Retrofit + RxJava ＋ OkHttp+MVP 让网络请求变的简单
网络请求
Android中有名的网络请求库就那么几个, Retrofit能够从中脱颖而出很大原因就是因为它支持RxJava的方式来调用, 下面简单讲解一下它的基本用法.
1、要使用Retrofit,先添加Gradle配置:
compile 'io.reactivex.rxjava2:rxjava:2.2.1'
compile 'io.reactivex.rxjava2:rxandroid:2.1.0'
//retrofit
compile 'com.squareup.retrofit2:retrofit:2.3.0'
//Gson converter
compile 'com.squareup.retrofit2:converter-gson:2.3.0'
//RxJava2 Adapter
compile "com.squareup.retrofit2:adapter-rxjava2:2.3.0"
//okhttp
compile 'com.squareup.okhttp3:okhttp:3.4.1'
compile 'com.squareup.okhttp3:logging-interceptor:3.9.1'
2、随后定义Api接口,本篇采用开源天气接口
public interface ApiStores {
//baseUrl
String API_SERVER_URL = "http://www.weather.com.cn/";
//加载天气
@GET("adat/sk/{cityId}.html")
Observable<MainModel> loadDataByRetrofitRxJava(@Path("cityId") String cityId);
}
3、接着创建一个Retrofit客户端:
/**
* 创建一个Retrofit客户端:
*/
public class ApiClient {
public static Retrofit mRetrofit;
public static Retrofit retrofit() {
if (mRetrofit == null) {
OkHttpClient.Builder builder = new OkHttpClient.Builder();
builder.readTimeout(5, TimeUnit.SECONDS);
builder.connectTimeout(5, TimeUnit.SECONDS);
if (BuildConfig.DEBUG) {
// Log信息拦截器
HttpLoggingInterceptor loggingInterceptor = new HttpLoggingInterceptor();
loggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
//设置 Debug Log 模式
builder.addInterceptor(loggingInterceptor);
}
OkHttpClient okHttpClient = builder.build();
mRetrofit = new Retrofit.Builder()
.baseUrl(ApiStores.API_SERVER_URL)
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.client(okHttpClient)
.build();
}
return mRetrofit;
}
}
MainModel
/**
MainModel
*/
public class MainModel {
private WeatherinfoBean weatherinfo;
public WeatherinfoBean getWeatherinfo() {
return weatherinfo;
}
public void setWeatherinfo(WeatherinfoBean weatherinfo) {
this.weatherinfo = weatherinfo;
}
public static class WeatherinfoBean {
private String city;
private String cityid;
private String temp;
private String WD;
private String WS;
private String SD;
private String WSE;
private String time;
private String isRadar;
private String Radar;
private String njd;
private String qy;
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getCityid() {
return cityid;
}
public void setCityid(String cityid) {
this.cityid = cityid;
}
public String getTemp() {
return temp;
}
public void setTemp(String temp) {
this.temp = temp;
}
public String getWD() {
return WD;
}
public void setWD(String WD) {
this.WD = WD;
}
public String getWS() {
return WS;
}
public void setWS(String WS) {
this.WS = WS;
}
public String getSD() {
return SD;
}
public void setSD(String SD) {
this.SD = SD;
}
public String getWSE() {
return WSE;
}
public void setWSE(String WSE) {
this.WSE = WSE;
}
public String getTime() {
return time;
}
public void setTime(String time) {
this.time = time;
}
public String getIsRadar() {
return isRadar;
}
public void setIsRadar(String isRadar) {
this.isRadar = isRadar;
}
public String getRadar() {
return Radar;
}
public void setRadar(String Radar) {
this.Radar = Radar;
}
public String getNjd() {
return njd;
}
public void setNjd(String njd) {
this.njd = njd;
}
public String getQy() {
return qy;
}
public void setQy(String qy) {
this.qy = qy;
}
}
}
4、然后发起请求就很简单了:
创建上游即Observable 被观察者 然后去订阅下游观察者
ApiClient.retrofit().create(ApiStores.class).loadDataByRetrofitRxJava("101220602")
ApiClient.retrofit().create(ApiStores.class).loadDataByRetrofitRxJava("101220602")
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Observer<MainModel>() {
@Override
public void onSubscribe(Disposable d) {
}
@Override
public void onNext(MainModel mainModel) {
Log.w(TAG, "" + mainModel.getWeatherinfo().getCity());
Log.d(TAG, "observer thread is : " + Thread.currentThread().getName());
}
@Override
public void onError(Throwable e) {
Toast.makeText(MainActivity.this, "登录失败", Toast.LENGTH_SHORT).show();
}
@Override
public void onComplete() {
Toast.makeText(MainActivity.this, "登录成功", Toast.LENGTH_SHORT).show();
}
});
}
rxjava+retrofit处理网络请求
在使用rxjava+retrofit处理网络请求的时候，一般会采用对观察者进行封装，实现代码复用和拓展。
基类observer
public abstract class BaseObserver<T> implements Observer<T> {
protected String errMsg = "";
protected Disposable disposable;
@Override
public void onSubscribe(Disposable d) {
disposable = d;
}
@Override
public void onNext(T t) {}
@Override
public void onError(Throwable e) {
LogUtils.d("Subscriber onError", e.getMessage());
if (!NetworkUtils.isConnected()) {
errMsg = "网络连接出错,";
} else if (e instanceof APIException) {
APIException exception = (APIException) e;
errMsg = exception.getMessage() + ", ";
} else if (e instanceof HttpException) {
errMsg = "网络请求出错,";
} else if (e instanceof IOException) {
errMsg = "网络出错,";
}
if (disposable != null && !disposable.isDisposed()) {
disposable.dispose();
}
}
@Override
public void onComplete() {
if (disposable != null && !disposable.isDisposed()) {
disposable.dispose();
}
}
}
内存泄露处理
基本代码：
使用observer 或者Subscriber 创建观察者
private final CompositeDisposable disposables = new CompositeDisposable();
// 1. 创建一个普通的 observable
Observable<String> observable = Observable.create(new ObservableOnSubscribe<String>() {
@Override
public void subscribe(ObservableEmitter<String> e) throws Exception {
if (e.isDisposed()) return;
SystemClock.sleep(2000);
e.onNext("next");
e.onComplete();
}
});
// 2. 创建一个可被 CompositeDisposable 管理的 observer
DisposableObserver<String> observer = new DisposableObserver<String>() {
@Override
public void onNext(String value) {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onComplete() {
}
};
// 3. 订阅事件
observable.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(observer);
// 4. 将需要被 CompositeDisposable 管理的 observer 加入到管理集合中
disposables.add(observer);
}
在 Activity／Fragment 销毁生命周期中取消异步操作防止内存泄露：
@Override
protected void onDestroy() {
super.onDestroy();
// 将所有的 observer 取消订阅
disposables.clear();
}
