The QStatusBar class provides a horizontal bar suitable for presenting status information.| doc.qt.io
The QPaintEvent class contains event parameters for paint events.| doc.qt.io
The QWidget class is the base class of all user interface objects.| doc.qt.io
The QEvent class is the base class of all event classes. Event objects contain event parameters.| doc.qt.io
The QString class provides a Unicode character string.| doc.qt.io