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INTRODUCTION TO AGERA
HIROSHI KUROKAWA (FABLIC, INC.)
SHIBUYA.APK #7, MAY 9TH, 2016
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SHIBUYA.APK #7 (2016-05-09)
AGENDA
▸ Brief introduction of Agera
▸ Simple usage
▸ Advanced usage: dealing with an existing callback API
▸ Advanced usage: repository chain
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SHIBUYA.APK #7 (2016-05-09)
WHAT’S AGERA
▸ Published by Google
▸ A flavour of 0-arguments reactive programming
▸ Push event, pull data
▸ For consumption by Android application components
https://github.com/google/agera
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SHIBUYA.APK #7 (2016-05-09)
REFERENCE
▸ GitHub Wiki
▸ https://github.com/google/agera/wiki
▸ Advanced RxJava: Google Agera vs. ReactiveX
▸ http://akarnokd.blogspot.jp/2016/04/google-agera-vs-
reactivex.html
▸ dex.fm - 1.5: Agera
▸ https://dexfm.tumblr.com/post/143911768293/15-agera
▸ Sample code used in this talk
▸ https://github.com/hkurokawa/AgeraSample
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SHIBUYA.APK #7 (2016-05-09)
BASIC CONCEPT
▸ Observable
▸ Event source (do not carry any data)
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SHIBUYA.APK #7 (2016-05-09)
BASIC CONCEPT
▸ Observable
▸ Event source (do not carry any data)
▸ Updatable
▸ Observes an Observable
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SHIBUYA.APK #7 (2016-05-09)
BASIC CONCEPT
▸ Observable
▸ Event source (do not carry any data)
▸ Updatable
▸ Observes an Observable
▸ Supplier
▸ Provides data
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SHIBUYA.APK #7 (2016-05-09)
BASIC CONCEPT
▸ Observable
▸ Event source (do not carry any data)
▸ Updatable
▸ Observes an Observable
▸ Supplier
▸ Provides data
▸ Repository
▸ Both Observable and Supplier
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
SETUP AN OBSERVABLE TRIGGERED
WHEN REFRESHED
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
SETUP A REPOSITORY
TO FETCH TWEETS
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
START WITH ABSENT
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
OBSERVE ONREFRESH,
HANDLING A CONSECUTIVE EVENTS
AS AN EVENT
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
RETRIEVES TWEETS ON ANOTHER THREAD
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
BUILD A REPOSITORY
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
CREATE A RECYCLERVIEW ADAPTER
RECEIVING TWEETS
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}
SET THE ADAPTER
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// OnRefresh observable
final OnRefreshObservable refreshObservable = new OnRefreshObservable();
swipeRefreshLayout.setOnRefreshListener(refreshObservable);
// Tweets supplier and repository
final TweetsSupplier tweetsSupplier = new TweetsSupplier();
tweetsRepository = Repositories
.repositoryWithInitialValue(Result.>absent())
.observe(refreshObservable)
.onUpdatesPerLoop()
.goTo(networkExecutor)
.thenGetFrom(tweetsSupplier)
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
final RecyclerView list = binding.list;
list.setAdapter(listAdapter);
list.setLayoutManager(new LinearLayoutManager(this));
}.
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}.
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}.
@Override
protected void onResume() {
super.onResume();
// Start loading
listAdapter.startObserving();
swipeRefreshLayout.post(this::update);
// Start listening to the update
tweetsRepository.addUpdatable(this);
}
@Override
protected void onPause() {
super.onPause();
listAdapter.stopObserving();
// Stop listening to the update
tweetsRepository.removeUpdatable(this);
}
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}
@Override
protected void onResume() {
super.onResume();
// Start loading
listAdapter.startObserving();
swipeRefreshLayout.post(this::update);
// Start listening to the update
tweetsRepository.addUpdatable(this);
}
@Override
protected void onPause() {
super.onPause();
listAdapter.stopObserving();
// Stop listening to the update
tweetsRepository.removeUpdatable(this);
}
START OBSERVING,
SHOW REFRESHING PROGRESS BAR
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}
@Override
protected void onResume() {
super.onResume();
// Start loading
listAdapter.startObserving();
swipeRefreshLayout.post(this::update);
// Start listening to the update
tweetsRepository.addUpdatable(this);
}
@Override
protected void onPause() {
super.onPause();
listAdapter.stopObserving();
// Stop listening to the update
tweetsRepository.removeUpdatable(this);
}
STOP OBSERVING
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}.
@Override
protected void onResume() {
super.onResume();
// Start loading
listAdapter.startObserving();
swipeRefreshLayout.post(this::update);
// Start listening to the update
tweetsRepository.addUpdatable(this);
}.
@Override
protected void onPause() {
super.onPause();
listAdapter.stopObserving();
// Stop listening to the update
tweetsRepository.removeUpdatable(this);
}..
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}.
@Override
protected void onResume() {
...
}.
@Override
protected void onPause() {
...
}..
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SHIBUYA.APK #7 (2016-05-09)
SIMPLE USAGE
public class MainActivity extends AppCompatActivity implements Updatable {
...
@Override
protected void onCreate(Bundle savedInstanceState) {
...
}.
@Override
protected void onResume() {
...
}.
@Override
protected void onPause() {
...
}..
@Override
public void update() {
if (tweetsSearchRepository.get().isAbsent()) {
swipeRefreshLayout.setRefreshing(true);
} else if (tweetsSearchRepository.get().failed()) {
Toast.makeText(this, R.string.error, Toast.LENGTH_SHORT).show();
swipeRefreshLayout.setRefreshing(false);
} else {
swipeRefreshLayout.setRefreshing(false);
}
}
SHOW REFRESHING PROGRESS BAR
WHILE UPDATING
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SHIBUYA.APK #7 (2016-05-09)
LESSONS LEARNED #1
▸ It’s NOT that simple!
▸ Trigger (OnRefreshObservable) doesn’t provide any data
▸ The thread to execute the supplier can be controlled with goTo()
method
▸ CompiledRepository is useful but the methods are order-sensitive
▸ ex. getFrom() vs. thenGetFrom()
▸ Support for RecyclerView or other Android stuff is great
▸ Call addUpdatable() and removeUpdatable() in onResume() and
onPause()
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
▸ Dealing with a callback API
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {}));
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
▸ Dealing with a callback API
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
@Override
public void success(Result result) {
}.
@Override
public void failure(TwitterException exception) {
}.
}));
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
▸ Dealing with a callback API
▸ Wrap with a Repository
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
@Override
public void success(Result searchResult) {
}.
@Override
public void failure(TwitterException exception) {
}.
}));
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
@Override.
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
@Override
public void success(Result searchResult) {
result = Result.success(searchResult.data.tweets);
dispatchUpdate();
}.
@Override
public void failure(TwitterException exception) {
result = Result.failure(exception);
dispatchUpdate();
}.
}));
}..
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
@Override.
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
….
}));
}..
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
@Override
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
….
}));
}.
@NonNull
@Override
public Result> get() {
return result;
}.
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
@Override
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
….
}));
}.
@NonNull
@Override
public Result> get() {
return result;
}.
@Override
protected void observableActivated() {
update();
}.
CALLED WHEN
THE FIRST UPDATABLE IS ADDED
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
@Override
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
….
}));
}.
@NonNull
@Override
public Result> get() {
return result;
}.
@Override
protected void observableActivated() {
update();
}.
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SHIBUYA.APK #7 (2016-05-09)
ONE STEP FURTHER - CALLBACK API
class TweetsSearchRepository extends BaseObservable implements
Repository>>, Updatable {
@Override
public void update() {
final TwitterApiClient client = Twitter.getApiClient(session);
client.getSearchService().tweets("#shibuyaapk",
new GuestCallback<>(new Callback() {
….
}));
}.
@NonNull
@Override
public Result> get() {
return result;
}.
@Override
protected void observableActivated() {
update();
}.
}
KEEP THE THREADING CONTRACT
BETWEEN OBSERVABLE AND UPDATABLE
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SHIBUYA.APK #7 (2016-05-09)
LESSONS LEARNED #2
▸ If you have to deal with an existing callback API, wrap the
API with Repository
▸ Inherit BaseObservable if possible
▸ Do not forget to override observableActivated()
▸ Make sure your repository is as simple as possible
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
▸ Load the next page when scrolling down to the bottom of
the list
▸ OnBottomObservable
▸ Fire an event when the bottom of the list is visible
▸ TweetsRequestSupplier
▸ Provide the maxId query
▸ OnBottomObservable triggers the search and the
retrieved tweets are appended to the current list
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
// Repository to store the entire list
final Repository>> tweetsRepository =
Repositories.repositoryWithInitialValue(Result.>absent())
.observe(tweetsSearchRepository)
.onUpdatesPerLoop()
.thenMergeIn(tweetsSearchRepository, (current, searchResult) -> {
if (current.isAbsent() || current.failed()) {
return searchResult;
}.
final List ls = new ArrayList<>(current.get());
if (searchResult.succeeded()) {
ls.addAll(searchResult.get());
}.
return Result.success(ls);
})
.compile();
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
// Repository to store the entire list
final Repository>> tweetsRepository =
Repositories.repositoryWithInitialValue(Result.>absent())
.observe(tweetsSearchRepository)
.onUpdatesPerLoop()
.thenMergeIn(tweetsSearchRepository, (current, searchResult) -> {
if (current.isAbsent() || current.failed()) {
return searchResult;
}.
final List ls = new ArrayList<>(current.get());
if (searchResult.succeeded()) {
ls.addAll(searchResult.get());
}.
return Result.success(ls);
})
.compile();
MERGE THE RETRIEVED TWEETS
INTO THE CURRENT LIST
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
// Repository to store the entire list
final Repository>> tweetsRepository =
Repositories.repositoryWithInitialValue(Result.>absent())
.observe(tweetsSearchRepository)
.onUpdatesPerLoop()
.thenMergeIn(tweetsSearchRepository, (current, searchResult) -> {
if (current.isAbsent() || current.failed()) {
return searchResult;
}.
final List ls = new ArrayList<>(current.get());
if (searchResult.succeeded()) {
ls.addAll(searchResult.get());
}.
return Result.success(ls);
})
.compile();
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
// Repository to store the entire list
final Repository>> tweetsRepository =
Repositories.repositoryWithInitialValue(Result.>absent())
.observe(tweetsSearchRepository)
.onUpdatesPerLoop()
.thenMergeIn(tweetsSearchRepository, (current, searchResult) -> {
if (current.isAbsent() || current.failed()) {
return searchResult;
}.
final List ls = new ArrayList<>(current.get());
if (searchResult.succeeded()) {
ls.addAll(searchResult.get());
}.
return Result.success(ls);
})
.compile();
listAdapter = RepositoryAdapter.repositoryAdapter()
.add(tweetsRepository, new TweetPresenter())
.build();
list.setAdapter(listAdapter);
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SHIBUYA.APK #7 (2016-05-09)
ONE MORE STEP - REPOSITORY CHAIN
@Override
protected void onResume() {
super.onResume();
// Start loading
listAdapter.startObserving();
swipeRefreshLayout.post(this::update);
// Start listening to the update
refreshObservable.addUpdatable(tweetsSearchRepository);
refreshObservable.addUpdatable(searchRequest);
onBottomObservable.addUpdatable(tweetsSearchRepository);
tweetsSearchRepository.addUpdatable(this);
}
@Override
protected void onPause() {
super.onPause();
// Stop listening to the update
refreshObservable.removeUpdatable(tweetsSearchRepository);
refreshObservable.removeUpdatable(searchRequest);
onBottomObservable.removeUpdatable(tweetsSearchRepository);
tweetsSearchRepository.removeUpdatable(this);
listAdapter.stopObserving();
}
MANY REGISTRATIONS/UNREGISTRATIONS
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SHIBUYA.APK #7 (2016-05-09)
LESSONS LEARNED #4
▸ You can chain repositories to compose a flow
▸ The Updatables have to be added/removed at onResume()/
onPuase()
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SHIBUYA.APK #7 (2016-05-09)
COMPARE AGERA TO RXJAVA (JUST AN IMPRESSION)
▸ 0-arguments reactive programming
▸ Not so bad in Android app usage
▸ Non-rich operators
▸ No combineLatest() or zipWith() operator
▸ You can use Functions to do map, filter, etc.
▸ Handling of the subscriptions seems not so smart
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SHIBUYA.APK #7 (2016-05-09)
CONCLUSION
▸ Pros
▸ Very focusing on Android app usage (e.g. RecyclerViewAdapter,
SqlDatabaseFunctions, HttpFunctions)
▸ Maybe easy and effective for a simple requirement
▸ Cons
▸ Needs some time for developer to get used to the APIs
▸ Operators are not rich (for now)
▸ Can be complicated for a complicated requirement (that’s the way
of our life)