Android——使用网络技术之使用OkHttp

首先在github上寻找okhttp依赖

我们首先创建一个OkHttpClient实例

OkHttpClient client = new OkHttpClient();

接下来如果想发起一条HTTP请求，就需要创建一个Request对象

Request request = new Request.Builder().build();

我们要在build()方法之间连缀很多其他方法来丰富这个Requset对象，比如可以通过url()方法来设置目标网络地址

 Request request = new Request.Builder()
 .url("https://www.baidu.com")
 .build();

之后调用OkHttpClient的newCall()方法来创建一个Call对象，并调用他的execute()方法来发送请求并获取服务器返回的数据

Response response = client.newCall(request).execute();

其中Response对象就是服务器返回的数据了，我们可以通过如下写法来得到返回的具体内容

 String responseData = response.body().string();

发起POST请求需要先构建出一个RequestBody对象来存放待提交的参数，

        RequestBody requestBody = new FormBody.Builder()
                .add("username","admin")
                .add("password","123456")
                .build();

然后再Request.Bulider中调用一下post()方法，并将RequestBody对象传入

        Request request1 = new Request.Builder()
                .url("https://www.baidu.com")
                .post(requestBody)
                .build();

eg:

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    TextView responseText;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button sendRequest = findViewById(R.id.send_request);
        responseText= findViewById(R.id.response_text);
        sendRequest.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        if (v.getId()==R.id.send_request){
            sendRequestWithOkHttp();
        }
    }
    private void sendRequestWithOkHttp(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                   OkHttpClient client = new OkHttpClient();
                   Request request = new Request.Builder()
                           .url("https://www.baidu.com")
                           .build();
                   Response response = client.newCall(request).execute();
                   String responseData = response.body().string();
                   showResponse(responseData);
                }catch (Exception e){
                    e.printStackTrace();
                }
            }
        }).start();
    }
    private void showResponse(final String response){
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                responseText.setText(response);
            }
        });
    }
}