RXjava 创建操作符

just:将一个或多个对象转换成发射这个或这些对象的一个Observable

Observable.just(1,55,99,33)
.subscribe(new Subscriber<Integer>() {
@Override
public void onCompleted() {

}

@Override
public void onError(Throwable e) {

}

@Override
public void onNext(Integer integer) {
Log.e(TAG,"**"+ integer);
}
});

03-16 09:55:14.973 2902-2902/com.iwith.smart E/RxjavaActivity: **1
03-16 09:55:14.973 2902-2902/com.iwith.smart E/RxjavaActivity: **55
03-16 09:55:14.973 2902-2902/com.iwith.smart E/RxjavaActivity: **99
03-16 09:55:14.973 2902-2902/com.iwith.smart E/RxjavaActivity: **33

from:将一个Iterable, 一个Future, 或者一个数组转换成一个Observable

List<String> list = new ArrayList<String>();
list.add("111");
list.add("222");
list.add("333");
Observable.from(list)
.subscribe(new Subscriber<String>() {
@Override
public void onCompleted() {

}

@Override
public void onError(Throwable e) {

}

@Override
public void onNext(String s) {
Log.e(TAG,s);
}
});

03-16 09:56:49.562 2902-2902/com.iwith.smart E/RxjavaActivity: 111
03-16 09:56:49.562 2902-2902/com.iwith.smart E/RxjavaActivity: 222
03-16 09:56:49.563 2902-2902/com.iwith.smart E/RxjavaActivity: 333

repeat:创建一个重复发射指定数据或数据序列的Observable

String[] items = {"just1","just2","just3","just4","just5","just6"};
Observable.from(items)
.repeat()
.subscribe(new Subscriber<String>() {
@Override
public void onCompleted() {

}

@Override
public void onError(Throwable e) {

}

@Override
public void onNext(String s) {
Log.e(TAG,s);
}
});

2 7008-7008/com.iwith.smart E/RxjavaActivity: just1

2 7008-7008/com.iwith.smart E/RxjavaActivity: just2

2 7008-7008/com.iwith.smart E/RxjavaActivity: just3

2 7008-7008/com.iwith.smart E/RxjavaActivity: just4

2 7008-7008/com.iwith.smart E/RxjavaActivity: just5

2 7008-7008/com.iwith.smart E/RxjavaActivity: just6

2 7008-7008/com.iwith.smart E/RxjavaActivity: just1

2 7008-7008/com.iwith.smart E/RxjavaActivity: just2

2 7008-7008/com.iwith.smart E/RxjavaActivity: just3

2 7008-7008/com.iwith.smart E/RxjavaActivity: just4

2 7008-7008/com.iwith.smart E/RxjavaActivity: just5

2 7008-7008/com.iwith.smart E/RxjavaActivity: just6

2 7008-7008/com.iwith.smart E/RxjavaActivity: just1

..........

加参数:循环两次

Observable.from(items)
.repeat(2)
.subscribe(new Subscriber<String>() {
@Override
public void onCompleted() {

}

@Override
public void onError(Throwable e) {

}

@Override
public void onNext(String s) {
Log.e(TAG,s);
}
});

03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just1
03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just2
03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just3
03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just4
03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just5
03-16 10:03:23.199 11764-11764/com.iwith.smart E/RxjavaActivity: just6
03-16 10:03:23.200 11764-11764/com.iwith.smart E/RxjavaActivity: just1
03-16 10:03:23.200 11764-11764/com.iwith.smart E/RxjavaActivity: just2
03-16 10:03:23.200 11764-11764/com.iwith.smart E/RxjavaActivity: just3
03-16 10:03:23.201 11764-11764/com.iwith.smart E/RxjavaActivity: just4
03-16 10:03:23.201 11764-11764/com.iwith.smart E/RxjavaActivity: just5
03-16 10:03:23.201 11764-11764/com.iwith.smart E/RxjavaActivity: just6

range:创建一个发射指定范围的整数序列的Observable

Observable.range(2,5)
.subscribe(new Action1<Integer>() {
@Override
public void call(Integer integer) {
Log.e(TAG,"**"+integer);
}
});

03-16 10:24:26.548 1307-1307/com.iwith.smart E/RxjavaActivity: **2
03-16 10:24:26.548 1307-1307/com.iwith.smart E/RxjavaActivity: **3
03-16 10:24:26.549 1307-1307/com.iwith.smart E/RxjavaActivity: **4
03-16 10:24:26.549 1307-1307/com.iwith.smart E/RxjavaActivity: **5
03-16 10:24:26.549 1307-1307/com.iwith.smart E/RxjavaActivity: **6

interval:创建一个按照给定的时间间隔发射整数序列的Observable

Observable.interval(1, TimeUnit.SECONDS)
.subscribe(new Action1<Long>() {
@Override
public void call(Long aLong) {
Log.e(TAG,"**"+aLong);
}
});

03-16 10:24:58.566 1307-3872/com.iwith.smart E/RxjavaActivity: **0
03-16 10:24:59.566 1307-3872/com.iwith.smart E/RxjavaActivity: **1
03-16 10:25:00.566 1307-3872/com.iwith.smart E/RxjavaActivity: **2
03-16 10:25:01.565 1307-3872/com.iwith.smart E/RxjavaActivity: **3
03-16 10:25:02.566 1307-3872/com.iwith.smart E/RxjavaActivity: **4
03-16 10:25:03.565 1307-3872/com.iwith.smart E/RxjavaActivity: **5
.......

timer:创建一个在给定的延时之后发射单个数据的Observable

Observable.timer(1, TimeUnit.SECONDS)
.subscribe(new Action1<Long>() {
@Override
public void call(Long aLong) {
Log.e(TAG,"**"+aLong);
}
});

03-16 10:26:08.677 4910-5114/com.iwith.smart E/RxjavaActivity: **0

tmpty:创建一个什么都不做直接通知完成的Observable

Observable.just(1,2,3)
.empty()
.subscribe(new Subscriber<Object>() {
@Override
public void onCompleted() {
Log.e(TAG,"onCompleted");

}

@Override
public void onError(Throwable e) {
Log.e(TAG,"onError");
}

@Override
public void onNext(Object o) {
Log.e(TAG,"onNext");
}
});

03-16 10:26:48.430 4910-4910/com.iwith.smart E/RxjavaActivity: onCompleted

error:创建一个什么都不做直接通知错误的Observable

Observable.just(1,2,3)
.error(new RuntimeException())
.subscribe(new Subscriber<Object>() {
@Override
public void onCompleted() {
Log.e(TAG,"onCompleted");
}

@Override
public void onError(Throwable e) {
Log.e(TAG,"onError");
}

@Override
public void onNext(Object o) {
Log.e(TAG,"onNext");
}
});

03-16 10:27:13.626 4910-4910/com.iwith.smart E/RxjavaActivity: onError

never:创建一个不发射任何数据的Observable

Observable.just(1,2,3)
.never()
.subscribe(new Subscriber<Object>() {
@Override
public void onCompleted() {
Log.e(TAG,"onCompleted");
}

@Override
public void onError(Throwable e) {
Log.e(TAG,"onError");
}

@Override
public void onNext(Object o) {
Log.e(TAG,"onNext");
}
});

无任何打印

create：使用一个函数从头创建一个Observable

Observable.create(new Observable.OnSubscribe<String>() {
@Override
public void call(Subscriber<? super String> subscriber) {
subscriber.onNext("onNext1");
subscriber.onNext("onNext2");
subscriber.onNext("onNext3");
subscriber.onCompleted();
}
}).subscribe(new Subscriber<String>() {
@Override
public void onCompleted() {
Log.e(TAG,"onCompleted");
}

@Override
public void onError(Throwable e) {

}

@Override
public void onNext(String s) {
Log.e(TAG,s);
}
});

03-16 10:31:15.594 4910-4910/com.iwith.smart E/RxjavaActivity: onNext1
03-16 10:31:15.594 4910-4910/com.iwith.smart E/RxjavaActivity: onNext2
03-16 10:31:15.595 4910-4910/com.iwith.smart E/RxjavaActivity: onNext3
03-16 10:31:15.595 4910-4910/com.iwith.smart E/RxjavaActivity: onCompleted