Different languages in different parts of application

Question

I have a multilingual Qt application, where I have the following problem

1. The bulk of the UI should be translated to match the language of the system locale
2. The application can also print various forms. The language of these forms should be independently selectable from the UI language (the forms will be handed over to people who often don't speak the local language)
3. If possible, it would be nice to have the same capability as the previous point also for a dialog in the application.

In what way can I achieve this? All the examples I found deal with translating the entire application, but in my case, I need two independent translations (although possibly to the same language).

Would I need to replicate the fall-back mechanisms of QApplication::translate myself and use QTranslator::translate directly, or is there a more convenient way?

Answer 1

Let's assume you need one translation for whole app, and another for a dialog. What you need to do is to create two qm files: one, which contains translations of everything, except this dialog, and one, which contains translations only for this dialog. Now you can load/unload this qm files separately.

I guess you know how to change translation dynamically.

Update from comment:

To create separate qm files you could put all main sources in one directory, and all dialog sources into another and call lupdate -no-obsolete -recursive ../src/Form -ts Form_ru.ts, where ../src/Form is dialogs directory. Or even call lupdate -no-obsolete ../src/Form.ui ../src/Form.cpp ../src/Form.h -ts Form_ru.ts on files.

The result script would be something like this:

lupdate -no-obsolete -recursive ../test.pro -ts test_ru.ts
lupdate -no-obsolete ../Form.ui ../Form.cpp ../Form.h -ts Form_ru.ts

Answer 2

As the QTranslator class has a virtual function for translate. You could inherit from QTranslator and overload the translate function to return the language string for each locale you want, depending on a flag you set in your inherited class.

You then set the flag to the locale you want to use just before creating the page for printing and then set it back after that.