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！");
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。
时间： 2024-10-14 06:48:49