QFont Class

The QFont class specifies a font used for drawing text. More…

Header	`#include <QFont>`
CMake	`target_link_libraries(app PRIVATE Nt::Gui)`
Module	Nt GUI C++ Classes

List of all members, including inherited members

Public Types

enum

Weight

Public Functions

	QFont()
	QFont(const QString &family, int pointSize = -1, int weight = -1, bool italic = false)
QString	family() const
void	setFamily(const QString &family)
int	pointSize() const
void	setPointSize(int pointSize)
qreal	pointSizeF() const
void	setPointSizeF(qreal pointSize)
int	pixelSize() const
void	setPixelSize(int pixelSize)
Weight	weight() const
void	setWeight(Weight weight)
bool	bold() const
void	setBold(bool enable)
bool	italic() const
void	setItalic(bool enable)

Detailed Description

A font has a family, a size, a weight and an italic flag. Nt looks the font up with fontconfig when text is drawn or measured, so any installed family works, and a family that is not installed gets the closest match:

QFont font("Noto Sans", 12);
font.setBold(true);
QPainter painter(&image);
painter.setFont(font);
painter.drawText(10, 30, "Hello");

Sizes are in points, converted to pixels at 96 dots per inch, or in pixels with setPixelSize().

Differences from Qt

There is no setStyleHint(), setStretch(), underline, strike-out, letter or word spacing, hinting preference or resolve(). A QFont is a plain value; there is no font database, so QFontDatabase is missing and the available families cannot be listed. The font is not found until it is used.

Member Type Documentation

enum QFont::Weight

This enum gives the weight of a font, using the OpenType values.

Constant	Description
`QFont::Thin`	100.
`QFont::ExtraLight`	200.
`QFont::Light`	300.
`QFont::Normal`	400.
`QFont::Medium`	500.
`QFont::DemiBold`	600.
`QFont::Bold`	700.
`QFont::ExtraBold`	800.
`QFont::Black`	900.

Member Function Documentation

QFont::QFont()

Constructs a font that is a copy of the application font, which is the one QGuiApplication::setFont() set, and otherwise "Sans Serif" at 10 points.

See also QGuiApplication::font().

[explicit] QFont::QFont(const QString &family, int pointSize = -1, int weight = -1, bool italic = false)

Constructs a font of the given family, pointSize, weight and italic flag. A negative pointSize leaves the size at the default. The weight is a QFont::Weight value, or a Qt 5 style value from 0 to 99 (50 is normal and 75 bold); -1 stands for Normal.

bool QFont::bold() const

Returns true if the weight is Bold or heavier.

See also setBold().

QString QFont::family() const

Returns the family name.

See also setFamily().

bool QFont::italic() const

Returns true if the font is italic.

See also setItalic().

int QFont::pixelSize() const

Returns the size in pixels, or -1 if the size is in points.

See also setPixelSize().

int QFont::pointSize() const

Returns the size in points, rounded, or -1 if the size is in pixels.

See also pointSizeF() and setPointSize().

qreal QFont::pointSizeF() const

Returns the size in points, or -1 if the size is in pixels.

See also setPointSizeF().

void QFont::setBold(bool enable)

Sets the weight to Bold if enable is true, and to Normal otherwise.

See also bold().

void QFont::setFamily(const QString &family)

Sets the family name to family. An empty name or "Sans Serif" stands for the default sans-serif font.

See also family().

void QFont::setItalic(bool enable)

Makes the font italic if enable is true.

See also italic().

void QFont::setPixelSize(int pixelSize)

Sets the size to pixelSize pixels. The size in points is forgotten.

See also pixelSize().

void QFont::setPointSize(int pointSize)

Sets the size to pointSize points. The size in pixels is forgotten.

See also pointSize().

void QFont::setPointSizeF(qreal pointSize)

Sets the size to pointSize points. The size in pixels is forgotten.

See also pointSizeF().

void QFont::setWeight(Weight weight)

Sets the weight to weight.

See also weight().

Weight QFont::weight() const

Returns the weight.

See also setWeight().