public class PhoneAddress {private boolean success;private String tel;private Info info;public static class Info{private String local;private String duan;private String type;private String yys;private String bz;@Overridepublic String toString() {return "Info{" +"local='" + local + '\'' +", duan='" + duan + '\'' +", type='" + type + '\'' +", yys='" + yys + '\'' +", bz='" + bz + '\'' +'}';}}public void show(){System.out.println(success);System.out.println(tel);System.out.println(info.local);System.out.println(info.duan);System.out.println(info.type);System.out.println(info.yys);System.out.println(info.bz);}@Overridepublic String toString() {return "PhoneAddress{" +"success=" + success +", tel='" + tel + '\'' +", info=" + info +'}';}
}

        4 创建用于描述网络请求的接口

public interface GetRequest_Interface {@GET("api/phone?")Call<PhoneAddress> getCall(@Query("tel")String tel);
}

5 创建Retrofit实例

        6 创建网络请求接口实例

        7 发送网络请求

        8 处理返回结果

//创建Retrofit对象
Retrofit retrofit=new Retrofit.Builder().baseUrl("https://api.vvhan.com/").addConverterFactory(GsonConverterFactory.create()).build();
//创建网络请求接口的实例
GetRequest_Interface request=retrofit.create(GetRequest_Interface.class);
//对发送送请求进行封装
Call<PhoneAddress> call=request.getCall(phonenum);
//发送网络请求(异步)
call.enqueue(new Callback<PhoneAddress>() {@Overridepublic void onResponse(Call<PhoneAddress> call, Response<PhoneAddress> response) {tv_show.setText(response.body().toString());}@Overridepublic void onFailure(Call<PhoneAddress> call, Throwable t) {Log.i("onFailure","请求失败");}
});

４ Retrofit的使用（异步POST）

       1 添加Retrofit库的依赖  

implementation("com.squareup.okhttp3:okhttp:4.10.0")
implementation 'com.squareup.retrofit2:retrofit:2.4.0'
implementation 'com.squareup.retrofit2:converter-gson:2.0.2'

2 添加网络权限

<uses-permission android:name="android.permission.INTERNET"/>

        3 创建接收服务器返回数据的类

public class LoginInfo {private int success;private String info;@Overridepublic String toString() {return "LoginInfo{" +"success=" + success +", info='" + info + '\'' +'}';}
}

4 创建用于描述网络请求的接口 （接收请求体）

public interface PostRequest_Interface {@POST("login")Call<LoginInfo> postCall(@Body RequestBody requestBody);
}

5 创建Retrofit实例

        6 创建网络请求接口实例

        7 发送网络请求

        8 处理返回结果

 private void postData(String num) {Retrofit retrofit=new Retrofit.Builder().baseUrl("http://192.168.17.181:8080/TestWeb_war_exploded/").addConverterFactory(GsonConverterFactory.create()).build();PostRequest_Interface request=retrofit.create(PostRequest_Interface.class);MediaType type=MediaType.Companion.parse("application/json;charset=utf-8");RequestBody body=RequestBody.Companion.create(num,type);Call<LoginInfo> call=request.postCall(body);call.enqueue(new Callback<LoginInfo>() {@Overridepublic void onResponse(Call<LoginInfo> call, Response<LoginInfo> response) {Log.i("onResponse",response.body().toString());}@Overridepublic void onFailure(Call<LoginInfo> call, Throwable t) {Log.i("onFailure","失败");}});}

５Retrofit+OkHTTP+RecycleView的实现步骤

第一步： 创建项目

第二步：导入依赖

implementation "com.github.bumptech.glide:glide:4.12.0" implementation("com.squareup.okhttp3:okhttp:4.10.0") implementation 'com.squareup.retrofit2:retrofit:2.4.0' implementation 'com.squareup.retrofit2:converter-gson:2.0.2'

第三步：添加网络权限

<uses-permission android:name="android.permission.INTERNET" />

第四步：在activity_main.xml添加Recycle，并给其设置id

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"tools:context=".MainActivity"android:orientation="vertical"android:padding="5dp"><androidx.recyclerview.widget.RecyclerViewandroid:id="@+id/rv_news"android:layout_width="match_parent"android:layout_height="match_parent" />
</LinearLayout>

第五步：创建子布局 news_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="200dp"android:orientation="vertical"xmlns:app="http://schemas.android.com/apk/res-auto"app:cardCornerRadius="5dp"android:padding="5dp"app:cardElevation="5dp"><LinearLayoutandroid:layout_width="match_parent"android:layout_height="190dp"android:layout_margin="5dp"android:orientation="horizontal"><ImageViewandroid:id="@+id/news_show"android:layout_width="190dp"android:layout_height="190dp"app:srcCompat="@drawable/ic_launcher_background" /><LinearLayoutandroid:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><TextViewandroid:layout_marginTop="5dp"android:id="@+id/news_title"android:layout_marginStart="10dp"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="TextView" /><TextViewandroid:layout_marginTop="20dp"android:id="@+id/news_desc"android:layout_marginStart="10dp"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="TextView" /></LinearLayout></LinearLayout>
</androidx.cardview.widget.CardView>

第六步：创建实体类

package com.hopu.day23_practice.model;import java.util.List;public class News {private boolean success;private String title;private String subtitle;private String update_time;private List<Data> data;public void setSuccess(boolean success) {this.success = success;}public boolean getSuccess() {return success;}public void setTitle(String title) {this.title = title;}public String getTitle() {return title;}public void setSubtitle(String subtitle) {this.subtitle = subtitle;}public String getSubtitle() {return subtitle;}public String getUpdate_time() {return update_time;}public void setUpdate_time(String update_time) {this.update_time = update_time;}public void setData(List<Data> data) {this.data = data;}public List<Data> getData() {return data;}public class Data {private int index;private String title;private String desc;private String pic;private String hot;private String url;private String mobilUrl;public void setIndex(int index) {this.index = index;}public int getIndex() {return index;}public void setTitle(String title) {this.title = title;}public String getTitle() {return title;}public void setDesc(String desc) {this.desc = desc;}public String getDesc() {return desc;}public void setPic(String pic) {this.pic = pic;}public String getPic() {return pic;}public void setHot(String hot) {this.hot = hot;}public String getHot() {return hot;}public void setUrl(String url) {this.url = url;}public String getUrl() {return url;}public void setMobilUrl(String mobilUrl) {this.mobilUrl = mobilUrl;}public String getMobilUrl() {return mobilUrl;}@Overridepublic String toString() {return "Data{" +"index=" + index +", title='" + title + '\'' +", desc='" + desc + '\'' +", pic='" + pic + '\'' +", hot='" + hot + '\'' +", url='" + url + '\'' +", mobilUrl='" + mobilUrl + '\'' +'}';}}@Overridepublic String toString() {return "News{" +"success=" + success +", title='" + title + '\'' +", subtitle='" + subtitle + '\'' +", update_time='" + update_time + '\'' +", data=" + data +'}';}
}

第七步：创建适配器

public class NewsAdapter extends RecyclerView.Adapter<NewsAdapter.ViewHolder> {List<News.Data> list;public void setResource(List<News.Data> list){this.list=list;notifyDataSetChanged();}@NonNull@Overridepublic ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {View view=LayoutInflater.from(parent.getContext()).inflate(R.layout.news_item,parent,false);ViewHolder viewHolder=new ViewHolder(view);return viewHolder;}@Overridepublic void onBindViewHolder(@NonNull ViewHolder holder, int position) {News.Data data=list.get(position);Glide.with(holder.view).load(data.getPic()).into(holder.news_show);holder.news_title.setText(data.getTitle());holder.news_desc.setText(data.getDesc());}@Overridepublic int getItemCount() {if (list==null){return 0;}else {return list.size();}}public class ViewHolder extends RecyclerView.ViewHolder {ImageView news_show;TextView news_title;TextView news_desc;View view;public ViewHolder(@NonNull View itemView) {super(itemView);view=itemView;news_desc=itemView.findViewById(R.id.news_desc);news_title=itemView.findViewById(R.id.news_title);news_show=itemView.findViewById(R.id.news_show);}}
}

第八步：设置适配器

    //声明容器NewsAdapter newsAdapter;RecyclerView rv_news;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);rv_news=findViewById(R.id.rv_news);newsAdapter=new NewsAdapter();LinearLayoutManager layoutManager=new LinearLayoutManager(this);rv_news.setLayoutManager(layoutManager);rv_news.setAdapter(newsAdapter);initData();}

第九步：进行网络请求

1. 创建请求接口

public interface News_Interface {@GET("api/hotlist?type=zhihuHot")Call<News> getNews();
}

private void initData() {Retrofit retrofit=new Retrofit.Builder().baseUrl("https://api.vvhan.com/").addConverterFactory(GsonConverterFactory.create()).build();News_Interface news_interface=retrofit.create(News_Interface.class);Call<News> call=news_interface.getNews();call.enqueue(new Callback<News>() {@Overridepublic void onResponse(Call<News> call, Response<News> response) {Log.i("onResponse",response.body().toString());newsAdapter.setResource(response.body().getData());}@Overridepublic void onFailure(Call<News> call, Throwable t) {Log.i("onFailure","请求失败");}});}