Here you can find the source of isOnWifi(Context context)
public static boolean isOnWifi(Context context)
//package com.java2s; import android.content.Context; import android.net.wifi.WifiManager; public class Main { public static boolean isOnWifi(Context context) { WifiManager lWifiManager = (WifiManager) context .getSystemService(Context.WIFI_SERVICE); return lWifiManager == null ? false : lWifiManager.isWifiEnabled() && lWifiManager.getConnectionInfo() != null && lWifiManager.getConnectionInfo().getIpAddress() != 0; }/*from w w w .ja v a 2s . com*/ }