Cura periodically freezes if printer is turned off

[Troutzorz]

Cura Version 4.7.1
Printer: Flsun QQ-S Pro
Wifi Plugin Version: commit 9efec8f / pull request #37

The problem occurs when cura is open and the printer is off. Cura's UI freezes for about 2 seconds every 2 seconds. This effects the main window, 3d build preview, all menus, and even pop-out menus. This is very disruptive to the user experience. When the printer is turned on and boots up, cura returns to expected behavior.
I suspect the wifi plugin is searching for the printer on the main UI thread and blocking the UI from updating. I recommend searching for the printer in a background thread or figuring out some sort of async mechanism to run the search.

[Jeredian]

Hi, this issue already exists: #36

Here are the lines where it happens:

https://github.com/Jeredian/mks-wifi-plugin/blob/6edac06388a3fadbebf769b08ad3cd5991c75d3a/MKSWifiPlugin/MKSOutputDevice.py#L134

134-137 the lines with timer initialization

https://github.com/Jeredian/mks-wifi-plugin/blob/6edac06388a3fadbebf769b08ad3cd5991c75d3a/MKSWifiPlugin/MKSOutputDevice.py#L1068

1068-1070 lines with code for printer reconnecting

https://github.com/Jeredian/mks-wifi-plugin/blob/6edac06388a3fadbebf769b08ad3cd5991c75d3a/MKSWifiPlugin/MKSOutputDevice.py#L174

174 line with socket waiting

So MainThread was blocked when we call self._socket.waitForConnected(2000).

[berberic2]

I know it’s easy to talk big – sorry for that…

Possible no UI „fixes“ would be:
· giving up after 10 failed attempt, or
· after some failes increase interval to one attempt every X minutes.
I would prefer a „connect“ button so.