OnStatusChanged is a TIdIPAddrMonEvent property that represents the event handler signalled when an IP address has been added or removed to the IPAddresses for the component. 

OnStatusChanged is used in a protected method that executes when calling CheckAdapters. 

Arguments passed to the event handler indicate the Thread generating the notification (or nil when ForceCheck is used), the adapter index for the altered IP address, and the previous and current values for the IP address. 

OnStatusChanged is called as a Synchronized method, and allows updating VCL components in the application as result of the event. Applications must assign a procedure to the event handler to allow responding to the event notification.

TIdIPAddrMonEvent CheckAdapters ForceCheck