Hi Matt,
I was trying to craft a simple PyQt demo to reproduce the issue, but
failed, since the craft demo just worked, any may not reflect the real
issue, the real application is too complicated to present here.
Hm, if you cannot post code that shows the problem or even describe what you are doing in any detail, I'm not sure how we can help you solve the problem you're having. We have not learned anything that might be useful to other people.
There are lots of GUIs using CA, including from Python, and using Qt. So, whatever you want to do is almost certainly possible. I have no idea why your GUIs aren't working.
The reason we cannot simply work around this issue by using Python 3.6 or
newer is that the Stretch OS (which is current deployed in our controls
network) only provides the version of 3.5.3, and it is not easy to
deploy a newer one. So looking forward the new release of pyepics. Thanks!
I'm not sure that the next version of PyEpics will support Python 3.5. I doubt anyone would make packages for Python 3.5, but I don't know that we'll intentionally break support for Python 3.5 for the next release. But when we drop support for Python 2.7, we will also drop support for 3.5. Don't plan on either being supported in a year.
Using system Python is definitely anti-recommended. Python is very easy to install and using environments can allow multiple versions of Python or installed packages. Using such a dedicated environment is definitely recommended for any user-space application, especially something as complicated as a GUI application using pyepics.