Retrofit使用

//依赖  权限

//compile 'com.squareup.retrofit2:retrofit:2.0.0'

//compile 'com.squareup.retrofit2:converter-gson:2.0.2'

//Main

package com.example.myretrofit;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import okhttp3.ResponseBody;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;

public class MainActivity extends AppCompatActivity {

    private TextView ll;
    private Call<ResponseBody> call;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView qs = (TextView) findViewById(R.id.qs);
        Button viewById = (Button) findViewById(R.id.xuanfu);
        viewById.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                 Intent intent = new Intent(MainActivity.this,Main3Activity.class);
                                     startActivity(intent);
            }
        });
        qs.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                 Intent intent = new Intent(MainActivity.this,Main2Activity.class);
                                     startActivity(intent);
            }
        });
        ll = (TextView) findViewById(R.id.ll);
        initReteofit();
    }

    private void initReteofit() {
        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(Constant.URL_BASE)
                .build();

        RetrofitService retrofitService = retrofit.create(RetrofitService.class);
        call = retrofitService.getLatestJsonString();
        // 用法和OkHttp的call如出一辙,
        // 不同的是如果是Android系统回调方法执行在主线程
        call.enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {

                //对返回结果做成功与内容的判断
                if (response.isSuccessful() && response.body() != null) {
                    try {
                        //得到结果
                        String string = response.body().string();
                        Log.e("chen", "onResponse: "+string );
                        //更新UI
                        ll.setText(string);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
            @Override
            public void onFailure(Call<ResponseBody> call, Throwable t) {
//                t.printStackTrace();
                Log.e("chen", "onFailure: "+"加载失败" );
            }
        });
    }
    //为节约资源,当屏幕不可见时,我们停止网络请求
    @Override
    protected void onStop() {
        super.onStop();
        if (call != null) {
            call.cancel();
        }
    }

}

//main布局

<?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"
    android:orientation="vertical"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" tools:context="com.example.myretrofit.MainActivity">
   <TextView
       android:text="dxjfbv"
       android:textSize="25dp"
       android:layout_width="wrap_content"
       android:layout_height="30dp"
       android:id="@+id/ll"/>
   <Button
       android:id="@+id/qs"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:text="点击我给你看糗事段子"/>

   <Button
       android:id="@+id/xuanfu"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:text="跳转到炫富列车"/>

</LinearLayout>

//RetrofitService接口

package com.example.myretrofit;

import okhttp3.ResponseBody;
import retrofit2.Call;
import retrofit2.http.GET;
import retrofit2.http.POST;

public interface RetrofitService {
    //请求方式为GET，参数为basil2style，因为没有变量所以下面getString方法也不需要参数
    @GET("article/list/latest?page=1")
    //定义返回的方法，返回的响应体使用了ResponseBody
    Call<ResponseBody> getLatestJsonString();

    @POST("")
    Call<ResponseBody> chen();
}