Android学习笔记---24_网络通信之网页源码查看器
24_网络通信之网页源码查看器
2013-03-18
24_网络通信之网页源码查看器
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1.界面：一个输入text框，输入一个网页的地址，点击查看后，再下面的<TextView>控件
显示，如果内容较多，需要显示滚动条。
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2.Http watch可以用这个工具来查看http协议封装的信息。
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2013-03-19
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3.从internet获取数据的相关知识：
从Internet获取数据
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利用HttpURLConnection对象,我们可以从网络中获取网页数据.
URL url = new URL(" http://www.sohu.com");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5* 1000);//设置连接超时
conn.setRequestMethod(“GET”);//以get方式发起请求
if (conn.getResponseCode() != 200) throw new RuntimeException("请求url失败");
InputStream is = conn.getInputStream();//得到网络返回的输入流
String result = readData(is, "GBK");
conn.disconnect();
//第一个参数为输入流,第二个参数为字符集编码
public static String readData(InputStream inSream, String charsetName) throws
Exception{
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = -1;
while( (len = inSream.read(buffer)) != -1 ){
outStream.write(buffer, 0, len);
}
byte[] data = outStream.toByteArray();
outStream.close();
inSream.close();
return new String(data, charsetName);
}
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4.利用HttpURLConnection对象,我们可以从网络中获取文件数据.
URL url = new URL(" http://photocdn.sohu.com/20100125/Img269812337.jpg");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5* 1000);
conn.setRequestMethod("GET");
if (conn.getResponseCode() != 200) throw new RuntimeException("请求url失败");
InputStream is = conn.getInputStream();
readAsFile(is, "Img269812337.jpg");
public static void readAsFile(InputStream inSream, File file) throws Exception{
FileOutputStream outStream = new FileOutputStream(file);
byte[] buffer = new byte[1024];
int len = -1;
while( (len = inSream.read(buffer)) != -1 ){
outStream.write(buffer, 0, len);
}
outStream.close();
inSream.close();
}
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5.需要在清单文件中加入的权限：
<!-- 访问internet权限 -->
<uses-permission android:name="android.permission.INTERNET"/>
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6.24_网络通信之网页源码查看器的代码：
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a.新建项目：HtmlViewer
/HtmlViewer/src/com/credream/htmlviewer/HtmlViewerActivity.java
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package com.credream.htmlviewer;
import com.credream.service.PageService;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.SimpleAdapter.ViewBinder;
import android.widget.Toast;
public class HtmlViewerActivity extends Activity {
private EditText pathText;
private TextView codeView;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
pathText=(EditText)this.findViewById(R.id.pagepath);
codeView=(TextView)this.findViewById(R.id.codeview);
Button button=(Button) this.findViewById(R.id.button);
button.setOnClickListener(new ButtonClickListener());
}
private final class ButtonClickListener implements View.OnClickListener
{
@Override
public void onClick(View v)
{
String path= pathText.getText().toString();
try
{
String html=PageService.getHtml(path);
codeView.setText(html);
} catch (Exception e)
{
e.printStackTrace();
Toast.makeText(getApplicationContext(), R.string.error,1).show();
}
}
}
}
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b./HtmlViewer/src/com/credream/service/PageService.java
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package com.credream.service;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import com.credream.util.StreamTool;
public class PageService
{
/**
* 获取网页的HTml代码
*/
public static String getHtml(String path) throws Exception
{
URL uri = new URL(path);
HttpURLConnection conn = (HttpURLConnection) uri.openConnection
();
conn.setConnectTimeout(5000);
conn.setRequestMethod("GET");
if (conn.getResponseCode() == 200)
{
InputStream inStream = conn.getInputStream();
byte[] data = StreamTool.read(inStream);
String html = new String(data, "UTF-8");
return html;
}
return null;
}
}
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c./HtmlViewer/src/com/credream/util/StreamTool.java
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package com.credream.util;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
/**
* 读取流中的数据
*
* @author xiaofeng
*
*/
public class StreamTool
{
public static byte[] read(InputStream inStream) throws Exception
{
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = inStream.read(buffer)) != -1)
{
outStream.write(buffer, 0, len);// 往内存写数据
}
inStream.close();
return outStream.toByteArray();
}
}
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d./HtmlViewer/res/layout/main.xml
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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=" http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/pagepath" />
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=" http://192.168.1.110:6118/web/index.html"
android:id="@+id/pagepath"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/button"
android:id="@+id/button"
/>
<!--
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/codeview" />-->
<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/codeview" />
</ScrollView>
</LinearLayout>
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e./HtmlViewer/res/values/strings.xml
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<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Hello World, HtmlViewerActivity!</string>
<string name="app_name">Html源码查看</string>
<string name="pagepath">网页路径</string>
<string name="button">查看</string>
<string name="error">读取信息错误</string>
</resources>
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f./HtmlViewer/AndroidManifest.xml
---------------------------------------
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android=" http://schemas.android.com/apk/res/android"
package="com.credream.htmlviewer"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:label="@string/app_name"
android:name=".HtmlViewerActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<!-- 访问网络权限 -->
<uses-permission android:name="android.permission.INTERNET" />
</manifest>
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7.新建web项目，并且在webroot下，新建文件index.html
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/web/WebContent/index.html
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
" http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
创梦网络<br/>
//Http watch
</body>
</html>
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