QHelpEvent Class

The QHelpEvent class asks a widget for the help it has at a position, such as a tool tip. More…

Header	`#include <QtGui/qevent.h>`
CMake	`target_link_libraries(app PRIVATE Nt::Gui)`
Module	Nt GUI C++ Classes
Inherits	QEvent

List of all members, including inherited members

Public Functions

	QHelpEvent(Type type, const QPoint &pos, const QPoint &globalPos)
int	x() const
int	y() const
int	globalX() const
int	globalY() const
QPoint	pos() const
QPoint	globalPos() const

Reimplemented Public Functions

QHelpEvent *

clone() const

Detailed Description

A window sends a QHelpEvent of the type QEvent::ToolTip to the widget under the mouse when the mouse has rested there for a moment. A widget that has something to show for the position shows it and accepts the event; one that does not ignores it, and the event goes on to its parent. Reimplement QWidget::event() to show a tool tip that depends on the position, as a table does for its cells:

bool MyWidget::event(QEvent *event)
{
    if (event->type() == QEvent::ToolTip) {
        auto *help = static_cast<QHelpEvent *>(event);
        QToolTip::showText(help->globalPos(), describe(help->pos()), this);
        return true;
    }
    return QWidget::event(event);
}

See also QEvent and QMouseEvent.

Differences from Qt

There is no WhatsThis event type, and the position is a QPoint.

Member Function Documentation

QHelpEvent::QHelpEvent(Type type, const QPoint &pos, const QPoint &globalPos)

Constructs a help event of the given type for a mouse at pos in the widget and globalPos on the screen.

[override] QHelpEvent * QHelpEvent::clone() const

Reimplements QEvent::clone().

QPoint QHelpEvent::globalPos() const

Returns the position on the screen.

int QHelpEvent::globalX() const

Returns the x coordinate of the position on the screen.

int QHelpEvent::globalY() const

Returns the y coordinate of the position on the screen.

QPoint QHelpEvent::pos() const

Returns the position in the widget.

int QHelpEvent::x() const

Returns the x coordinate of the position in the widget.

int QHelpEvent::y() const

Returns the y coordinate of the position in the widget.