Help debugging translation failure

[ghutchis]

I've been trying to figure out why translations don't seem to work in my app (and similar code worked in Qt4).

  QLocale currentLocale;
  qDebug() << "Locale: " << currentLocale.name();

This looks good - we see the right LANG show up.

avoTranslator->load(currentLocale, "avogadroapp", "-", translationPath) returns true - so it finds the QM files
app.installTranslator() returns true so the translator is loaded

Nothing in the interface shows up with translation. So I tried:

qDebug() << "Translated: " << app.translate("MainWindow", "&Export");

Nope, no translation.

Again, I just ported our working Qt4 code for Qt 5.12.x.

Now we use .po files and use lconvert and lrelease to generate the *.qm files:
lconvert -locations none $x -o ${x%%.po}.ts
lrelease -compress -removeidentical *.ts

Again, this was the procedure with our working Qt4 app.

I'm not sure where to start. Is there a good breakpoint or method to see why my loaded translations aren't working?

Any ideas on how to debug this would be welcome. (I'm not looking for solutions - just ideas / starting places.)

Thanks in advance!

[sierdzio]

I don't know solution, and I've never worked with .po files, but maybe some of this will help:

• try out different Qt versions. I've recently had a case where translations generated by Qt 5.12.10 were not working, but when Qt 5.12.5 was used all was fine (with absolutely no code changes!)
• make sure you clean up whole build directory to always have a clean compilation. It's easy to get stuck with old .qm file when tweaking code and doing incremental builds
• open the .ts files in Qt Linguist and see if translations are there

[ghutchis]

@sierdzio - thanks. The files are definitely cleaned up. I'll try a different Qt version soon.

As to Linguist - the translations are there and "finished" (green check) so that's good.

Do the .qm files depend on the Qt version that generate them? Like if I generate them on Ubuntu GitHub actions, can I use them on a Mac or Windows system?

[Christian Ehrlicher]

@ghutchis said in Help debugging translation failure:

"MainWindow", "&Export"

Please take a look into the ts files and see if there is really a section MainWindow with the to be translated text &Export

[ghutchis]

@Christian-Ehrlicher I've tried everything, including nullptr, and "" (empty string). (The source code for QTranslate converts nullptr into "".)

The lconvert creates .ts files with no context. So I tried manual translation both with and without context.

I guess one question is if the tr() calls all have context, do they "fall back" to a translation without context? I'm having trouble following that part of the code:
https://code.qt.io/cgit/qt/qtbase.git/tree/src/corelib/kernel/qtranslator.cpp

[Christian Ehrlicher]

@ghutchis said in Help debugging translation failure:

do they "fall back" to a translation without context?

No

[SGaist]

Hi,

Just a wild idea but did you check for difference in sizes between your old and working files and the new ones ?

I would also compare with files generated using the classic workflow.

Using a minimal dummy application might also help find the culprit.

[sierdzio]

@ghutchis said in Help debugging translation failure:

Do the .qm files depend on the Qt version that generate them? Like if I generate them on Ubuntu GitHub actions, can I use them on a Mac or Windows system?

No, the are usually compatible with a very wide range of Qt versions. But as I mentioned in my comment - bugs happen :-)