How to tranlaste #define and text from file

What does QLibraryInfo have to do with this??? You are supposed to install a translator on your application using Qt's message catalog that resides in the translations subdirectory of your Qt installation.

and how do it?

The same as you do it with any other translator -- you load the message catalog and install the translator on the application.

thank this works, but there are only few languages. how add my language?

TS files for Qt are available. You can provide your own translations using Linguist or search the web if an external catalog for your language is available.