Android访问网络

时间:2023-12-25 18:23:19

  Android中访问网络用的是HttpClient的方式,即Apache提供的一个jar包。安卓中继承了改jar包,所以安卓adt中不需要专门import该jar,直接就可以使用。

以下是MainActivity.java代码:

package com.wyl.httptest2;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader; import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient; import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText; public class MainActivity extends ActionBarActivity {
Button btn;
EditText et; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button)findViewById(R.id.btnId);
MyOnclickListener l = new MyOnclickListener();
et = (EditText)findViewById(R.id.editTextId);
btn.setOnClickListener(l);//绑定监听器
} class MyOnclickListener implements OnClickListener{
@Override
public void onClick(View v) {
//原则:UI中的主线程不能够直接访问网络
System.out.println("====线程名:"+Thread.currentThread().getName());
getInternetThread myThread = new getInternetThread();
myThread.start(); } } class getInternetThread extends Thread{
String line = "我是空";
@Override
public void run() { System.out.println("线程名:"+Thread.currentThread().getName());
//获取EditText 控件里的 uri
String uri = et.getText().toString();
System.out.println("uri的值:"+uri);
//访问网络
//获取客户端对象
HttpClient client = new DefaultHttpClient();
//获取请求对象,并传入uri
HttpGet get = new HttpGet(uri);
//客户端发送请求对象
try {
HttpResponse resp = client.execute(get);
//获取状态码,如果是200说明成功
int code = resp.getStatusLine().getStatusCode();
if(code == 200){
//获得返回值
InputStream in = resp.getEntity().getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
line = reader.readLine();
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
et.setText(line);//设置EditText的值,这个地方会导致程序的崩溃,猜测是workThread不能够直接修改主线程即安卓UI中的数据。 } }
}

  安卓的页面如下:

Android访问网络