想要在代码中实现设置WIFI静态IP需要有系统权限，要在manifest文件添加android:sharedUserId=“android.uid.system”，还要有系统签名。
设置WIFI静态IP和之前以太网的类似，都是要构造StaticIpConfiguration对象，以及IpConfiguration.IpAssignment.STATIC就代表设置为静态IP，也可以设置DHCP（自动获取），不过WifiConfiguration可以直接通过WifiManager获取到，比设置以太网的要简单一些，不用反射来获取对象。

将IP，NETMASK，GATEWAY和DNS设置进去，构造StaticIpConfiguration对象，下边是代码：

try {Inet4Address inetAddr = getIPv4Address(STATIC_IP);int prefixLength = NetUtils.maskStr2InetMask(STATIC_NETMASK);InetAddress gatewayAddr = getIPv4Address(STATIC_GATEWAY);InetAddress dnsAddr = getIPv4Address(STATIC_DNS1);Class[] cl = new Class[]{InetAddress.class, int.class};Constructor cons = null;Class<?> clazz = Class.forName("android.net.LinkAddress");//取得所有构造函数try {cons = clazz.getConstructor(cl);} catch (NoSuchMethodException e) {e.printStackTrace();}if (cons == null) {return;}//给传入参数赋初值Object[] x = {inetAddr, prefixLength};//构造StaticIpConfiguration对象Class<?> staticIpConfigurationCls = Class.forName("android.net.StaticIpConfiguration");//实例化StaticIpConfigurationObject staticIpConfiguration = null;staticIpConfiguration = staticIpConfigurationCls.newInstance();Field ipAddress = staticIpConfigurationCls.getField("ipAddress");Field gateway = staticIpConfigurationCls.getField("gateway");Field dnsServers = staticIpConfigurationCls.getField("dnsServers");//设置ipAddressipAddress.set(staticIpConfiguration, (LinkAddress) cons.newInstance(x));//设置网关gateway.set(staticIpConfiguration, gatewayAddr);//设置dnsArrayList<InetAddress> dnsList = (ArrayList<InetAddress>) dnsServers.get(staticIpConfiguration);dnsList.add(dnsAddr);if (!STATIC_DNS2.isEmpty()) {dnsList.add(getIPv4Address(STATIC_DNS2));}WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(WIFI_SERVICE);WifiConfiguration wifiConfig = null;WifiInfo connectionInfo = wifiManager.getConnectionInfo(); //得到连接的wifi网络@SuppressLint("MissingPermission")List<WifiConfiguration> configuredNetworks = wifiManager.getConfiguredNetworks();for (WifiConfiguration conf : configuredNetworks) {if (conf.networkId == connectionInfo.getNetworkId()) {wifiConfig = conf;break;}}@SuppressLint("PrivateApi") Class ipAssignmentCls = Class.forName("android.net.IpConfiguration$IpAssignment");Object ipAssignment = Enum.valueOf(ipAssignmentCls, "STATIC");Method setIpAssignmentMethod = wifiConfig.getClass().getDeclaredMethod("setIpAssignment", ipAssignmentCls);setIpAssignmentMethod.invoke(wifiConfig, ipAssignment);Method setStaticIpConfigurationMethod = wifiConfig.getClass().getDeclaredMethod("setStaticIpConfiguration", staticIpConfiguration.getClass());//设置静态IP，将StaticIpConfiguration设置给WifiConfigurationsetStaticIpConfigurationMethod.invoke(wifiConfig, staticIpConfiguration);//WifiConfiguration重新添加到WifiManager int netId = wifiManager.addNetwork(wifiConfig);wifiManager.disableNetwork(netId);boolean flag = wifiManager.enableNetwork(netId, true);} catch (NoSuchFieldException | IllegalAccessException | InstantiationException | InvocationTargetException | ClassNotFoundException | NoSuchMethodException e) {e.printStackTrace();}

通过WifiConfiguration的setStaticIpConfiguration方法将StaticIpConfiguration对象设置进去，通过setIpAssignment，将IpAssignment设置进去，值设为STATIC，最后根据netId 重启这个网络，即可将静态IP设置成功。