QSizeF Class

The QSizeF class defines the size of a two-dimensional object using floating point precision. More…

List of all members, including inherited members

Public Functions

Detailed Description

A size is specified by a width() and a height(), both stored as double. A default-constructed size is invalid, with a width and height of -1. Use QSize for integer dimensions.

Equality comparison is fuzzy: two dimensions are considered equal if they are equal within the precision of double.

See also QSize, QPointF and QRectF.

Differences from Qt

Member Function Documentation

[constexpr] QSizeF::QSizeF()

Constructs an invalid size with a width and height of -1.0.

See also isValid().

[constexpr] QSizeF::QSizeF(const QSize &s)

Constructs a size with floating point accuracy from the given integer size s.

See also toSize() and QSize::toSizeF().

[constexpr] QSizeF::QSizeF(double w, double h)

Constructs a size with the given w and h.

[constexpr] QSizeF QSizeF::boundedTo(const QSizeF &o) const

Returns a size holding the minimum width and height of this size and the o size.

See also expandedTo().

[constexpr] QSizeF QSizeF::expandedTo(const QSizeF &o) const

Returns a size holding the maximum width and height of this size and the o size.

See also boundedTo().

[constexpr] QSizeF QSizeF::grownBy(const QMarginsF &m) const

Returns the size grown by the margins m.

This function was introduced in 5.14.

See also shrunkBy().

[constexpr] double QSizeF::height() const

Returns the height.

See also width(), setHeight() and rheight().

[constexpr] bool QSizeF::isEmpty() const

Returns true if the width or the height is less than or equal to 0; otherwise returns false.

See also isNull() and isValid().

bool QSizeF::isNull() const

Returns true if both the width and height are fuzzily equal to 0; otherwise returns false.

See also isEmpty() and isValid().

[constexpr] bool QSizeF::isValid() const

Returns true if both the width and the height are equal to or greater than 0; otherwise returns false.

See also isNull() and isEmpty().

[constexpr] QSizeF & QSizeF::operator*=(double f)

Multiplies both the width and height by the given factor f and returns a reference to this size.

[constexpr] QSizeF & QSizeF::operator+=(const QSizeF &s)

Adds the given s to this size and returns a reference to this size.

[constexpr] QSizeF & QSizeF::operator-=(const QSizeF &s)

Subtracts the given s from this size and returns a reference to this size.

[constexpr] QSizeF & QSizeF::operator/=(double d)

Divides both the width and height by the given divisor d and returns a reference to this size.

[constexpr] double & QSizeF::rheight()

Returns a reference to the height, allowing it to be modified directly.

See also height() and setHeight().

[constexpr] double & QSizeF::rwidth()

Returns a reference to the width, allowing it to be modified directly.

See also width() and setWidth().

void QSizeF::scale(const QSizeF &s, Qt::AspectRatioMode mode)

Scales this size to a rectangle with the given size s, according to the given mode.

See also scaled().

void QSizeF::scale(double w, double h, Qt::AspectRatioMode mode)

This is an overloaded function.

Scales the size to a rectangle of width w and height h, as mode says.

QSizeF QSizeF::scaled(const QSizeF &s, Qt::AspectRatioMode mode) const

Returns this size scaled to a rectangle with the given size s, according to the given mode.

If mode is Qt::IgnoreAspectRatio, or this size has a zero width or height, s is returned unchanged. With Qt::KeepAspectRatio the result fits inside s; with Qt::KeepAspectRatioByExpanding it covers s.

See also scale().

QSizeF QSizeF::scaled(double w, double h, Qt::AspectRatioMode mode) const

This is an overloaded function.

Returns the size scaled to a rectangle of width w and height h, as mode says.

[constexpr] void QSizeF::setHeight(double h)

Sets the height to the given h.

See also height() and setWidth().

[constexpr] void QSizeF::setWidth(double w)

Sets the width to the given w.

See also width() and setHeight().

[constexpr] QSizeF QSizeF::shrunkBy(const QMarginsF &m) const

Returns the size shrunk by the margins m.

This function was introduced in 5.14.

See also grownBy().

QSize QSizeF::toSize() const

Returns a QSize with the width and height rounded to the nearest integer.

See also QSize::toSizeF().

[constexpr] void QSizeF::transpose()

Swaps the width and height values.

See also transposed().

[constexpr] QSizeF QSizeF::transposed() const

Returns a size with the width and height values swapped.

See also transpose().

[constexpr] double QSizeF::width() const

Returns the width.

See also height(), setWidth() and rwidth().