RxJava学习笔记

Bmob中Observable方式

compile 'cn.bmob.android:bmob-sdk:3.5.1'

因为BmobSDK从版本 v3.5.0开始 ，最大的亮点在于：支持Rx链式调用。
PS：bmob-sdk中依赖的rxjava版本是1.1.6，Github上最新的是1.2.3

以下是修改正文字体大小的代码，使用到了concatMap操作符

    /**     * 链式调用，     * @see --> https://github.com/bmob/bmob-android-sdk-demo     * @param size     */    void saveTextSize(final int size){        BmobQuery<SettingBean> bmobQuery = new BmobQuery<>();        bmobQuery.addWhereEqualTo("author", BmobUser.getCurrentUser(UserBean.class));        Observable<List<SettingBean>> observable = bmobQuery.findObjectsObservable(SettingBean.class);        observable.concatMap(new Func1<List<SettingBean>, Observable<?>>() {            @Override            public Observable<?> call(List<SettingBean> settingBeen) {                if(settingBeen.size()==0){                    LogUtil.i(TAG, "concatMap=为0");                    UserBean userBean = BmobUser.getCurrentUser(UserBean.class);                    SettingBean settingBean = new SettingBean();                    settingBean.setAuthor(userBean);                    settingBean.settSize(size);                    return settingBean.saveObservable();                }else{                    LogUtil.i(TAG, "concatMap=不为0");                    UserBean userBean = BmobUser.getCurrentUser(UserBean.class);                    SettingBean settingBean =settingBeen.get(0);                    settingBean.setAuthor(userBean);                    settingBean.settSize(size);                    return settingBean.updateObservable(settingBean.getObjectId());                }            }        }).subscribe(new Subscriber<Object>() {            @Override            public void onCompleted() {                LogUtil.i(TAG, "文字大小修改=onCompleted");            }            @Override            public void onError(Throwable throwable) {                LogUtil.i(TAG, "文字大小修改=onError");            }            @Override            public void onNext(Object o) {                LogUtil.i(TAG, "文字大小修改=onNext");            }        });    }

RxJava1使用

compile 'io.reactivex:rxjava:1.2.3'

最基本的用法如下：

 Observable.from(names).subscribe(new Action1<String>() {        @Override        public void call(String s) {            System.out.println("Hello " + s + "!");        }    });

切换线程，示例代码来自这里
有了Rxjava，我们可以跟 new Thread 和 Handler 说byebye了

Observable.empty()          .doOnCompleted(new Action0() {            @Override            public void call() {                Log.i("debug", Thread.currentThread().getName());            }        })        .subscribeOn(Schedulers.io())        .observeOn(AndroidSchedulers.mainThread())        .doOnCompleted(new Action0() {            @Override            public void call() {                Log.i("debug", Thread.currentThread().getName());            }        })        .subscribe();

RxJava2使用

这里有Rxjava2和Rxjava1的不同，https://github.com/ReactiveX/RxJava/wiki/What’s-different-in-2.0

http://search.maven.org/#search%7Cga%7C1%7Cio.reactivex.rxjava

    compile 'io.reactivex.rxjava2:rxandroid:2.0.1'    compile 'io.reactivex.rxjava2:rxjava:2.0.1'

在build.gradle里加了上面两行依赖后，直接运行就报错如下：

简直不知所措，换成另一个项目就正常了（苦笑ing），然后我试了试如下代码：

        Observable.just("哈哈，我在地球上")                .map(new Function<String, Object>() {                    @Override                    public Object apply(String s) throws Exception {                        return s + "AA";                    }                })                .subscribe(new Consumer<Object>() {                    @Override                    public void accept(Object o) throws Exception {                        LogUtil.i("TAG", "ZZZ=" + o.toString());                    }                });

使用了map操作符，打印那段文字加上AA后缀