Techdraw: finish Qt6 port

[wwmayer]

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[chennes]

Was this the last thing that we were waiting on for full Qt6 support?

[freecadci]

for feature branch PR_9104. Pipeline 820522117 was triggered at 372f578. All CI branches and pipelines.

[wwmayer]

Yes, I think so.

However, we still have tons of slot functions of this form on_objectname_signalname that are automatically connected with QMetaObject::connectSlotsByName. Since several signals have been renamed in Qt6 some automatic connections may fail.

[wwmayer]

BTW, the algorithm for Qt6 can be easily tested with Qt5. Therefore replace #if QT_VERSION < QT_VERSION_CHECK(6,0,0) with #if 0 in XMLQuery.cpp. When creating a TD page you will see the green bullets where you can change the editable fields.

Now if you comment out the line processElements inside processItems you will realize that the green bullets are missing.

[chennes]

However, we still have tons of slot functions of this form on_objectname_signalname that are automatically connected with QMetaObject::connectSlotsByName. Since several signals have been renamed in Qt6 some automatic connections may fail.

Should we be eliminating the automatic connections and doing it manually?

[wwmayer]

Should we be eliminating the automatic connections and doing it manually?

This is what clazy recommends. I don't have a commit right now that shows the warning but you have already seen it for sure that clazy says that the automatic connections are error-prone. IMO, it's similar to the old-style connect with SIGNAL and SLOT which has raised many issues with the Qt6 port.

So, as a long-term goal we should migrate to the manual connection but this is not of high priority.

[wwmayer]

@WandererFan please have a look and merge if all is OK.

[WandererFan]

This works fine with Qt5. I don't have Qt6 installed yet.

Thanks for handling this.