在Kotlin中，没有Formatter

private fun getIPAddress(useIPv4 : Boolean): String {
    try {
        var interfaces = Collections.list(NetworkInterface.getNetworkInterfaces())
        for (intf in interfaces) {
            var addrs = Collections.list(intf.getInetAddresses());
            for (addr in addrs) {
                if (!addr.isLoopbackAddress()) {
                    var sAddr = addr.getHostAddress();
                    var isIPv4: Boolean
                    isIPv4 = sAddr.indexOf(':')<0
                    if (useIPv4) {
                        if (isIPv4)
                            return sAddr;
                    } else {
                        if (!isIPv4) {
                            var delim = sAddr.indexOf('%') // drop ip6 zone suffix
                            if (delim < 0) {
                                return sAddr.toUpperCase()
                            }
                            else {
                                return sAddr.substring(0, delim).toUpperCase()
                            }
                        }
                    }
                }
            }
        }
    } catch (e: java.lang.Exception) { }
    return ""
}

你可以使用LinkProperties。建议用于新的Android版本。

此功能检索WiFi和移动数据的本地IP地址。它需要Manifest.permission。ACCESS_NETWORK_STATE许可。

@Nullable
public static String getDeviceIpAddress(@NonNull ConnectivityManager connectivityManager) {
    LinkProperties linkProperties = connectivityManager.getLinkProperties(connectivityManager.getActiveNetwork());
    InetAddress inetAddress;
    for(LinkAddress linkAddress : linkProperties.getLinkAddresses()) {
        inetAddress = linkAddress.getAddress();
        if (inetAddress instanceof Inet4Address
                && !inetAddress.isLoopbackAddress()
                && inetAddress.isSiteLocalAddress()) {
            return inetAddress.getHostAddress();
        }
    }
    return null;
}

您不需要像目前提供的解决方案那样添加权限。以字符串形式下载此网站:

http://www.ip-api.com/json

or

http://www.telize.com/geoip

下载一个网站作为字符串可以用java代码完成:

http://www.itcuties.com/java/read-url-to-string/

像这样解析JSON对象:

https://stackoverflow.com/a/18998203/1987258

json属性“query”或“ip”包含ip地址。

虽然有一个正确的答案，我在这里分享我的答案，希望这样会更方便。

WifiManager wifiMan = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInf = wifiMan.getConnectionInfo();
int ipAddress = wifiInf.getIpAddress();
String ip = String.format("%d.%d.%d.%d", (ipAddress & 0xff),(ipAddress >> 8 & 0xff),(ipAddress >> 16 & 0xff),(ipAddress >> 24 & 0xff));

方法getDeviceIpAddress返回设备的ip地址，如果连接了wifi接口，则首选wifi接口地址。

  @NonNull
    private String getDeviceIpAddress() {
        String actualConnectedToNetwork = null;
        ConnectivityManager connManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        if (connManager != null) {
            NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
            if (mWifi.isConnected()) {
                actualConnectedToNetwork = getWifiIp();
            }
        }
        if (TextUtils.isEmpty(actualConnectedToNetwork)) {
            actualConnectedToNetwork = getNetworkInterfaceIpAddress();
        }
        if (TextUtils.isEmpty(actualConnectedToNetwork)) {
            actualConnectedToNetwork = "127.0.0.1";
        }
        return actualConnectedToNetwork;
    }

    @Nullable
    private String getWifiIp() {
        final WifiManager mWifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
        if (mWifiManager != null && mWifiManager.isWifiEnabled()) {
            int ip = mWifiManager.getConnectionInfo().getIpAddress();
            return (ip & 0xFF) + "." + ((ip >> 8) & 0xFF) + "." + ((ip >> 16) & 0xFF) + "."
                    + ((ip >> 24) & 0xFF);
        }
        return null;
    }


    @Nullable
    public String getNetworkInterfaceIpAddress() {
        try {
            for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements(); ) {
                NetworkInterface networkInterface = en.nextElement();
                for (Enumeration<InetAddress> enumIpAddr = networkInterface.getInetAddresses(); enumIpAddr.hasMoreElements(); ) {
                    InetAddress inetAddress = enumIpAddr.nextElement();
                    if (!inetAddress.isLoopbackAddress() && inetAddress instanceof Inet4Address) {
                        String host = inetAddress.getHostAddress();
                        if (!TextUtils.isEmpty(host)) {
                            return host;
                        }
                    }
                }

            }
        } catch (Exception ex) {
            Log.e("IP Address", "getLocalIpAddress", ex);
        }
        return null;
    }

WifiManager wm = (WifiManager) getSystemService(WIFI_SERVICE);
String ipAddress = BigInteger.valueOf(wm.getDhcpInfo().netmask).toString();