android wifi 온 오프 상태 확인

public boolean isWifiOnline(FragmentActivity activity) { // network 연결 상태 확인 

        try { 
            ConnectivityManager conMan = (ConnectivityManager) activity.getSystemService(Context.CONNECTIVITY_SERVICE); 

            NetworkInfo.State wifi = conMan.getNetworkInfo(1).getState(); // wifi 
            if (wifi == NetworkInfo.State.CONNECTED || wifi == NetworkInfo.State.CONNECTING) { 
                return true; 
            } 
        } catch (NullPointerException e) { 
            return false; 
        } 
        return false; 
    }