我正在开发一个文件下载器，我正在大致像这样构建我的流
someobservable ---------------------------- this stream can generate 1000 of
downloadable urls
.flatmap(urltodownload -> {
downloadStream(value); --------------------- this steam can pause resume and
maybe cancel
}.observeOn(AndroidScheduler.mainthread())
.subcribe();
如何在flatmap中暂停或取消某些可观察的创建
答案 0 :(得分：0)
我有一个不优雅的解决方案。我使用CombineLast来dispose任务＆＃39; Disposable Observable挡住package xdean.stackoverflow.rx;
import io.reactivex.Observable;
import io.reactivex.Single;
import io.reactivex.disposables.Disposable;
import io.reactivex.schedulers.Schedulers;
import io.reactivex.subjects.BehaviorSubject;
import io.reactivex.subjects.Subject;
import java.util.List;
import java.util.Random;
import java.util.function.IntPredicate;
import xdean.jex.extra.Pair;
public class Q45540738 {
static Random random = new Random();
public static void main(String[] args) throws InterruptedException {
Single<List<Pair<Integer, Disposable>>> tasks = Observable.range(0, 50)
.map(i -> Pair.of(i, download(i).subscribe()))
.toList();
Subject<IntPredicate> stopers = BehaviorSubject.createDefault(i -> true);
Observable.combineLatest(tasks.toObservable(), stopers, (l, s) -> {
l.removeIf(p -> {
if (s.test(p.getLeft()) == false) {
p.getRight().dispose();
}
return p.getRight().isDisposed();
});
return l;
}).subscribe();
Thread.sleep(2000);
stopers.onNext(i -> i % 2 == 0);
Thread.sleep(10000);
}
static Observable<Integer> download(int id) {
return Observable.just(random.nextInt(1000) + 500)
.observeOn(Schedulers.computation())
.doOnNext(t -> Thread.sleep(t))
.doOnDispose(() -> System.err.printf("%d task stoped on %s\n", id, Thread.currentThread()))
.doOnNext(t -> System.out.printf("%d task done on %s\n", id, Thread.currentThread()));
}
}
。见代码：
0 task done on Thread[RxComputationThreadPool-1,5,main]
5 task done on Thread[RxComputationThreadPool-6,5,main]
6 task done on Thread[RxComputationThreadPool-7,5,main]
2 task done on Thread[RxComputationThreadPool-3,5,main]
1 task done on Thread[RxComputationThreadPool-2,5,main]
3 task done on Thread[RxComputationThreadPool-4,5,main]
4 task done on Thread[RxComputationThreadPool-5,5,main]
7 task done on Thread[RxComputationThreadPool-8,5,main]
8 task done on Thread[RxComputationThreadPool-1,5,main]
9 task stoped on Thread[main,5,main]
11 task stoped on Thread[main,5,main]
13 task stoped on Thread[main,5,main]
14 task done on Thread[RxComputationThreadPool-7,5,main]
15 task stoped on Thread[main,5,main]
17 task stoped on Thread[main,5,main]
19 task stoped on Thread[main,5,main]
21 task stoped on Thread[main,5,main]
23 task stoped on Thread[main,5,main]
25 task stoped on Thread[main,5,main]
27 task stoped on Thread[main,5,main]
29 task stoped on Thread[main,5,main]
31 task stoped on Thread[main,5,main]
33 task stoped on Thread[main,5,main]
35 task stoped on Thread[main,5,main]
37 task stoped on Thread[main,5,main]
39 task stoped on Thread[main,5,main]
41 task stoped on Thread[main,5,main]
43 task stoped on Thread[main,5,main]
45 task stoped on Thread[main,5,main]
47 task stoped on Thread[main,5,main]
49 task stoped on Thread[main,5,main]
10 task done on Thread[RxComputationThreadPool-3,5,main]
16 task done on Thread[RxComputationThreadPool-1,5,main]
12 task done on Thread[RxComputationThreadPool-5,5,main]
22 task done on Thread[RxComputationThreadPool-7,5,main]
24 task done on Thread[RxComputationThreadPool-1,5,main]
18 task done on Thread[RxComputationThreadPool-3,5,main]
30 task done on Thread[RxComputationThreadPool-7,5,main]
20 task done on Thread[RxComputationThreadPool-5,5,main]
32 task done on Thread[RxComputationThreadPool-1,5,main]
26 task done on Thread[RxComputationThreadPool-3,5,main]
40 task done on Thread[RxComputationThreadPool-1,5,main]
38 task done on Thread[RxComputationThreadPool-7,5,main]
34 task done on Thread[RxComputationThreadPool-3,5,main]
28 task done on Thread[RxComputationThreadPool-5,5,main]
48 task done on Thread[RxComputationThreadPool-1,5,main]
42 task done on Thread[RxComputationThreadPool-3,5,main]
46 task done on Thread[RxComputationThreadPool-7,5,main]
36 task done on Thread[RxComputationThreadPool-5,5,main]
44 task done on Thread[RxComputationThreadPool-5,5,main]
输出：
x=matrix(runif(10000*2,0,1),10000,2)
test=0
i=0
while(max(test)<7.81 & (6000+i*50)<=nrow(x))
{
y = x[seq(i*50+1,6000+i*50)] # y contains the first 200+i*50 rows of x
ts= runif(1,1,7.9) # random test statistic, enter yours here.
test[i]= sum(ts)
i=i+1
}