The second part of the solution deals with sending messages back to the parent. As I've mentioned before, you already have several possibilities to do the same with built-in Delphi functions. They all work well in combination with the previously described method for sending messages to a thread. This second part is therefore purely optional, but I believe it is a good solution, because it centralizes the message-handling for each thread.
Again, the code starts by creating a TThreadedQueue<TValue> to store sent values. We cannot use an event to signal new messages, though. Delphi forms interact with the operating system and with the user by constantly processing messages, and we cannot block this message processing ...
