内容

• 特性
• 公共函数
• 详细描述

QGeoCircle Class

The QGeoCircle class defines a circular geographic area. 更多...

头：	#include <QGeoCircle>
CMake:	find_package(Qt6 COMPONENTS Positioning REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Positioning)
qmake:	QT += positioning
Since:	Qt 5.2
继承：	QGeoShape

• 所有成员列表，包括继承成员

特性

• center : QGeoCoordinate
• radius : qreal

公共函数

	QGeoCircle (const QGeoShape & other )
	QGeoCircle (const QGeoCircle & other )
	QGeoCircle (const QGeoCoordinate & center , qreal radius = -1.0)
	QGeoCircle ()
QGeoCircle &	operator= (const QGeoCircle & other )
	~QGeoCircle ()
QGeoCoordinate	center () const
void	extendCircle (const QGeoCoordinate & coordinate )
qreal	radius () const
void	setCenter (const QGeoCoordinate & center )
void	setRadius (qreal radius )
QString	toString () const
void	translate (double degreesLatitude , double degreesLongitude )
QGeoCircle	translated (double degreesLatitude , double degreesLongitude ) const

详细描述

The circle is defined in terms of a QGeoCoordinate which specifies the center of the circle and a qreal which specifies the radius of the circle in meters.

The circle is considered invalid if the center coordinate is invalid or if the radius is less than zero.

This class is a Q_GADGET since Qt 5.5. It can be directly used from C++ and QML .

特性文档编制

[since 5.5] center : QGeoCoordinate

This property holds the center coordinate for the geo circle.

The circle is considered invalid if this property contains an invalid coordinate.

A default constructed QGeoCircle uses an invalid QGeoCoordinate as center.

While this property is introduced in Qt 5.5, the related accessor functions exist since the first version of this class.

该特性在 Qt 5.5 引入。

访问函数：

QGeoCoordinate	center () const
void	setCenter (const QGeoCoordinate & center )

[since 5.5] radius : qreal

This property holds the circle radius in meters.

The circle is considered invalid if this property is negative.

By default, the radius is initialized with -1 .

While this property is introduced in Qt 5.5, the related accessor functions exist since the first version of this class.

该特性在 Qt 5.5 引入。

访问函数：

qreal	radius () const
void	setRadius (qreal radius )

成员函数文档编制

QGeoCircle:: QGeoCircle (const QGeoShape & other )

Constructs a new geo circle from the contents of other .

QGeoCircle:: QGeoCircle (const QGeoCircle & other )

Constructs a new geo circle from the contents of other .

QGeoCircle:: QGeoCircle (const QGeoCoordinate & center , qreal radius = -1.0)

Constructs a new geo circle centered at center and with a radius of radius meters.

QGeoCircle:: QGeoCircle ()

Constructs a new, invalid geo circle.

QGeoCircle &QGeoCircle:: operator= (const QGeoCircle & other )

赋值 other to this geo circle and returns a reference to this geo circle.

QGeoCircle:: ~QGeoCircle ()

Destroys this geo circle.

QGeoCoordinate QGeoCircle:: center () const

Returns the center coordinate of this geo circle. Equivalent to QGeoShape::center ().

注意： getter 函数对于特性 center .

另请参阅 setCenter ().

[invokable, since 5.9] void QGeoCircle:: extendCircle (const QGeoCoordinate & coordinate )

Extends the geo circle to also cover the coordinate coordinate

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

该函数在 Qt 5.9 引入。

qreal QGeoCircle:: radius () const

Returns the radius in meters of this geo circle.

注意： getter 函数对于特性 radius .

另请参阅 setRadius ().

void QGeoCircle:: setCenter (const QGeoCoordinate & center )

Sets the center coordinate of this geo circle to center .

注意： setter 函数对于特性 center .

另请参阅 center ().

void QGeoCircle:: setRadius ( qreal radius )

Sets the radius in meters of this geo circle to radius .

注意： setter 函数对于特性 radius .

另请参阅 radius ().

[invokable, since 5.5] QString QGeoCircle:: toString () const

Returns the geo circle properties as a string.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

该函数在 Qt 5.5 引入。

[invokable] void QGeoCircle:: translate ( double degreesLatitude , double degreesLongitude )

Translates this geo circle by degreesLatitude northwards and degreesLongitude eastwards.

Negative values of degreesLatitude and degreesLongitude correspond to southward and westward translation respectively.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

[invokable] QGeoCircle QGeoCircle:: translated ( double degreesLatitude , double degreesLongitude ) const

Returns a copy of this geo circle translated by degreesLatitude northwards and degreesLongitude eastwards.

Negative values of degreesLatitude and degreesLongitude correspond to southward and westward translation respectively.

注意： 此函数可以被援引，通过元对象系统和从 QML。见 Q_INVOKABLE .

另请参阅 translate ().