Constructs a mouse event object.
The type parameter must be QEvent::MouseButtonPress, QEvent::MouseButtonRelease, QEvent::MouseButtonDblClick, or QEvent::MouseMove.
The pos is the mouse cursor's position relative to the receiving widget. The cursor's position in global coordinates is specified by globalPos. The button that caused the event is given as a value from the Qt::MouseButton enum. If the event type is MouseMove, the appropriate button for this event is Qt::NoButton. buttons is the state of all buttons at the time of the event, modifiers the state of all keyboard modifiers.