知道wifi何时连接到特定的SSID

Question

I am developing an app in which I need to start a service when the WiFi is connected to a predefined SSID. Can anyone help me with this? Is there a broadcast in android that is fired when WiFi is connected (not turned on) ?

Answer 1

Yes, its called ConnectivityManager :

ConnectivityManager conMan = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); 
NetworkInfo netInfo = conMan.getActiveNetworkInfo();

You can use getType() to check whether it is a WiFi connection:

netInfo.getType() == ConnectivityManager.TYPE_WIFI

See this post for more information.

EDIT

To obtain the SSID try:

WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
WifiInfo connectionInfo = wifiManager.getConnectionInfo();
connectionInfo.getSSID();

as seen here

Answer 2

Yes, there's a Broadcast for this: NETWORK_STATE_CHANGED_ACTION . When the new state is CONNECTED, the Intent includes the BSSID as an extra (cf. the documentation linked above). You can check the state via the included NetworkInfo object.