I tried to extend okular to save PDF-Print-Options (wish #463732). All works well so far, I added a new item in the configuration dialog and the new variable "PageScaleMode" is written to and read from "okularpartrc", but I am not able to assign the value of "Okular::Settings::pageScaleMode" to "m_scaleMode->setCurrentIndex" in module "generator_pdf.cpp".

Compilation is successful, but it crashes on runtime after opening the print dialog. Message on terminal is "you need to call Settings::instance before using".

I am not too familiar with C++ coding and it is my first try to extend an application. I inspected already the other modules of the project where the developers used "Okular::Settings::" in a similar & working way, but I could not find out so far, where the instance has been set for a proper usage.

Can anyone tell me what I missed, or guide me to a code example of the okular project where I can see how to get right access to "Okular::Settings::"? Thank you in advance for your support.