Android study note 09. WiFi network operations

1. Concepts

2. WiFi Nic status

Wifi_state_disabled: WiFi Nic unavailable (1)

Wifi_state_disabling: WiFi is being disabled (0)

Wifi_state_enabled: WiFi Nic available (3)

Wifi_state_enabling: the WiFi Nic is on (2)

Wifi_state_unknown: Unknown Nic status

3. WiFi permission

(Some network-related permissions. For other permissions, see the help documentation)

4. Change the status of the Wi-Fi network card

To operate a Wi-Fi network card, you need to perform the wifimanager object as follows:

Wifimanager = (wifimanager) Context. getsystemservice (service. wifi_service );

Enable the NIC: wifimanager. setwifienabled (true );

Disable the WiFi NIC: wifimanager. setwifienabled (false );

Obtain the current Nic status: wifimanager. getwifistate ();

Now a Wi-Fi access is implementedProgramYou must have an Android mobile phone for testing. The specific content is to start, stop, and view the Wi-Fi network.

Wifiactivity. Java

 1   Package  Zzl. 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. Menu;  8   Import  Android. View. view;  9   Import  Android. View. View. onclicklistener;  10  Import  Android. widget. Button;  11   Import  Android. widget. Toast;  12   13   Public   Class Wifiactivity Extends  Activity {  14   15       Private Button start = Null  ; 16       Private Button stop = Null  ;  17       Private Button check = Null  ;  18       Private Wifimanager = Null  ;  19   @ Override  20       Protected  Void  Oncreate (bundle savedinstancestate ){  21           Super  . Oncreate (savedinstancestate );  22   Setcontentview (R. layout. Main );  23           24 Start = (Button) findviewbyid (R. Id. Start );  25 Stop = (Button) findviewbyid (R. Id. Stop );  26 Check =(Button) findviewbyid (R. Id. Check );  27           28 Start. setonclicklistener ( New  Startwifilistener ());  29 Stop. setonclicklistener ( New  Stopwifilistener ());  30 Check. setonclicklistener ( New  Checkwifilistener ());  31   }  32  33       Class Startwifilistener Implements  Onclicklistener {  34   35   @ Override  36           Public   Void  Onclick (view v ){  37               //  Todo auto-generated method stub  38               // Wifiactivity inherits from activity,  39               //  Activity itself is a subclass of context (so all functions of context can be used by activity)  40 Wifimanager = (wifimanager) wifiactivity. This  . Getsystemservice (context. wifi_service );  41 Wifimanager. setwifienabled ( True  );  42 System. Out. println ("wiif State --->" + Wifimanager. getwifistate ()); 43 Toast. maketext (wifiactivity. This , "Current WiFi status:" + Wifimanager. getwifistate (), Toast. length_short). Show ();  44   }  45   }  46       Class Stopwifilistener Implements  Onclicklistener {  47   48   @ Override 49           Public   Void  Onclick (view v ){  50               //  Todo auto-generated method stub  51 Wifimanager = (wifimanager) wifiactivity. This  . Getsystemservice (context. wifi_service );  52 Wifimanager. setwifienabled ( False  );  53 System. Out. println ("wiif State --->" + Wifimanager. getwifistate ());  54 Toast. maketext (wifiactivity. This , "Current WiFi status:" + Wifimanager. getwifistate (), Toast. length_short). Show ();  55   }  56   }  57       Class Checkwifilistener Implements  Onclicklistener {  58  59   @ Override  60           Public   Void  Onclick (view v ){  61               //  Todo auto-generated method stub  62 Wifimanager = (wifimanager) wifiactivity. This  . Getsystemservice (context. wifi_service );  63 System. Out. println ("wiif State --->" +Wifimanager. getwifistate ());  64 Toast. maketext (wifiactivity. This , "Current WiFi status:" + Wifimanager. getwifistate (), Toast. length_short). Show ();  65   }  66   }  67   @ Override  68       Public   Boolean  Oncreateoptionsmenu (menu ){ 69           //  Inflate the menu; this adds items to the action bar if it is present.  70   Getmenuinflater (). Inflate (R. Menu. Main, menu );  71           Return   True  ;  72   }  73   74 }

Main. xml

 1   < Linearlayout  Xmlns: Android  = "Http://schemas.android.com/apk/res/android"  2   Xmlns: Tools  = "Http://schemas.android.com/tools"  3   Android: Orientation  = "Vertical"  4   Android: layout_width  = "Match_parent"  5   Android: layout_height = "Match_parent"  6   Tools: Context  = ". Wifiactivity"   >  7   8       <  Button  9           Android: layout_width  = "Fill_parent"  10   Android: layout_height  = "Wrap_content"  11  Android: ID  = "@ + ID/start"  12   Android: Text  = "@ String/start"  />  13       <  Button  14           Android: layout_width  = "Fill_parent"  15   Android: layout_height  = "Wrap_content"  16  Android: ID  = "@ + ID/stop"  17   Android: Text  = "@ String/stop"  />  18       <  Button  19           Android: layout_width  = "Fill_parent"  20   Android: layout_height  = "Wrap_content"  21  Android: ID  = "@ + ID/check"  22   Android: Text  = "@ String/check"  />  23   24   </  Linearlayout  > 

Partial results:

Summary:

(1. The <uses-Permission> tag appears after <Application> tag warning appears in manifest. xml.

Solution:Put <uses-Permission> in front of <Application>

(2) To enable Wi-Fi access to the network, you need to write such information in manifest. xml.CodeOtherwise, the access permission may be insufficient.

 1        <  Uses-Permission  Android: Name  = "Android. Permission. change_network_state"  > </  Uses-Permission  >  2        <  Uses-Permission Android: Name  = "Android. Permission. change_wifi_state"  > </  Uses-Permission  >  3        <  Uses-Permission  Android: Name  = "Android. Permission. access_network_state"  > </  Uses-Permission  >  4        < Uses-Permission  Android: Name  = "Android. Permission. access_wifi_state"  > </  Uses-Permission  > 

(3. connect to your mobile phone for testing.