Qt question: How do signals and slots work?
QtCore.SIGNAL() and QtCore.SLOT() macros allow Python to interface with Qt signal and slot delivery mechanisms. This is the old way of using signals and slots.
Kiến trúc UNIX/LINUX
Step 4 – Signals and Slots. The class declaration looks like this when the slot and signal have been added. class ValueObject : public QObject. {. Q_OBJECT.
Signals and slots - Wikipedia
I mean you can connect many slots to a signal, and if a slot is deleted the signal will know. Basically just saying those things are important to any library you want to use, and make implementation of a GOOD signal/slot mechanism non-trivial.
Definition of signal slope
In this example, the SIGNAL() and SLOT() macros are used to specify the signal (dataReady) and slot (onDataReady) to connect.