RxJava2 封装主要变化
- Transformer的变化:RxJava1.X为rx.Observable.Transformer接口, 继承自Func1
, Observable >, RxJava2.X为io.reactivex.ObservableTransformer ,是一个独立的接口。 - Flowable则是FlowableTransformer,如果你使用Flowable,以下ObservableTransformer替换FlowableTransformer即可。
gitHub 项目地址
封装方案
1、封装 Rx 线程相关
RxSchedulersHelper:
/**
* Created by weiss on 17/1/16.
*/
public class RxSchedulers {
public static ObservableTransformer io_main() {
return upstream ->
upstream.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread());
}
}
封装后:
Api.getInstance().movieService
.getGankData("Android",1)
.compose(RxSchedulers.io_main());
2、封装 处理服务器返回数据,管理 RxJava生命周期
HttpResult:
/**
* Created by Weiss on 2017/1/11.
*/
public class HttpResult implements Serializable {
public String code;
public String msg;
public boolean hasmore;
public T data;
public static String SUCCESS = "000";
public static String SIGN_OUT = "101";//token验证失败
public static String SHOWTOAST = "102";//显示Toast
public boolean isSuccess() {
return SUCCESS.equals(code);
}
public boolean isTokenInvalid() {
return SIGN_OUT.equals(code);
}
public boolean isShowToast() {
return SHOWTOAST.equals(code);
}
public boolean hasMore() {
return hasmore;
}
}
BaseRxActivity:
/**
* 管理RxJava生命周期,避免内存泄漏
* RxJava处理服务器返回
*
* Created by Weiss on 2016/12/23.
*/
public abstract class BaseRxActivity extends BaseActivity {
private CompositeDisposable disposables2Stop;// 管理Stop取消订阅者者
private CompositeDisposable disposables2Destroy;// 管理Destroy取消订阅者者
protected abstract int getLayoutId();
protected abstract void initView();
/**
* Rx优雅处理服务器返回
*
* @param
* @return
*/
public ObservableTransformer, T> handleResult() {
return upstream ->{
return upstream.flatMap(result -> {
if (result.isSuccess()) {
return createData(result.data);
} else if (result.isTokenInvalid()) {
//处理token失效,tokenInvalid方法在BaseActivity 实现
tokenInvalid();
} else {
return Observable.error(new Exception(result.msg));
}
return Observable.empty();
}
);
};
}
private Observable createData(final T t) {
return Observable.create(subscriber -> {
try {
subscriber.onNext(t);
subscriber.onComplete();
} catch (Exception e) {
subscriber.onError(e);
}
});
}
public boolean addRxStop(Disposable disposable) {
if (disposables2Stop == null) {
throw new IllegalStateException(
"addUtilStop should be called between onStart and onStop");
}
disposables2Stop.add(disposable);
return true;
}
public boolean addRxDestroy(Disposable disposable) {
if (disposables2Destroy == null) {
throw new IllegalStateException(
"addUtilDestroy should be called between onCreate and onDestroy");
}
disposables2Destroy.add(disposable);
return true;
}
public void remove(Disposable disposable) {
if (disposables2Stop == null && disposables2Destroy == null) {
throw new IllegalStateException("remove should not be called after onDestroy");
}
if (disposables2Stop != null) {
disposables2Stop.remove(disposable);
}
if (disposables2Destroy != null) {
disposables2Destroy.remove(disposable);
}
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (disposables2Destroy != null) {
throw new IllegalStateException("onCreate called multiple times");
}
disposables2Destroy = new CompositeDisposable();
}
public void onStart() {
super.onStart();
if (disposables2Stop != null) {
throw new IllegalStateException("onStart called multiple times");
}
disposables2Stop = new CompositeDisposable();
}
public void onStop() {
super.onStop();
if (disposables2Stop == null) {
throw new IllegalStateException("onStop called multiple times or onStart not called");
}
disposables2Stop.dispose();
disposables2Stop = null;
}
public void onDestroy() {
super.onDestroy();
if (disposables2Destroy == null) {
throw new IllegalStateException(
"onDestroy called multiple times or onCreate not called");
}
disposables2Destroy.dispose();
disposables2Destroy = null;
}
}
封装后 (BaseRxActivity的子类使用):
addRxDestroy(Api.getInstance().movieService
.getGankData("Android",1)
.compose(RxSchedulers.io_main())
.compose(handleResult())
.省略
);
handleResult为什么不新建一个类处理呢?因为很多异常处理需要context对象,或者和BaseActivity有千丝万缕的联系,BaseRxActivity继承BaseActivity可以很简洁优雅处理各种异常。比如token失效,是需要跳转到登录页面的。在新建一个类中,不能持有context对象,只能使用Application的Context,同时方便与Activity通信交互满足各种需求。BaseRxActivity还可以管理RxJava生命周期。
3、异常处理
/**
* Created by Weiss on 2017/2/9.
*/
public class RxException implements Consumer {
private static final String TAG = "RxException";
private static final String SOCKETTIMEOUTEXCEPTION = "网络连接超时,请检查您的网络状态,稍后重试";
private static final String CONNECTEXCEPTION = "网络连接异常,请检查您的网络状态";
private static final String UNKNOWNHOSTEXCEPTION = "网络异常,请检查您的网络状态";
private Consumer super Throwable> onError;
public RxException(Consumer super Throwable> onError) {
this.onError=onError;
}
/**
* Consume the given value.
*
* @param t the value
* @throws Exception on error
*/
@Override
public void accept(T t) throws Exception {
if (t instanceof SocketTimeoutException) {
Log.e(TAG, "onError: SocketTimeoutException----" + SOCKETTIMEOUTEXCEPTION);
ToastUtils.show(SOCKETTIMEOUTEXCEPTION);
onError.accept(new Throwable(SOCKETTIMEOUTEXCEPTION));
} else if (t instanceof ConnectException) {
Log.e(TAG, "onError: ConnectException-----" + CONNECTEXCEPTION);
ToastUtils.show(CONNECTEXCEPTION);
onError.accept(new Throwable(CONNECTEXCEPTION));
} else if (t instanceof UnknownHostException) {
Log.e(TAG, "onError: UnknownHostException-----" + UNKNOWNHOSTEXCEPTION);
ToastUtils.show(UNKNOWNHOSTEXCEPTION);
onError.accept(new Throwable(UNKNOWNHOSTEXCEPTION));
} else {
Log.e(TAG, "onError:----" + t.getMessage());
onError.accept(t);
}
}
}
封装后 (BaseRxActivity的子类使用):
addRxDestroy(Api.getInstance().movieService
.getGankData("Android",1)
.compose(RxSchedulers.io_main())
.compose(handleResult())
.subscribe(httpResult -> adapter.setItems(data),
new RxException<>(e ->e.printStackTrace()))
);
4、多页请求封装
实体类:
/**
* Created by Weiss on 2017/1/20.
*/
public class Gank extends BaseListEntity {
@Override
public Observable>> getPage(int page) {
return GankApi.getInstance().service.getGankData(param.get("gank"), page)
.compose(RxSchedulers.io_main());
}
}
实体类继承 BaseListEntity,实现getPage方法即可。
UI视图:
public class MainActivityFragment extends BaseRxFragment {
@BindView(R.id.ptrRecyclerView)
PtrRecyclerView ptrRecyclerView;
private MultiTypeAdapter adapter;
public MainActivityFragment() {
}
@Override
protected int getLayoutId() {
return R.layout.fragment_main;
}
@Override
protected void initView() {
ptrRecyclerView.setParam("gank","Android");
adapter = new MultiTypeAdapter();
adapter.register(Gank.class,new GankViewProvider());
ptrRecyclerView.setAdapter(adapter,new Gank());
}
}
只需要写一个适配器和实体类,轻松实现多页请求,PtrRecyclerView下拉刷新和上拉加载是会自动调用getPage()方法获取数据。
PtrRecyclerView目前只是简单实现下拉刷新和上拉加载,有空会完善,当然例子也会完善。当然PtrRecyclerView的封装会根据RecyclerView原生的方法名参数,减少学习成本。
后记
还可以封装网络加载对话框,这个看个人喜好,同样以上封装同样可以看个人喜好和项目需求自由组装。
RxJava2 + Retrofit2 封装 giithub 源码地址
相关链接
RxJava 2.0有什么不同(译)
探索专为 Android 而设计的 RxJava 2
RxJava2 + Retrofit2 开发框架