添加权限
首先要在manifest中加上访问网络的权限：
复制代码 代码如下:
<manifest ... >
<uses-permission android:name="android.permission.INTERNET" />
...
</manifest>

完整的Manifest文件如下：
复制代码 代码如下:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.httpdemo1"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.httpdemo1.HttpDemo1Activity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

布局代码如下：
复制代码 代码如下:
<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=".HttpDemo1Activity" >
<TextView
android:id="@+id/myWebTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
<Button
android:id="@+id/requestBtn"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="Send Request" />
<WebView
android:id="@+id/webview"
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:layout_above="@id/requestBtn"
android:layout_below="@id/myWebTitle" />
</RelativeLayout>
activity_http_demo1.xml

主要的代码：
复制代码 代码如下:
package com.example.httpdemo1;
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.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.webkit.WebView;
import android.widget.Button;
public class HttpDemo1Activity extends Activity
{
private Button mSendReqBtn = null;// 发送请求的按钮
private WebView mWebView = null;// 用于显示结果，用载入html字符串的方式显示响应结果，而不是使用WebView自己的方式加载URL
// 响应
private HttpResponse mHttpResponse = null;
// 实体
private HttpEntity mHttpEntity = null;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_http_demo1);
mSendReqBtn = (Button) findViewById(R.id.requestBtn);
mSendReqBtn.setOnClickListener(mSendClickListener);
mWebView = (WebView) findViewById(R.id.webview);
}
private OnClickListener mSendClickListener = new OnClickListener()
{
@Override
public void onClick(View v)
{
// 生成一个请求对象
HttpGet httpGet = new HttpGet("http:///reference/org/apache/http/package-summary.html