Android开发之HttpClient初步

//activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >

<Button
android:id="@+id/buttonId"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="向服务器发送数据" />

</RelativeLayout>

//MainActivity.java
package com.example.http1;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
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 org.apache.http.message.BufferedHeader;
import org.xml.sax.InputSource;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private  Button button;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button = (Button)findViewById(R.id.buttonId);
button.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
//原则：在主线程中不可以访问网络
NetworkThread nt=new NetworkThread();
nt.start();
}
});
}
class NetworkThread extends Thread{
public void run(){
//创建HttpClietn对象
HttpClient httpClient = new DefaultHttpClient();
//创建代表请求的对象，参数是访问的服务器地址
HttpGet httpGet = new HttpGet("http://www.marschen.com/data1.html");
//执行请求，获取服务器发还的响应对象
try {
HttpResponse resp=httpClient.execute(httpGet);
int code = resp.getStatusLine().getStatusCode();
//检查状态码的值是否正常，检查状态码的值是否等于200
if (code==200) {
//从响应中取出数据
HttpEntity entity = resp.getEntity();
InputStream in = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line=reader.readLine();
Log.d("HTTP","从服务器取得的数据为："+line);
}
} catch (Exception e) {
e.printStackTrace();
}

}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

}

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