Can Qt signals be public or private? Can I create internal signals, which are seen only inside the class?
Update: I have a class with some internal signals. How can I make those signals invisible for other classes (encapsulation & information hiding)?
Answer
No. Signals cannot be public or private. Qt signals are protected class methods.
"signals" keyword is defined in qobjectdefs.h (line 69 as for Qt 4.6.1):
# define signals protected
UPDATE: signals are only protected upto and including all minor versions of Qt 4. From Qt 5.0 onwards they are public. See https://stackoverflow.com/a/19130831.