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

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<?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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