- Qt 5.15
- Qt Core
- C++ Classes
- QMarginsF
- Qt 5.15.19 Reference Documentation

# QMarginsF Class

The QMarginsF class defines the four margins of a rectangle. More...

Header: | #include <QMarginsF>
qmake: | QT += core
Since: | Qt 5.3

This class was introduced in Qt 5.3.

- List of all members, including inherited members

## Public Functions

| QMarginsF(const QMargins &margins)
| QMarginsF(qreal left, qreal top, qreal right, qreal bottom)
| QMarginsF()
qreal | bottom() const
bool | isNull() const
qreal | left() const
qreal | right() const
void | setBottom(qreal bottom)
void | setLeft(qreal left)
void | setRight(qreal right)
void | setTop(qreal Top)
QMargins | toMargins() const
qreal | top() const
QMarginsF & | operator*=(qreal factor)
QMarginsF & | operator+=(const QMarginsF &margins)
QMarginsF & | operator+=(qreal addend)
QMarginsF & | operator-=(const QMarginsF &margins)
QMarginsF & | operator-=(qreal subtrahend)
QMarginsF & | operator/=(qreal divisor)

## Related Non-Members

bool | operator!=(const QMarginsF &lhs, const QMarginsF &rhs)
QMarginsF | operator*(const QMarginsF &lhs, qreal rhs)
QMarginsF | operator*(qreal lhs, const QMarginsF &rhs)
QMarginsF | operator+(const QMarginsF &lhs, const QMarginsF &rhs)
QMarginsF | operator+(const QMarginsF &lhs, qreal rhs)
QMarginsF | operator+(qreal lhs, const QMarginsF &rhs)
QMarginsF | operator+(const QMarginsF &margins)
QMarginsF | operator-(const QMarginsF &lhs, const QMarginsF &rhs)
QMarginsF | operator-(const QMarginsF &lhs, qreal rhs)
QMarginsF | operator-(const QMarginsF &margins)
QMarginsF | operator/(const QMarginsF &lhs, qreal rhs)
QDataStream & | operator<<(QDataStream &stream, const QMarginsF &m)
bool | operator==(const QMarginsF &lhs, const QMarginsF &rhs)
QDataStream & | operator>>(QDataStream &stream, QMarginsF &m)

## Detailed Description

QMarginsF defines a set of four margins; left, top, right and bottom, that describe the size of the borders surrounding a rectangle.

The isNull() function returns `true` only if all margins are very close to zero.

QMarginsF objects can be streamed as well as compared.

## Member Function Documentation

### QMarginsF::QMarginsF(const QMargins &margins)

Constructs margins copied from the given margins.

### QMarginsF::QMarginsF(qreal left, qreal top, qreal right, qreal bottom)

Constructs margins with the given left, top, right, bottom

See also setLeft(), setRight(), setTop(), and setBottom().

### QMarginsF::QMarginsF()

Constructs a margins object with all margins set to 0.

See also isNull().

### qreal QMarginsF::bottom() const

Returns the bottom margin.

See also setBottom().

### bool QMarginsF::isNull() const

Returns `true` if all margins are very close to 0; otherwise returns false.

See also qFuzzyIsNull.

### qreal QMarginsF::left() const

Returns the left margin.

See also setLeft().

### qreal QMarginsF::right() const

Returns the right margin.

See also setRight().

### void QMarginsF::setBottom(qreal bottom)

Sets the bottom margin to bottom.

See also bottom().

### void QMarginsF::setLeft(qreal left)

Sets the left margin to left.

See also left().

### void QMarginsF::setRight(qreal right)

Sets the right margin to right.

See also right().

### void QMarginsF::setTop(qreal Top)

Sets the Top margin to Top.

See also top().

### QMargins QMarginsF::toMargins() const

Returns an integer based copy of this margins object.

Note that the components in the returned margins will be rounded to the nearest integer.

See also QMarginsF().

### qreal QMarginsF::top() const

Returns the top margin.

See also setTop().

### QMarginsF &QMarginsF::operator*=(qreal factor)

Multiplies each component of this object by factor and returns a reference to it.

See also operator/=().

### QMarginsF &QMarginsF::operator+=(const QMarginsF &margins)

Add each component of margins to the respective component of this object and returns a reference to it.

See also operator-=().

### QMarginsF &QMarginsF::operator+=(qreal addend)

This is an overloaded function.

Adds the addend to each component of this object and returns a reference to it.

See also operator-=().

### QMarginsF &QMarginsF::operator-=(const QMarginsF &margins)

Subtract each component of margins from the respective component of this object and returns a reference to it.

See also operator+=().

### QMarginsF &QMarginsF::operator-=(qreal subtrahend)

This is an overloaded function.

Subtracts the subtrahend from each component of this object and returns a reference to it.

See also operator+=().

### QMarginsF &QMarginsF::operator/=(qreal divisor)

Divides each component of this object by divisor and returns a reference to it.

See also operator*=().

## Related Non-Members

### bool operator!=(const QMarginsF &lhs, const QMarginsF &rhs)

Returns `true` if lhs and rhs are sufficiently different; otherwise returns `false`.

Warning: This function does not check for strict inequality; instead, it uses a fuzzy comparison to compare the margins.

See also qFuzzyCompare.

### QMarginsF operator*(const QMarginsF &lhs, qreal rhs)

This is an overloaded function.

Returns a QMarginsF object that is formed by multiplying each component of the given lhs margins by rhs factor.

See also QMarginsF::operator*=() and QMarginsF::operator/=().

### QMarginsF operator*(qreal lhs, const QMarginsF &rhs)

This is an overloaded function.

Returns a QMarginsF object that is formed by multiplying each component of the given lhs margins by rhs factor.

See also QMarginsF::operator*=() and QMarginsF::operator/=().

### QMarginsF operator+(const QMarginsF &lhs, const QMarginsF &rhs)

Returns a QMarginsF object that is the sum of the given margins, lhs and rhs; each component is added separately.

See also QMarginsF::operator+=() and QMarginsF::operator-=().

### QMarginsF operator+(const QMarginsF &lhs, qreal rhs)

Returns a QMarginsF object that is formed by adding rhs to lhs.

See also QMarginsF::operator+=() and QMarginsF::operator-=().

### QMarginsF operator+(qreal lhs, const QMarginsF &rhs)

Returns a QMarginsF object that is formed by adding lhs to rhs.

See also QMarginsF::operator+=() and QMarginsF::operator-=().

### QMarginsF operator+(const QMarginsF &margins)

Returns a QMargin object that is formed from all components of margins.

### QMarginsF operator-(const QMarginsF &lhs, const QMarginsF &rhs)

Returns a QMarginsF object that is formed by subtracting rhs from lhs; each component is subtracted separately.

See also QMarginsF::operator+=() and QMarginsF::operator-=().

### QMarginsF operator-(const QMarginsF &lhs, qreal rhs)

Returns a QMarginsF object that is formed by subtracting rhs from lhs.

See also QMarginsF::operator+=() and QMarginsF::operator-=().

### QMarginsF operator-(const QMarginsF &margins)

Returns a QMargin object that is formed by negating all components of margins.

### QMarginsF operator/(const QMarginsF &lhs, qreal rhs)

This is an overloaded function.

Returns a QMarginsF object that is formed by dividing the components of the given lhs margins by the given rhs divisor.

See also QMarginsF::operator*=() and QMarginsF::operator/=().

### QDataStream &operator<<(QDataStream &stream, const QMarginsF &m)

Writes margin m to the given stream and returns a reference to the stream.

See also Serializing Qt Data Types.

### bool operator==(const QMarginsF &lhs, const QMarginsF &rhs)

Returns `true` if lhs and rhs are approximately equal; otherwise returns false.

Warning: This function does not check for strict equality; instead, it uses a fuzzy comparison to compare the margins.

See also qFuzzyCompare.

### QDataStream &operator>>(QDataStream &stream, QMarginsF &m)

Reads a margin from the given stream into margin m and returns a reference to the stream.

See also Serializing Qt Data Types.