QSizeF Class

Member Function Documentation

[since 5.14] QSizeF QSizeF::shrunkBy(QMarginsF margins) const

Returns the size that results from shrinking this size by margins.

This function was introduced in Qt 5.14.

See also grownBy().

[since 5.14] QSizeF QSizeF::grownBy(QMarginsF margins) const

Returns the size that results from growing this size by margins.

This function was introduced in Qt 5.14.

See also shrunkBy().

QSizeF::QSizeF(qreal width, qreal height)

Constructs a size with the given finite width and height.

QSizeF::QSizeF(const QSize &size)

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

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

QSizeF::QSizeF()

Constructs an invalid size.

See also isValid().

QSizeF QSizeF::boundedTo(const QSizeF &otherSize) const

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

See also expandedTo() and scale().

QSizeF QSizeF::expandedTo(const QSizeF &otherSize) const

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

See also boundedTo() and scale().

[static, since 5.8] QSizeF QSizeF::fromCGSize(CGSize size)

Creates a QRectF from size.

This function was introduced in Qt 5.8.

See also toCGSize().

qreal QSizeF::height() const

Returns the height.

See also width() and setHeight().

bool QSizeF::isEmpty() const

Returns true if either of the width and 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 0.0 (ignoring the sign); otherwise returns false.

See also isValid() and isEmpty().

bool QSizeF::isValid() const

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

See also isNull() and isEmpty().

qreal &QSizeF::rheight()

Returns a reference to the height.

Using a reference makes it possible to manipulate the height directly. For example:

QSizeF size(100, 10.2);
size.rheight() += 5.5;

// size becomes (100,15.7)

See also rwidth() and setHeight().

qreal &QSizeF::rwidth()

Returns a reference to the width.

Using a reference makes it possible to manipulate the width directly. For example:

QSizeF size(100.3, 10);
size.rwidth() += 20.5;

 // size becomes (120.8,10)

See also rheight() and setWidth().

void QSizeF::scale(qreal width, qreal height, Qt::AspectRatioMode mode)

Scales the size to a rectangle with the given width and height, according to the specified mode.

• If mode is Qt::IgnoreAspectRatio, the size is set to (width, height).
• If mode is Qt::KeepAspectRatio, the current size is scaled to a rectangle as large as possible inside (width, height), preserving the aspect ratio.
• If mode is Qt::KeepAspectRatioByExpanding, the current size is scaled to a rectangle as small as possible outside (width, height), preserving the aspect ratio.

Example:

QSizeF t1(10, 12);
t1.scale(60, 60, Qt::IgnoreAspectRatio);
// t1 is (60, 60)

QSizeF t2(10, 12);
t2.scale(60, 60, Qt::KeepAspectRatio);
// t2 is (50, 60)

QSizeF t3(10, 12);
t3.scale(60, 60, Qt::KeepAspectRatioByExpanding);
// t3 is (60, 72)

See also setWidth(), setHeight(), and scaled().

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

This is an overloaded function.

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

[since 5.0] QSizeF QSizeF::scaled(qreal width, qreal height, Qt::AspectRatioMode mode) const

Returns a size scaled to a rectangle with the given width and height, according to the specified mode.

This function was introduced in Qt 5.0.

See also scale().

[since 5.0] QSizeF QSizeF::scaled(const QSizeF &s, Qt::AspectRatioMode mode) const

This is an overloaded function.

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

This function was introduced in Qt 5.0.

void QSizeF::setHeight(qreal height)

Sets the height to the given finite height.

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

void QSizeF::setWidth(qreal width)

Sets the width to the given finite width.

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

[since 5.8] CGSize QSizeF::toCGSize() const

Creates a CGSize from a QSizeF.

This function was introduced in Qt 5.8.

See also fromCGSize().

QSize QSizeF::toSize() const

Returns an integer based copy of this size.

Note that the coordinates in the returned size will be rounded to the nearest integer.

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

void QSizeF::transpose()

Swaps the width and height values.

See also setWidth(), setHeight(), and transposed().

[since 5.0] QSizeF QSizeF::transposed() const

Returns the size with width and height values swapped.

This function was introduced in Qt 5.0.

See also transpose().

qreal QSizeF::width() const

Returns the width.

See also height() and setWidth().

QSizeF &QSizeF::operator*=(qreal factor)

This is an overloaded function.

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

See also scale().

QSizeF &QSizeF::operator+=(const QSizeF &size)

Adds the given size to this size and returns a reference to this size. For example:

QSizeF s( 3, 7);
QSizeF r(-1, 4);
s += r;

// s becomes (2,11)

QSizeF &QSizeF::operator-=(const QSizeF &size)

Subtracts the given size from this size and returns a reference to this size. For example:

QSizeF s( 3, 7);
QSizeF r(-1, 4);
s -= r;

// s becomes (4,3)

QSizeF &QSizeF::operator/=(qreal divisor)

This is an overloaded function.

Divides both the width and height by the given divisor and returns a reference to the size. The divisor must not be either zero or NaN.

See also scale().