一个设备可能有几个IP地址，在一个特定的应用程序中使用的IP地址可能不是接收请求的服务器将看到的IP地址。事实上，一些用户使用VPN或Cloudflare Warp等代理。

如果你的目的是获得IP地址，就像服务器从你的设备接收请求一样，那么最好是通过Java客户端查询IP地理定位服务，如Ipregistry(免责声明:我为该公司工作):

https://github.com/ipregistry/ipregistry-java

IpregistryClient client = new IpregistryClient("tryout");
RequesterIpInfo requesterIpInfo = client.lookup();
requesterIpInfo.getIp();

除了使用非常简单之外，您还可以获得其他信息，例如国家、语言、货币、设备IP的时区，并且您可以识别用户是否正在使用代理。

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());

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。

在你的活动中，下面的函数getIpAddress(context)返回电话的IP地址:

public static String getIpAddress(Context context) {
    WifiManager wifiManager = (WifiManager) context.getApplicationContext()
                .getSystemService(WIFI_SERVICE);

    String ipAddress = intToInetAddress(wifiManager.getDhcpInfo().ipAddress).toString();

    ipAddress = ipAddress.substring(1);

    return ipAddress;
}

public static InetAddress intToInetAddress(int hostAddress) {
    byte[] addressBytes = { (byte)(0xff & hostAddress),
                (byte)(0xff & (hostAddress >> 8)),
                (byte)(0xff & (hostAddress >> 16)),
                (byte)(0xff & (hostAddress >> 24)) };

    try {
        return InetAddress.getByAddress(addressBytes);
    } catch (UnknownHostException e) {
        throw new AssertionError();
    }
}

这里是@Nilesh和@anargund的kotlin版本

  fun getIpAddress(): String {
    var ip = ""
    try {
        val wm = applicationContext.getSystemService(WIFI_SERVICE) as WifiManager
        ip = Formatter.formatIpAddress(wm.connectionInfo.ipAddress)
    } catch (e: java.lang.Exception) {

    }

    if (ip.isEmpty()) {
        try {
            val en = NetworkInterface.getNetworkInterfaces()
            while (en.hasMoreElements()) {
                val networkInterface = en.nextElement()
                val enumIpAddr = networkInterface.inetAddresses
                while (enumIpAddr.hasMoreElements()) {
                    val inetAddress = enumIpAddr.nextElement()
                    if (!inetAddress.isLoopbackAddress && inetAddress is Inet4Address) {
                        val host = inetAddress.getHostAddress()
                        if (host.isNotEmpty()) {
                            ip =  host
                            break;
                        }
                    }
                }

            }
        } catch (e: java.lang.Exception) {

        }
    }

   if (ip.isEmpty())
      ip = "127.0.0.1"
    return ip
}

public static String getdeviceIpAddress() {
    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;
}