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));

public static String getLocalIpAddress() {
    try {
        for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
            NetworkInterface intf = en.nextElement();
            for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
                InetAddress inetAddress = enumIpAddr.nextElement();
                if (!inetAddress.isLoopbackAddress() && inetAddress instanceof Inet4Address) {
                    return inetAddress.getHostAddress();
                }
            }
        }
    } catch (SocketException ex) {
        ex.printStackTrace();
    }
    return null;
}

我已经添加了inetAddress instanceof Inet4Address来检查它是否是ipv4地址。

我不使用Android，但我会用完全不同的方式来解决这个问题。

发送一个查询到谷歌，像这样: https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=my%20ip

并引用发布响应的HTML字段。您也可以直接查询到源。

谷歌最可能比你的应用程序存在的时间长。

只要记住，这可能是你的用户在这个时候没有互联网，你希望发生什么!

祝你好运

请检查这个代码…使用此代码。我们将从移动互联网获得IP…

for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements(); ) {
                NetworkInterface intf = en.nextElement();
                for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements(); ) {
                    InetAddress inetAddress = enumIpAddr.nextElement();
                    if (!inetAddress.isLoopbackAddress()) {
                        return inetAddress.getHostAddress().toString();
                    }
                }
            }

在AndroidManifest.xml中声明ACCESS_WIFI_STATE权限:

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

可以通过WifiManager获取IP地址:

Context context = requireContext().getApplicationContext();
WifiManager wm = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
String ip = Formatter.formatIpAddress(wm.getConnectionInfo().getIpAddress());

 //    @NonNull
    public static String getIPAddress() {
        if (TextUtils.isEmpty(deviceIpAddress))
            new PublicIPAddress().execute();
        return deviceIpAddress;
    }

    public static String deviceIpAddress = "";

    public static class PublicIPAddress extends AsyncTask<String, Void, String> {
        InetAddress localhost = null;

        protected String doInBackground(String... urls) {
            try {
                localhost = InetAddress.getLocalHost();
                URL url_name = new URL("http://bot.whatismyipaddress.com");
                BufferedReader sc = new BufferedReader(new InputStreamReader(url_name.openStream()));
                deviceIpAddress = sc.readLine().trim();
            } catch (Exception e) {
                deviceIpAddress = "";
            }
            return deviceIpAddress;
        }

        protected void onPostExecute(String string) {
            Lg.d("deviceIpAddress", string);
        }
    }