Rxjava 简明教程
RxJava - Transforming Operators
以下是用于转换从 Observable 发出的项的操作符。
Following are the operators which are used to transform an item emitted from an Observable.
Sr.No. |
Operator & Description |
1 |
Buffer Gathers items from Observable into bundles periodically and then emit the bundles rather than items. |
2 |
FlatMap Used in nested observables. Transforms items into Observables. Then flatten the items into single Observable. |
3 |
GroupBy Divide an Observable into set of Observables organized by key to emit different group of items. |
4 |
Map Apply a function to each emitted item to transform it. |
5 |
Scan Apply a function to each emitted item, sequentially and then emit the successive value. |
6 |
Window Gathers items from Observable into Observable windows periodically and then emit the windows rather than items. |
Transforming Operator Example
在任意编辑器中使用任何您选择的语言（如 C:\>RxJava) 创建以下 Java 程序。
Create the following Java program using any editor of your choice in, say, C:\> RxJava.
ObservableTester.java
import io.reactivex.Observable;
//Using map operator to transform an Observable
public class ObservableTester {
public static void main(String[] args) {
String[] letters = {"a", "b", "c", "d", "e", "f", "g"};
final StringBuilder result = new StringBuilder();
Observable<String> observable = Observable.fromArray(letters);
observable
.map(String::toUpperCase)
.subscribe( letter -> result.append(letter));
System.out.println(result);
}
}