Discuss: End support for Qt4

[Edward K. Ream]

Qt no longer supports Qt4.

It is not possible to install pyQt4 using pip. On windows, one needs to download an executable installer.  Not sure about linux.

For these and other reasons I am thinking that it is time to end Leo's support for pyQt4.

This decision won't become urgent until I merge the leo-qt6-2 branch into devel, and that might not happen until after Leo 6.4 final.

Your thoughts, please.

Edward

[Edward K. Ream]

On Tuesday, July 13, 2021 at 11:42:19 AM UTC-5 Edward K. Ream wrote:

I am thinking that it is time to end Leo's support for pyQt4.

Belay that. I feel much better after a nap :-)

Imo, there is no reason to inconvenience any Leonista who is presently using pyQt4! Likewise, there is no need to be overly timid about supporting pyQt6.

I'll install pyQt4 and do enough testing to ensure that Leo will be fairly functional. Ditto for pyQt5 and 6. Such testing should take only a few hours.

Tomorrow or Thursday I'll merge ekr-qt6-2 into devel. We can then all shake down the new code. There is no reason to delay wider testing!

Most bugs are likely to be misspellings, easily fixed, in leoQt4.py, leoQt5.py or leoQt6.py. I'll release 4.6b1 only after at least three days have passed since the last bug has been fixed against the new qt code. That should be safe enough.

Comments still welcome and encouraged.

Edward

[Edward K. Ream]

On Tuesday, July 13, 2021 at 3:31:42 PM UTC-5 Edward K. Ream wrote:

I am thinking that it is time to end Leo's support for pyQt4.

Belay that. I feel much better after a nap :-)

Well, it appears that it really is time to discontinue support for pyQt4. Indeed, this page lists has pre-built versions only for python 3.7 and earlier.  I test Leo only with Python 3.6 and Python 3.9. Note also that pyQt4 is no longer supported, and several pages strongly discourage using pyQt4.

It's very easy to install pyQt5 or pyQt6, so I don't think many people (anyone??) will be put out if we discontinue support for pyQt4.  In Leo's code it's easy to discontinue support for pyQt4: just don't import it in leoQt.py

In case I'm wrong, I'll leave leoQt4.py in place for now, but unless I hear howls of protest leoQt4.py will not be part of Leo 6.4 final.

Edward