CHANGE_WIFI_MULTICAST_STATE. The wrapper makes the following information available: wifi enabled, wifi state, and ping supplicant. Plus the following additional information: BSSID, HiddenSSID, ip address, link speed, mac address, network ID, RSSI, SSID, and supplicant state. It also shows an example of listing the access point SSIDs which are in range of your Android device. The wrapper is a unit called Androidapi.JNI.Net.Wifi. Here is the sample code for reading the wifi information with the wrapper:
var
WifiManagerObj: JObject;
WifiManager: JWifiManager;
WifiInfo: JWifiInfo;
begin
WifiManagerObj := SharedActivityContext.getSystemService(TJContext.JavaClass.WIFI_SERVICE);
WifiManager := TJWifiManager.Wrap((WifiManagerObj as ILocalObject).GetObjectID);
WifiInfo := WifiManager.getConnectionInfo();
Label1.Text := 'Wifi Enabled: ' + WifiManager.isWifiEnabled.ToString;
Label2.Text := 'Wifi State: ' + WifiManager.getWifiState.ToString;
Label3.Text := 'Ping Supplicant: ' + WifiManager.pingSupplicant.ToString;
Memo1.Lines.Clear;
Memo1.Lines.Add('BSSID: ' + JStringToString(WifiInfo.getBSSID));
Memo1.Lines.Add('HiddenSSID: ' + WifiInfo.getHiddenSSID.ToString);
Memo1.Lines.Add('IpAddress: ' + WifiInfo.getIpAddress.ToString);
Memo1.Lines.Add('LinkSpeed: ' + WifiInfo.getLinkSpeed.ToString + 'Mbps');
Memo1.Lines.Add('MacAddress: ' + JStringToString(WifiInfo.getMacAddress));
Memo1.Lines.Add('NetworkId: ' + WifiInfo.getNetworkId.ToString);
Memo1.Lines.Add('Rssi: ' + WifiInfo.getRssi.ToString + 'dBm');
Memo1.Lines.Add('SSID: ' + JStringToString(WifiInfo.getSSID));
Memo1.Lines.Add('SupplicantState: ' + JStringToString(WifiInfo.getSupplicantState.toString));
The original blog post is in Russian so use Google Chrome to translate. This code should also work in AppMethod.