networking - Detect wifi IP address on Android?

Question

I need to determine if the Android device is connected to Wifi, and if so, obtain its Wifi IP address.

I know how to use ConnectivityManager to determine whether the active network is a Wifi network, and I know how to use java.net.NetworkInterface to iterate over the available network interfaces and get their IP addresses.

What I don't know how to do is determine which IP address belongs to the Wifi network, if there is more than one address found. Any advice?

Thanks.

Answer 1

public String getIpAddr() {
   WifiManager wifiManager = (WifiManager) getSystemService(WIFI_SERVICE);
   WifiInfo wifiInfo = wifiManager.getConnectionInfo();
   int ip = wifiInfo.getIpAddress();

   String ipString = String.format(
   "%d.%d.%d.%d",
   (ip & 0xff),
   (ip >> 8 & 0xff),
   (ip >> 16 & 0xff),
   (ip >> 24 & 0xff));

   return ipString;
}

Please Note: You need to add android.permission.INTERNET and android.permission.ACCESS_WIFI_STATE in your AndroidManifest.xml as <user-permission/> to access the code.

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />