multithreading and user interface

Question

Ok, here we go. recently I got fond of HCI topics on interface design.
I found out that there could be some way to implement a multithread interface in case for reducing the delay of system respons.
Morover. this may also be possible to say that designing a user interface has tight relationship with STD.
therefore, I wonder if there is any method or techniques to find independant part of ,say,a given STD of a UI that can be seen as threads?

Answer 1

A multi threaded interface in most cases is not fundamentally different to it's single threaded counterpart. There is still a single thread listening on interface events and it will still run handlers as events happen. However the difference comes down to what is contained in these handlers. A simple single threaded event loop would look as below:

A multi-threaded UI is a little different but the principal is the same:

Effectively long processes which are initiated in worker threads which can then report back to them main UI thread so it can report completion.

In relation to a State Transition Diagram, multi-threading complicates things somewhat however there a number of ways to still accomplish this. The first is to simply map each (potential) thread's path separately, this requires decisions for if any threads are finished at the points the main thread checks. It is also possible to use a thread state transition diagram which can demonstrate many threads in a single diagram but is sometimes harder to parse.

Now regarding using a state transition diagram to help implement threading in a user interface program you simply have to locate tasks between the event handler and returning to listening which are time consuming and likely to block. You then need to dispatch these tasks as a thread, optionally adding a completion callback in the main thread.

If I have missed anything please comment below, otherwise I hope this is helpful.