I want to make (or at least know If this is even possible) text that appears in QDoubleSpinBox to be unselectable. Right now, it looks like this:
I have managed to make it so that the QDoubleSpinBox can't be focused with setFocusPolicy(Qt::NoFocus). But this doesn't apply to the text in it.

You can make the text unselectable by calling
setEnabled(false). But it will disable the whole QWidget (disable keyboard and mouse events). So, you should be more precise about what you want to disable and what do you want to keep enabled.