Android-多列表的项目（Rxjava+Rtrofit+Recyclerview+Glide+Adapter封装）之（二）网络层的封装

接着来，本系列的第二篇，就是重中之重啦，网络层的封装。第一篇是：Android-多列表的项目（Rxjava+Rtrofit+Recyclerview+Glide+Adapter封装）之（一）项目架构

本文章结构：1.网络层封装涉及的东西；2.如何封装网络层；3.如何使用封装了的网络层。

一、网络层封装涉及的东西

大众方案：OkHttp+Rxjava+Rtrofit

介绍： Retrofit和okHttp师出同门，也是Square的开源库，它是一个类型安全的网络请求库，Retrofit简化了网络请求流程，基于OkHtttp做了封装，解耦的更彻底:比方说通过注解来配置请求参数，通过工厂来生成CallAdapter，Converter，你可以使用不同的请求适配器(CallAdapter), 比方说RxJava，Java8, Guava。你可以使用不同的反序列化工具(Converter)，比方说json, protobuff, xml, moshi等等。

二、如何封装网络层

1.导入

// https://github.com/ReactiveX/RxAndroid rx异步
compile 'io.reactivex:rxandroid:1.2.1'
compile 'io.reactivex:rxjava:1.1.6'
// https://github.com/square/retrofit  网络请求
compile 'com.squareup.retrofit2:retrofit:2.1.0'
compile 'com.squareup.retrofit2:converter-gson:2.1.0'
compile 'com.squareup.retrofit2:adapter-rxjava:2.1.0'
//https://github.com/franmontiel/PersistentCookieJar Okhttp的Cookie缓存
compile 'com.github.franmontiel:PersistentCookieJar:v1.0.0'

2.RetrofitUtil实现Retrofit单例：

public class RetrofitUtil {
private static final String TAG = "retrofit";
//TODO:修改主机地址
private static final String BASE_URL = "https://api.douban.com";
private static final int DEFAULT_TIMEOUT = 5;
private static Retrofit retrofit;

//实例化私有
private RetrofitUtil(){

}
//单例Retrofit
public static Retrofit getInstance(){
if(retrofit==null) {
//这里有个很关键的地方，就是传入App的上下文啦。
ClearableCookieJar cookieJar =
new PersistentCookieJar(new SetCookieCache(), new SharedPrefsCookiePersistor(App.getInstance()));
OkHttpClient.Builder httpClientBuilder = new OkHttpClient.Builder();                //okhttp创建，写入缓存机制，还有addInterceptor
httpClientBuilder.connectTimeout(DEFAULT_TIMEOUT, TimeUnit.SECONDS);
File cacheFile = new File(App.getInstance().getCacheDir(), "superman");
Cache cache = new Cache(cacheFile, 1024 * 1024 * 100); //100Mb。这里开始就是缓存设置啦。实现一键缓存以及请求头的配置等等
httpClientBuilder.cache(cache);
httpClientBuilder.cookieJar(cookieJar);
httpClientBuilder.addInterceptor(LoggingInterceptor);
httpClientBuilder.addInterceptor(REWRITE_CACHE_CONTROL_INTERCEPTOR);
httpClientBuilder.addNetworkInterceptor(REWRITE_CACHE_CONTROL_INTERCEPTOR);

return new Retrofit.Builder()                          //retrofit的创建。
.client(httpClientBuilder.build())          //传入okhttp
.addConverterFactory(GsonConverterFactory.create())             //传入gson解析手段
.addCallAdapterFactory(RxJavaCallAdapterFactory.create())           //传入异步手段
.baseUrl(BASE_URL)              //传入服务器地址
.build();
}else{
return retrofit;
}
}
//okHttp的拦截器
private static final Interceptor LoggingInterceptor = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
long t1 = System.nanoTime();
Logger.t(TAG).i(String.format("Sending request %s on %s%n%s", request.url(),  chain.connection(), request.headers()));
Response response = chain.proceed(request);
long t2 = System.nanoTime();
Logger.t(TAG).i(String.format("Received response for %s in %.1fms%n%s", response.request().url(), (t2 - t1) / 1e6d, response.headers()));
return response;
}
};
//okHttp的拦截器
private static final Interceptor REWRITE_CACHE_CONTROL_INTERCEPTOR = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
if(!NetUtil.isConnected(App.getInstance())){//判断是否有网络再进行操作
request = request.newBuilder()
.cacheControl(CacheControl.FORCE_CACHE)
.build();
Logger.t(TAG).w("no network");
}
//请求头缓存控制
Response originalResponse = chain.proceed(request);
if(NetUtil.isConnected(App.getInstance())){
//有网的时候读接口上的@Headers里的配置，你可以在这里进行统一的设置
String cacheControl = request.cacheControl().toString();
return originalResponse.newBuilder()
.header("Cache-Control", cacheControl)
.removeHeader("Pragma")
.build();
}else{
return originalResponse.newBuilder()
.header("Cache-Control", "public, only-if-cached, max-stale=2419200")
.removeHeader("Pragma")
.build();
}
}
};
}

3.调用前关键配置：

一个app的类获取app的上下文，以及其关键配置

public class App extends Application {

private static App app;
@Override
protected void attachBaseContext(Context base) {
super.attachBaseContext(base);
}
@Override
public void onCreate() {
super.onCreate();
MultiDex.install(this);
app = this;
}
public static App getInstance() {
return app;
}
}

//这里关键是要注册这个app的上下文
<application
android:name=".App"  //也就是这里啦
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:allowBackup="true"
android:theme="@style/AppTheme">
<activity android:name=".activity.MainActivity"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

三、如何使用封装的网络层：

1.输入主机地址，编写接口：

public interface MovieRequest {
//    //请求参数，注意这个接口要跟bean完全对应，根据第二点来操作就对了
@GET("/v2/movie/top250")
Observable<AbilityBean> getMovies(@Query("start") int start, @Query("count") int count);
}

2.使用postman等工具先查看那个数据，json。然后使用gsonformat，生成那个bean。GsonFormat的使用

package com.fuzhucheng.rxjavartrofitrecyclerview.bean;

import java.util.List;

/**
* Created by 符柱成 on 2016/12/14.
*/
public class AbilityBean {

public int image;
public String place;
public int like;
public int price;

public int count;
public int start;
public int total;
public String title;
public List<SubjectsEntity> subjects;

public AbilityBean(int image, String place, int like, int price) {
this.image = image;
this.place = place;
this.like = like;
this.price = price;
}

public static class SubjectsEntity {

public RatingEntity rating;
public String title;
public int collect_count;
public String original_title;
public String subtype;
public String year;
public RatingEntity.ImagesEntity images;
public String alt;
public String id;
public List<String> genres;
public List<RatingEntity.CastsEntity> casts;
public List<RatingEntity.DirectorsEntity> directors;

public static class RatingEntity {

public int max;
public double average;
public String stars;
public int min;

public static class ImagesEntity {

public String small;
public String large;
public String medium;

}

public static class CastsEntity {

public String alt;
public AvatarsEntity avatars;
public String name;
public String id;

public static class AvatarsEntity {

public String small;
public String large;
public String medium;

}
}

public static class DirectorsEntity {

public String alt;
public AvatarsEntityX avatars;
public String name;
public String id;

public static class AvatarsEntityX {

public String small;
public String large;
public String medium;

}
}
}
}
}

3.但是呢我们经常看到一个这么大的json，有些数据我们是不会用到的嘛，所以我们可以写多一个bean去对应我们的客户端嘛。

如果我们的客户端一个列表只需这么多信息，那就写个这么小的bean就足够了嘛。

public class AbilityItem {
private String image;
private String title;
private String content;

public String getImage() {
return image;
}

public void setImage(String image) {
this.image = image;
}

public String getTitle() {
return title;
}

public void setTitle(String title) {
this.title = title;
}

public String getContent() {
return content;
}

public void setContent(String content) {
this.content = content;
}

public AbilityItem(String image, String title, String content) {
this.image = image;
this.title = title;
this.content = content;
}
}

4.使用

private List<AbilityItem> datas = new ArrayList<>();//为列表保存bean
private CommonAdapter<AbilityItem> adapter;//列表的适配器
private MovieRequest movieRequest;//请求的接口

//这个方法放进loadData加载即可
private void getMovie() {
movieRequest = RetrofitUtil.getInstance().create(MovieRequest.class);//使用我们的工具类，反射得到请求体
//下面是rxjava的格式啦
movieRequest.getMovies(0, 10)
.subscribeOn(Schedulers.io())
.unsubscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Subscriber<AbilityBean>() {
@Override
public void onCompleted() {

}

@Override
public void onError(Throwable e) {
ToastUtils.showToast(getActivity(), getString(R.string.request_error));
}

@Override
public void onNext(AbilityBean abilityBean) {
swipeRefreshLayout.setRefreshing(false);//这个是下拉刷新的
datas.clear();//避免数据重复，清楚数据
ToastUtils.showToast(getActivity(), getString(R.string.request_success));
for (int i = 0; i < abilityBean.subjects.size(); i++) {
datas.add(new AbilityItem(abilityBean.subjects.get(i).images.medium, abilityBean.subjects.get(i).title, abilityBean.subjects.get(i).year));//列表的数据
bitmapList.add(abilityBean.subjects.get(i).images.large);//那个轮播图的数据
}
loadConvenientBanner();//从父类继承得来的方法
//下面是设置适配器，对应view与数据
adapter = new CommonAdapter<AbilityItem>(getActivity(), R.layout.item_fragment_ability_recyclerview, datas) {
@Override
protected void convert(ViewHolder holder, final AbilityItem abilityItem, final int position) {
//使用这个封装好的adapter模式去设置好一系列的view，与数据对应上
holder.setText(R.id.place, abilityItem.getTitle());
holder.setText(R.id.price, abilityItem.getContent());
ImageView circleImageView = holder.getView(R.id.image);
Glide.with(getActivity()).load(abilityItem.getImage()).into(circleImageView);
}
};
recyclerView.setAdapter(adapter);
}
});
}

其中的一个调试原理：Rtrofit做好的封装是：1.请求不成功执行onError；2.请求成功，但是onNext解析过程出现错误，同样执行onError。

源码下载：Android-多列表的项目Rxjava+Rtrofit+Recyclerview+Glide+Adapter封装

好了，Android-多列表的项目（Rxjava+Rtrofit+Recyclerview+Glide+Adapter封装）之（二）网络层的封装讲完了。本博客是这个系列的第二篇，所以讲得是网络层的封装。另外，这个系列还有一些我在外包项目过程中做的优化，以及一些发布签名等等技巧，我会尽快出完给大家，分享经验给大家。欢迎在下面指出错误，共同学习！！你的点赞是对我最好的支持！！

更多内容，可以访问JackFrost的博客