Using a Timer in Qt

For using the timer in Qt, the class QTimer is intended. First, you need to set the time after which it will trigger. You also need to define a slot that will handle the signal emitted when the timer overflows. Thus, a mandatory condition for using QTimer is the ability to use signals and slots, which means that the class that uses the timer must be a descendant of QObject. Let's create a simple clock as an example.