安卓http源码查看器详解
1.效果图如下，输入网址就可以看到该网址的源码
2.项目工程文件如右图所示：
3.首先，布局文件如下，我采用的是线性布局
1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 xmlns:tools="http://schemas.android.com/tools" 3 android:layout_width="match_parent" 4 android:layout_height="match_parent" 5 android:orientation="vertical" 6 > 7 <EditText 8 android:id="@+id/et_info" 9 android:layout_width="match_parent" 10 android:layout_height="wrap_content" 11 android:text="http://" /> 12 <Button 13 android:onClick="click" 14 android:layout_width="wrap_content" 15 android:layout_height="wrap_content" 16 android:layout_gravity="center_horizontal" 17 android:text="查看源码" /> 18 <ScrollView 19 android:layout_width="match_parent" 20 android:layout_height="match_parent" 21 > 22 <TextView 23 android:id="@+id/tv_info" 24 android:layout_width="match_parent" 25 android:layout_height="match_parent" 26 /> 27 </ScrollView> 28 29 </LinearLayout>
4.MainActivity代码如下所示：采用子线程，因为安卓4.0版本以上不支持主线程。
1 package com.xunfang.look; 2 3 import java.io.InputStream; 4 import java.net.HttpURLConnection; 5 import java.net.MalformedURLException; 6 import java.net.URL; 7 import java.net.URLConnection; 8 9 import com.xunfang.service.StreamUtils; 10 11 import android.app.Activity; 12 import android.os.Bundle; 13 import android.os.Handler; 14 import android.os.Message; 15 import android.text.TextUtils; 16 import android.view.Menu; 17 import android.view.MenuItem; 18 import android.view.View; 19 import android.widget.EditText; 20 import android.widget.TextView; 21 import android.widget.Toast; 22 23 24 public class MainActivity extends Activity { 25 protected static final int SUCCESS = 1; 26 protected static final int ERROR = 2; 27 protected static final int FAULED = 3; 28 private EditText et; 29 private TextView tv; 30 31 //此方法由主线程调用 32 private Handler handler = new Handler(){ 33 public void handleMessage(Message msg) { 34 int type = msg.what; 35 switch (type) { 36 case SUCCESS: 37 String info = (String) msg.obj; 38 tv.setText(info); 39 break; 40 case ERROR: 41 //Toast.makeText(getApplicationContext(), "网络连接错误，请稍后再试", 0).show(); 42 String error = (String) msg.obj; 43 Toast.makeText(getApplicationContext(), error, 0).show(); 44 break; 45 case FAULED: 46 String fail = (String) msg.obj; 47 Toast.makeText(getApplicationContext(), fail, 0).show(); 48 break; 49 default: 50 break; 51 } 52 }; 53 }; 54 @Override 55 protected void onCreate(Bundle savedInstanceState) { 56 super.onCreate(savedInstanceState); 57 setContentView(R.layout.activity_main); 58 et = (EditText) findViewById(R.id.et_info); 59 tv = (TextView) findViewById(R.id.tv_info); 60 61 } 62 public void click(View view){ 63 new Thread(){ 64 public void run(){ 65 //获取路径 66 String path = et.getText().toString().trim(); 67 68 if(TextUtils.isEmpty(path)){ 69 System.out.println("路径不能为空！");
return ; 70 } 71 try { 72 URL uri = new URL(path); 73 //连接到服务器 74 HttpURLConnection http = (HttpURLConnection) uri.openConnection(); 75 //设置响应时间 76 http.setConnectTimeout(5000); 77 //拿到返回的状态码 78 int n = http.getResponseCode(); 79 80 if(n == 200){ 81 //接收服务器返回的内容 82 InputStream is = http.getInputStream(); 83 //从流中解析出字符串 84 String info = StreamUtils.readStream(is); 85 //c创建消息 86 Message msg = Message.obtain(); 87 //设置消息内容 88 msg.obj = info; 89 //类型 90 msg.what = SUCCESS; 91 //发送消息 92 handler.sendMessage(msg) ; 93 }else{ 94 Message msg = Message.obtain(); 95 msg.obj = "请求失败"; 96 msg.what = FAULED; 97 handler.sendMessage(msg); 98 99 } 100 101 } catch (Exception e) { 102 e.printStackTrace(); 103 Message msg = Message.obtain(); 104 msg.obj = "网络不通，请稍后再试"; 105 msg.what = ERROR; 106 handler.sendMessage(msg) ; 107 } 108 } 109 }.start(); 110 } 111 112 }
5.IO流，从给定的流中读取所有的数据转成字符串，因为要接收服务器的数据
1 package com.xunfang.service; 2 3 import java.io.ByteArrayOutputStream; 4 import java.io.IOException; 5 import java.io.InputStream; 6 7 public class StreamUtils { 8 //从给定的流中读取所有的数据转成字符串 9 public static String readStream(InputStream is) { 10 try { 11 byte[] bs = new byte[1024]; 12 int b = 0; 13 //捕获内存缓冲区的数据,转换成字节数组 14 ByteArrayOutputStream boas = new ByteArrayOutputStream(); 15 16 while((b=is.read(bs))!= -1){ 17 /* write(byte[] b, int off, int len), 18 将指定 byte数组中从偏移量 off 开始的 len 个字节写入此 byte 数组输出流。 19 b - 数据。 20 off - 数据的初始偏移量。 21 len - 要写入的字节数。 */ 22 boas.write(bs, 0, b); 23 } 24 boas.close(); 25 return new String(bs); 26 27 } catch (Exception e) { 28 e.printStackTrace(); 29 } 30 31 return null; 32 } 33 }
6，最后就是要哦添加访问网络的权限，配置文件如下：
1 <?xml version="1.0" encoding="utf-8"?> 2 <manifest xmlns:android="http://schemas.android.com/apk/res/android" 3 package="com.xunfang.look" 4 android:versionCode="1" 5 android:versionName="1.0" > 6 7 <uses-sdk 8 android:minSdkVersion="16" 9 android:targetSdkVersion="16" /> 10 <uses-permission android:name="android.permission.INTERNET"/> 11 <application 12 android:allowBackup="true" 13 android:icon="@drawable/ic_launcher" 14 android:label="@string/app_name" 15 android:theme="@style/AppTheme" > 16 <activity 17 android:name=".MainActivity" 18 android:label="@string/app_name" > 19 <intent-filter> 20 <action android:name="android.intent.action.MAIN" /> 21 <category android:name="android.intent.category.LAUNCHER" /> 22 </intent-filter> 23 </activity> 24 </application> 25 26 </manifest>
7，简单六步就完成了操作。
