I'm using RxAndroid for my app to send a request to the backend and handle the result.
public Observable<Response> getBrands() {
return new Observable<Response>() {
#Override
protected void subscribeActual(Observer<? super Response> observer) {
RequestHelper.GetRequest("getbrands");
}
};
}
public void GetBrands(){
getBrands().subscribeOn(Schedulers.io()).observeOn(AndroidSchedulers.mainThread()).subscribe(new Observer<Response>() {
#Override
public void onSubscribe(Disposable d) {
}
#Override
public void onNext(Response value) {
Log.w("Reactive",value.toString());
Toast.makeText(getActivity(),"Yaaaaay request 5alas",Toast.LENGTH_SHORT).show();
}
#Override
public void onError(Throwable e) {
Log.w("response brands= "+e.toString(),"MyTAG");
}
#Override
public void onComplete() {
}
});
}
RequestHelper.GetRequest("getbrands") is successfully called (Checked backend logs, it's called and returns the response.
the problem is onNext not getting called at all, neither the log or the toast shows up.
Anyone knows why ?
EDIT: i'm using this in a fragment where GetBrands() is called in oncreateview
Just changed my observable function to
public Observable<Response> getBrands() {
return Observable.fromCallable(new Callable<Response>() {
#Override
public Response call() throws Exception {
return RequestHelper.GetRequest("getbrands");
}
});
}
it's working now
Related
While inflating Android view I load a bunch of stuff from the background thread and inflate some views based on network responses. So I am trying to defer some of that tasks using RxJava like this
Single.fromCallable(() -> savedInstanceState)
.delay(50,TimeUnit.MICROSECONDS,AndroidSchedulers.mainThread())
.flatMapCompletable(this::loadVideos)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new CompletableObserver() {
#Override
public void onSubscribe(Disposable d) {
Timber.d("on Subscribe");
}
#Override
public void onComplete() {
Timber.d("on onComplete");
}
#Override
public void onError(Throwable e) {
Timber.d("on onError");
}
});
And the loadVideos method is like this:
private Completable loadVideos(Bundle savedInstanceState) {
return Completable.fromAction(() -> {
videoPresenter.loadVideos(savedInstance);
});
}
What I am finding is onSubscribe() certainly gets called, but method videoPresenter.loadVideos never gets called. Would appreciate if anyone can point out what I am doing wrong.
For my testing, I implemented following test that seems to work...
public class DelayTest {
public static void main(String[] args) throws InterruptedException {
Single.fromCallable(() -> "hello")
.delay(50, TimeUnit.MICROSECONDS)
.flatMapCompletable(new Function<String, CompletableSource>() {
#Override
public CompletableSource apply(String s) throws Exception {
return getFlatMapCompletable();
}
})
.subscribe(new CompletableObserver() {
#Override
public void onSubscribe(Disposable d) {
System.out.println("In onSubscribe");
}
#Override
public void onComplete() {
System.out.println("In onComplete");
}
#Override
public void onError(Throwable e) {
System.out.println("In onError");
}
});
Thread.sleep(200L);
}
private static Completable getFlatMapCompletable() {
return Completable.fromAction(new Action() {
#Override
public void run() throws Exception {
System.out.println("In flatmapCompletable");
}
});
}
}
Delay operator in RxJava is executed in another thread. So the rest of the execution does not wait for this one to be finished.
Take a look to some examples https://github.com/politrons/reactive/blob/master/src/test/java/rx/observables/utils/ObservableDelay.java
I want to send multiple requests over the network and this tutorial
helped but i'm stuck at the latter part .
seems i'm expected to return a value(OrderValues) from onSubscribe,onNext,....
since apply function returns a value. But ....,onNext returns void by default.
Any help?Here is my piece of code
Observable<Restaurant> orderRestaurant= IdentityClient.getAPIService()
.getRestaurantById(restaurantId)
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread());
Observable<Menu> orderMenu= IdentityClient.getAPIService()
.getMenuById(menuId)
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread());
Observable<User> orderUser= IdentityClient.getAPIService()
.getUserById(userId)
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread());
Observable<OrderValues> combineValues=Observable.zip(orderRestaurant,
orderMenu, orderUser,
new Function3<Restaurant, Menu, User, OrderValues>() {
#Override
public OrderValues apply(Restaurant restaurant, Menu menu, User user)
throws Exception {
return new OrderValues(restaurant,menu,user);
}
I get an error here "cannot resolve method 'subscribe anonymous
org.reactivestreams.Subscriber(....OrderValues)
}).subscribe(new Subscriber<OrderValues>() {
#Override
public void onSubscribe(Subscription s) {
}
#Override
public void onNext(OrderValues orderValues) {
}
#Override
public void onError(Throwable t) {
}
#Override
public void onComplete() {
}
});
I'm assuming that you are using RxJava 2.
Use Observer instead of Subscriber. And also do not assign the result to a new Observable (you called it combineValues).
private void myMethod() {
Observable.zip(orderRestaurant, orderMenu, orderUser, new Function3<Restaurant, Menu, User, OrderValues>() {
#Override
public OrderValues apply(#NonNull Restaurant restaurant, #NonNull Menu menu, #NonNull User user) throws Exception {
return new OrderValues(restaurant, menu, user);
}
}).subscribe(new Observer<OrderValues>() {
#Override
public void onSubscribe(Disposable d) {
}
#Override
public void onNext(OrderValues orderValues) {
}
#Override
public void onError(Throwable e) {
}
#Override
public void onComplete() {
}
});
}
}
I'm trying to run a long running task that might fail for some objects in a list I tried retry but it resubscribes to the entire list of observables. I can do nested subscriptions but it seems wrong. Is there any better solution than nesting subscriptions?
Here is my implementation:
public Observable<ReportItemModel> deferReports() {
return Observable.defer(new Callable<ObservableSource<? extends ReportItemModel>>() {
#Override
public ObservableSource<? extends ReportItemModel> call() throws Exception {
return Observable.fromIterable(getReports())
.map(new Function<Report, ReportItemModel>() {
#Override
public ReportItemModel apply(Report report) throws Exception {
return report.getReport();
}
});
}
});
}
reportFactory.deferReports()
.observeOn(AndroidSchedulers.mainThread())
.subscribeOn(Schedulers.io())
.retry()
.subscribe(new Observer<ReportItemModel>() {
#Override
public void onSubscribe(Disposable d) {
}
#Override
public void onNext(ReportItemModel value) {
Log.d(TAG,value.toString());
}
#Override
public void onError(Throwable e) {
}
#Override
public void onComplete() {
}
});
I've an Observable something like this:
#GET("endpoint")
Observable<Something> getSomething();
and Subscriber like this
Subscriber<Something> somethingSubscriber = new Subscriber<Something>() {
public void onCompleted() {
}
public void onError(Throwable e) {
//handle exceptions
}
public void onNext() {
//do something
}
In my OnClickListener associated with a button, i make a subscription
getSomething()
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(somethingSubscriber);
If i don't have an internet connection, onError is called and i do some exception handling. when I press the button again (assume i want to retry), the callback methods do not get called.
I want that onNext / onError callbacks get called everytime I press the button.
There is extention for RxJava. It has a lot of "cool tools", but for handling retrofit errors you can use ResponseOrError class.
So in you case it would looks like:
final PublishSubject<Object> clickSubject = PublishSubject.create();
final Observable<ResponseOrError<Something>> responseOrErrorObservable = clickSubject
.flatMap(new Func1<Object, Observable<ResponseOrError<Something>>>() {
#Override
public Observable<ResponseOrError<Something>> call(Object o) {
return getSomething()
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread())
.compose(ResponseOrError.<Something>toResponseOrErrorObservable());
}
})
.replay(1)
.refCount();
final Observable<Throwable> error = responseOrErrorObservable
.compose(ResponseOrError.<Something>onlyError())
.subscribe(new Action1<Segment>() {
#Override
public void call(Throwable throwable) {
// what to do on error, some toast or what ever yu need
}
});
final Observable<UserInfoResponse> success = responseOrErrorObservable
.compose(ResponseOrError.<Something>onlySuccess())
.subscribe(new Action1<Something>() {
#Override
public void call(Something some) {
// code what to do on success
}
});
And now, into onClick you just need to put clickSubject.onNext(null)
.replay(1).refCount(); needed because there are 2 Observables that uses responseOrErrorObservable, so without it retrofit request will "happens" two times.
You are reusing the same Subscriber. Once you get the onError or a result (so it completes) the subscriber is unsubscribed. Try to pass every time a new subscriber.
use this code
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
getSomething()
.subscribeOn(Schedulers.newThread())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Action1<Something>() {
#Override
public void call(Something something) {
//do something
}
},
new Action1<Throwable>() {
#Override
public void call(Throwable throwable) {
//handle exceptions
}
},
new Action0() {
#Override
public void call() {
}
});
}
});
Addition
or
replace this
Subscriber<Something> somethingSubscriber = new Subscriber<Something>() {
public void onCompleted() {
}
public void onError(Throwable e) {
//handle exceptions
}
public void onNext() {
//do something
}
};
to
Subscriber<String> somethingSubscriber = new Subscriber<String>() {
#Override
public void onCompleted() {
}
#Override
public void onError(Throwable e) {
}
#Override
public void onNext(String s) {
}
};
In my Case onNext() and onError() methods are not getting called because of my model class wrong parsing, I was taking a double object as Integer so NumberFormatException was thrown and nothing was happening after getting the result from retrofit.
I have the following code. It's basically an attempt to send all data from a specific SQLite table to DynamoDB:
Observable.create(new Observable.OnSubscribe<Area>() {
#Override
public void call(Subscriber<? super Area> subscriber) {
try {
for (Area item : areaDao.listAll()) {
subscriber.onNext(item);
}
subscriber.onCompleted();
} catch (Exception e) {
subscriber.onError(e);
}
}
}).flatMap(new Func1<Area, Observable<Area>>() {
#Override
public Observable<Area> call(Area area) {
dynamoDBMapper.save(area);
return Observable.just(area);
}
}).observeOn(
AndroidSchedulers.mainThread()
).doOnError(new Action1<Throwable>() {
#Override
public void call(Throwable throwable) {
Log.w("AreaHandler", "Could not upload area", throwable);
}
}).doOnCompleted(new Action0() {
#Override
public void call() {
Toast.makeText(ctx, R.string.toast_upload_successful, Toast.LENGTH_SHORT).show();
}
}).subscribeOn(
Schedulers.io()
).subscribe(new Action1<Area>() {
#Override
public void call(Area area) {
areaDao.delete(area.getId());
}
});
I'm trying to run it on an emulator with disabled Internet connectivity, and what happens is that the Dynamo client does a couple of (failed) retries, then an exception is thrown and it crashes the app. From what I read in the docs, the exception should be swallowed by doOnError instead of being let out to the wild and killing the process.
What am I missing?
You are grabbing the error in the wrong place. doOnError is for side effects. It does not handle the error.
Option 1. Pass in two Action1
Observable.just(1, 2, 3)
.subscribe(
new Action1<Integer>() {
#Override
public void call(Integer integer) {
System.out.println(integer);
}
},
new Action1<Throwable>() {
#Override
public void call(Throwable throwable) {
System.err.print(throwable);
}
});
Option 2: Pass in an Observer
Observable.just(1, 2, 3)
.subscribe(new Observer<Integer>() {
#Override
public void onCompleted() {
}
#Override
public void onError(Throwable throwable) {
System.err.print(throwable);
}
#Override
public void onNext(Integer integer) {
System.out.println(integer);
}
});