android wifi 的开启，关闭，查询等。

有问题请加：Q群： 241359063  共同走向创业学习之旅。
原创：kylin_zeng  http://blog.chinaunix.net/uid/23795897.html
在此感谢mars 老师的帮助。转载请注明原创出处，尊重他人的劳动成果。

点击(此处)折叠或打开

1. <!-- 以下是使用wifi访问网络所需要的权限 -->
   
2.     <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"></uses-permission>
   
3.     <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>
   
4.     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
   
5.     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>

点击(此处)折叠或打开

1. package mars.wifi;
   
2. 
   
3. import android.app.Activity;
   
4. import android.content.Context;
   
5. import android.net.wifi.WifiManager;
   
6. import android.os.Bundle;
   
7. import android.view.View;
   
8. import android.view.View.OnClickListener;
   
9. import android.widget.Button;
   
10. import android.widget.Toast;
    
11. 
    
12. public class WifiActivity extends Activity {
    
13.     /** Called when the activity is first created. */
    
14.     private Button startButton = null;
    
15.     private Button stopButton = null;
    
16.     private Button checkButton = null;
    
17.     private WifiManager wifiManager = null;
    
18.     @Override
    
19.     public void onCreate(Bundle savedInstanceState) {
    
20.         super.onCreate(savedInstanceState);
    
21.         setContentView(R.layout.main);
    
22.         startButton = (Button)findViewById(R.id.startWifi);
    
23.         stopButton = (Button)findViewById(R.id.stopWifi);
    
24.         checkButton = (Button)findViewById(R.id.checkWifi);
    
25.         startButton.setOnClickListener(new StartWifiListener());
    
26.         stopButton.setOnClickListener(new StopWifiListener());
    
27.         checkButton.setOnClickListener(new CheckWifiListener());
    
28.     }
    
29.     class StartWifiListener implements OnClickListener{
    
30. 
    
31.         @Override
    
32.         public void onClick(View v) {  
33.      //WifiActivity.this 此处本来是要用context的，但是activity是继承context，所有可以用activity,又因这里是在StartWifiListener class里面，如果只用this，没有用WifiActivity.this，就只在这个class里面。
    
34.       //Context.WIFI_SERVICE,同理，context继承services
35.             wifiManager = (WifiManager)WifiActivity.this.getSystemService(Context.WIFI_SERVICE);
    
36.             wifiManager.setWifiEnabled(true);
    
37.             System.out.println("wifi state --->" + wifiManager.getWifiState());
    
38.             Toast.makeText(WifiActivity.this, "当前Wifi网卡状态为" + wifiManager.getWifiState(), Toast.LENGTH_SHORT).show();
    
39.         }
    
40.     }
    
41.     class StopWifiListener implements OnClickListener{
    
42. 
    
43.         @Override
    
44.         public void onClick(View arg0) {
    
45.             // TODO Auto-generated method stub
    
46.             wifiManager = (WifiManager)WifiActivity.this.getSystemService(Context.WIFI_SERVICE);
    
47.             wifiManager.setWifiEnabled(false);
    
48.             System.out.println("wifi state --->" + wifiManager.getWifiState());
    
49.             Toast.makeText(WifiActivity.this, "当前Wifi网卡状态为" + wifiManager.getWifiState(), Toast.LENGTH_SHORT).show();
    
50.         }
    
51.     
    
52.     }
    
53.     
    
54.     class CheckWifiListener implements OnClickListener{
    
55. 
    
56.         @Override
    
57.         public void onClick(View v) {
    
58.             wifiManager = (WifiManager)WifiActivity.this.getSystemService(Context.WIFI_SERVICE);
    
59.             System.out.println("wifi state --->" + wifiManager.getWifiState());
    
60.             Toast.makeText(WifiActivity.this, "当前Wifi网卡状态为" + wifiManager.getWifiState(), Toast.LENGTH_SHORT).show();
    
61.         }
    
62.         
    
63.     }
    
64. }

mars视频教程ppt和代码01_23_ppt_src.zip