Writing a Chat Application in C++
pokemon123 last edited by
I am trying to make a chat application. I use Qt (for the GUI) and Boost.Asio (for socket programming function calls).
I want to establish a connection between the client and server before I show the client's GUI. However, when I set up the connection, I use a function called io_service.run() which is a blocking call. Basically, it is an event loop queueing and executing read and write messages. Since this is a blocking call, it will not reach a.exec() which shows the GUI. So I end up with a black window, instead of the GUI.
How do I fix this?
Thank you. :)
Pl45m4 last edited by Pl45m4
Why you want to use Asio? You can do the whole Chat App (GUI + network connection) with Qt only.
a.exec()will start its own event loop for GUI, so it's not that easy to make
io_service.run()work with Qt.
You could try to run your
io_servicein a different boost::thread, but I don't know, if everything will work as expected
KH-219Design last edited by
Another option (if you are bound and determined to use as few threads as humanly possible, for whatever reason you may have):
You can use a
QTimerthat "ticks" every N milliseconds (you choose N), and you can invoke other methods on your
io_serviceinstance instead of invoking
run(). For example you could use io_service::run_for to constrain the length of "timeslice" you yield to the
There are a number of similar methods, such as
In this way, you can achieve a sort of cooperative, voluntary yielding, time-slicing where the
io_serviceuses the main/GUI thread, but it never blocks it for very long.