before I did that, I moved your folder to /home/pi/
then I again created a new project like before, now also named quit_wiringPi in my programs subfolder.
build => again correctly an empty main window as before, as expected.
Unfortunately I cannot access this forum on my Pi, it's a torture to start the browser - so I can't c+p anything from qt here (e.g. from "Compile Output" window).
Now I copied your mainwindow.cpp + .h files and patched the pro file.
build => again an empty main window as before, unexpectedly.
trying to load mainwindow.ui threw an error (file does not exist or I don't have the rights)
=> marked all files and changed modify rights for owner -> everyone)
now I can load the ui file, but it's blank, no buttons, no labels.
then I renamed mainwindow.ui to mainwindow.ui.void
and copied your mainwindow.ui into this folder, changed rights,
loaded the project,
mainwindow.ui now provides buttons and labels.
but after build => still an empty window
then I reloaded your files from your directory, but surpringly now also building an empty main window, whilst the log file now referred to MY directory instead
now I again completely overwrote my files in my folder with ALL of your files,
again changed all rights for modify to everyone,
again reloaded your project
build => now main window appears, but AGAIN EMPTY.
then I checked the other folder build-quit_wiringPi-....
and surpringly now the executable is called
(like my old project before, not quit_wiringPi as intended)
and when starting THAT directly, then your correct new main window appears...
now all buttons show up and work correctly, both for the LED and for the switch!!!
again restarting the project out of the qtcreator (green run button)
=> also fine now, all buttons and labels now work !
=> in the log message the target is called quit_btn, not quit_wiringPi though
but what a mess about the file names!
how can that be corrected to have an executable correctly named like the project?
what also makes me wonder:
in your mainwindow.ui I only see the buttons and the constant label "pin24",
but the output labels for pin23-state and pin24-state don't show up:
WHY? How can I also see that in my form design (e.g. to change size, position,...)?
an extra warning in the output log:
libEGL warning: DRI2: failed to authenticate
GREAT WORK! Thank you very much for your efforts for now!