GUI program with parfeval

Hello Matlab community, I'm enhancing a GUI program with mouse events and simultaneously accessing an online database. My idea to avoid GUI hangs while querying the database is as follows:

thread_ptr = parfeval(@(c, varargin) fetch(c.Value, varargin{:}), 1, c, query);

pause(3) % not stop mouse events during query

data = fetchOutputs(thread_ptr);

This code seems to work, but I want some pause() function that stops when parfeval stops running. I have already tried wait() , but apparentelly wait() also seems to stop the GUI. Any ideas?

Answer 1

[Edric Ellis]

You should be able to cause the GUI to update by using wait in a loop, together with drawnow. A bit like this:

while ~wait(thread_ptr, 'finished', 0.1) % wait for 0.1 seconds
    drawnow % update the UI if the future wasn't finished
end

A slightly different approach might actually work better here. You can use afterEach with parfeval to automatically run a function when your evaluation on the worker completes. (More details on this page). Something a bit like this

thread_ptr = parfeval(..);
afterEach(thread_ptr, @(result) doStuffWithResult(result), 0)

In this way, doStuffWithResult automatically gets called with the outputs from thread_ptr as soon as they are available.

[HILTON MARQUES SANTANA]

Thanks!