: STARTED or RESUMED
    State: CREATED
    Observer LiveData
    setValue(“Foo”) : version = 0
    observe()
    onChange(“Foo”)
    setValue(“Bar”) : version = 1
    pending
    onChange(“Bar”)
    lastVersion = 0
    lastVersion = 1
    setValue(“CA”) : version = 2
    lastVersion = -1 initial : version = -1
    setValue(“apk”) : version = 3
    onChange(“apk”)
    lastVersion = 3
    pending
    ※version͕ಉ͡ͳͷͰ௨஌͠ͳ͍
    

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44. MutableLiveDataΫϥε
    public class MutableLiveData extends LiveData {
    @Override
    public void postValue(T value) {
    super.postValue(value);
    }
    @Override
    public void setValue(T value) {
    super.setValue(value);
    }
    }
    • postValue() / setValue()Λpublicείʔϓ΁มߋ

    -> ObservableField΍BehaviorSubjectΈ͍ͨͳ஋ͷมߋݕ஌͕Ͱ
    ͖ΔϓϩύςΟͱͯ͠࢖͑ͦ͏
    

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45. TimerLiveDataΫϥε (Custom)
    public class TimerLiveData extends LiveData {
    private final Runnable TimeUpdater = new Runnable() {
    @Override
    public void run() {
    setValue(elapsedTime += 1000L);
    handler.postDelayed(TimeUpdater, 1000L);
    }
    };
    private final Handler handler = new Handler();
    private long elapsedTime = 0L;
    @Override
    protected void onActive() {
    handler.postDelayed(TimeUpdater, 1000L);
    }
    @Override
    protected void onInactive() {
    handler.removeCallbacks(TimeUpdater);
    }
    }
    

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46. TimerLiveDataΫϥε (Custom)
    public class TimerLiveData extends LiveData {
    private final Runnable TimeUpdater = new Runnable() {
    @Override
    public void run() {
    setValue(elapsedTime += 1000L);
    handler.postDelayed(TimeUpdater, 1000L);
    }
    };
    private final Handler handler = new Handler();
    private long elapsedTime = 0L;
    @Override
    protected void onActive() {
    handler.postDelayed(TimeUpdater, 1000L);
    }
    @Override
    protected void onInactive() {
    handler.removeCallbacks(TimeUpdater);
    }
    }
    

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47. LiveData userName =
    Transformations.map(userLiveData, user -> {
    user.name + " " + user.lastName
    });
    Transformations
    MediatorLiveData
    https://developer.android.com/reference/android/arch/lifecycle/MediatorLiveData.html
    https://developer.android.com/reference/android/arch/lifecycle/Transformations.html
    -> ಠࣗͳTransformationsΛ৽ͨʹఆٛ͢Δͱ͖ʹ࢖͑Δ
    -> LiveDataͷ஋ΛՃ޻͢Δ (ݱঢ়͸map, switchMapͷΈ)
    

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48. ViewModel
    

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49. ViewModelΫϥε
    public abstract class ViewModel {
    protected void onCleared() {
    }
    }
    ViewModelProviders.of(activity)
    .get(FooViewModel.class)
    ViewModelStores.of(activity)
    HolderFragmentੜ੒

    -> setRetainInstance(true)
    

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50. https://speakerdeck.com/ogaclejapan/how-to-keep-data-between-orientation-changes
    

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51. ViewModelΫϥεར༻࣌ͷ஫ҙ఺
    • Activity࠶ੜ੒Λލ͍Ͱσʔλ͕อ࣋͞ΕΔͷͰɺActivity΍
    ViewɺResourceͳͲΛอ࣋͢ΔͱϝϞϦϦʔΫ͢Δ :(
    Ͳ͏ͯ͠΋ViewModel಺ͰContextΛ࢖͍͍ͨͱ͖ʹ͸Application
    ΫϥεΛอ࣋͢ΔAndroidViewModelΛ࢖͍·͠ΐ͏
    public class AndroidViewModel extends ViewModel {
    private Application mApplication;
    public AndroidViewModel(Application application) {
    mApplication = application;
    }
    public T getApplication() {
    return (T) mApplication;
    }
    }
    

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52. Architecture componentsͰਪ঑͞ΕΔΞʔΩςΫνϟ
    https://developer.android.com/topic/libraries/architecture/guide.html#the_final_architecture
    

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53. ࢀߟࢿྉ
    

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54. • ެࣜΨΠυ
    https://developer.android.com/topic/libraries/architecture/index.html
    • ެࣜαϯϓϧ
    https://github.com/googlesamples/android-architecture-components
    Architecture Components ࢀߟϦϯΫ
    • I/O ηογϣϯಈը
    Architecture Components - Introduction

    https://www.youtube.com/watch?v=FrteWKKVyzI
    Architecture Components - Solving the Lifecycle Problem

    https://www.youtube.com/watch?v=bEKNi1JOrNs
    

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55. ࠓޙʹظ଴ʂʂ
    

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