引用第三方进行Android前端与web后台的数据交互

1.首先你需要导入jar包，如图：

2.然后把jar包放入Project(Android)

3.注意：useLibrary 'org.apache.http.legacy'这句话需要放入Project你所在的项目里的gradle,版本处。看图：

4.web后台服务做一个简易的登录页面

演示代码：

loginServlet

package com.ZGL.servlet;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class LoginServlet extends HttpServlet{@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//获取用户名和密码String uname=req.getParameter("uname");String upass=req.getParameter("upass");System.out.println(uname+" "+upass);String result=null;//判断if("admin".equals(uname)&&"123".equals(upass)){result="success";}else{result="fail";}PrintWriter pw=resp.getWriter();pw.write(result);pw.close();}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doPost(req, resp);}}

还需要xml配置

5.Android前端代码演示：

布局：

Activity:

public class MainActivity extends AppCompatActivity {    private EditText et_main_uname;    private EditText et_main_upass;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        et_main_uname = (EditText) findViewById(R.id.et_main_uname);        et_main_upass = (EditText) findViewById(R.id.et_main_upass);    }    public  void  loginAsyncHttpClient(View v){        String uname=et_main_uname.getText().toString();        String upass=et_main_upass.getText().toString();        String path="http://192.168.43.238:8080/Myweb_01/login.do";        AsyncHttpClient ahc=new AsyncHttpClient();        RequestParams p=new RequestParams();        p.put("uname",uname);        p.put("upass",upass);        ahc.post(this,path,p,new TextHttpResponseHandler(){            @Override            public void onFailure(int statusCode, Header[] headers, String responseBody, Throwable error) {                super.onFailure(statusCode, headers, responseBody, error);            }            @Override            public void onSuccess(int statusCode, Header[] headers, String responseBody) {                super.onSuccess(statusCode, headers, responseBody);                Toast.makeText(MainActivity.this, responseBody, Toast.LENGTH_SHORT).show();            }        });    }

xml:网络权限配置：

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