Hello Marcel
Thanks for your reply. I have tried it, but I could not manage to solve the problem.
Here is the code:

Qt Code:
  1. completer = new QCompleter (keys, this);
  2. completer->setCaseSensitivity (QCompleter::CaseSensitive);
  3. completer->setCompletionMode (QCompleter::PopupCompletion);
  4. LineEdit->setInputMask ("NNNNN-NNNNN-NNNNN-NNNNN;_");
  5. LineEdit->setCompleter (completer);
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The keys variable contains a list of serial keys that are of the form specified as the mask. Unfortunately, the completer does not work. Any suggestions?

Best Regards