A class which controls a value within an interval. Más...

#include <qwt_double_range.h>

Diagrama de herencias de QwtDoubleRange

Métodos públicos
	QwtDoubleRange ()
virtual	~QwtDoubleRange ()
	Destroys the QwtDoubleRange.
void	setRange (double vmin, double vmax, double vstep=0.0, int pagesize=1)
	Specify range and step size.
void	setValid (bool)
	Set the value to be valid/invalid.
bool	isValid () const
	Indicates if the value is valid.
virtual void	setValue (double)
	Set a new value without adjusting to the step raster.
double	value () const
	Returns the current value.
void	setPeriodic (bool tf)
	Make the range periodic.
bool	periodic () const
	Returns true if the range is periodic.
void	setStep (double)
	Change the step raster.
double	step () const
double	maxValue () const
	Returns the value of the second border of the range.
double	minValue () const
	Returns the value at the first border of the range.
int	pageSize () const
	Returns the page size in steps.
virtual void	incValue (int)
	Increment the value by a specified number of steps.
virtual void	incPages (int)
	Increment the value by a specified number of pages.
virtual void	fitValue (double)
	Adjust the value to the closest point in the step raster.
Métodos protegidos
double	exactValue () const
	Returns the exact value.
double	exactPrevValue () const
	Returns the exact previous value.
double	prevValue () const
	Returns the previous value.
virtual void	valueChange ()
	Notify a change of value.
virtual void	stepChange ()
	Notify a change of the step size.
virtual void	rangeChange ()
	Notify a change of the range.

Descripción detallada

A class which controls a value within an interval.

This class is useful as a base class or a member for sliders. It represents an interval of type double within which a value can be moved. The value can be either an arbitrary point inside the interval (see QwtDoubleRange::setValue), or it can be fitted into a step raster (see QwtDoubleRange::fitValue and QwtDoubleRange::incValue).

As a special case, a QwtDoubleRange can be periodic, which means that a value outside the interval will be mapped to a value inside the interval when QwtDoubleRange::setValue(), QwtDoubleRange::fitValue(), QwtDoubleRange::incValue() or QwtDoubleRange::incPages() are called.

Documentación del constructor y destructor

QwtDoubleRange::QwtDoubleRange ( )

The range is initialized to [0.0, 100.0], the step size to 1.0, and the value to 0.0.

QwtDoubleRange::~QwtDoubleRange ( ) [virtual]

Destroys the QwtDoubleRange.

Documentación de las funciones miembro

double QwtDoubleRange::exactPrevValue ( ) const [protected]

Returns the exact previous value.

double QwtDoubleRange::exactValue ( ) const [protected]

Returns the exact value.

The exact value is the value which QwtDoubleRange::value would return if the value were not adjusted to the step raster. It differs from the current value only if QwtDoubleRange::fitValue or QwtDoubleRange::incValue have been used before. This function is intended for internal use in derived classes.

void QwtDoubleRange::fitValue ( double x ) [virtual]

Adjust the value to the closest point in the step raster.

Parámetros:

x value

Atención:

The value is clipped when it lies outside the range. When the range is QwtDoubleRange::periodic, it will be mapped to a point in the interval such that

new value := x + n * (max. value - min. value)

with an integer number n.

Reimplementado en QwtAbstractSlider.

void QwtDoubleRange::incPages ( int nPages ) [virtual]

Increment the value by a specified number of pages.

Parámetros:

nPages Number of pages to increment. A negative number decrements the value.

Atención:: The Page size is specified in the constructor.

void QwtDoubleRange::incValue ( int nSteps ) [virtual]

Increment the value by a specified number of steps.

Parámetros:

nSteps Number of steps to increment

Atención:: As a result of this operation, the new value will always be adjusted to the step raster.

Reimplementado en QwtAbstractSlider.

bool QwtDoubleRange::isValid ( void ) const

Indicates if the value is valid.

Reimplementado en QwtAbstractSlider.

double QwtDoubleRange::maxValue ( ) const

Returns the value of the second border of the range.

maxValue returns the value which has been specified as the second parameter in QwtDoubleRange::setRange.

Ver también:: QwtDoubleRange::setRange()

double QwtDoubleRange::minValue ( ) const

Returns the value at the first border of the range.

minValue returns the value which has been specified as the first parameter in setRange().

Ver también:: QwtDoubleRange::setRange()

int QwtDoubleRange::pageSize ( ) const

Returns the page size in steps.

bool QwtDoubleRange::periodic ( ) const

Returns true if the range is periodic.

Ver también:: QwtDoubleRange::setPeriodic()

double QwtDoubleRange::prevValue ( ) const [protected]

Returns the previous value.

void QwtDoubleRange::rangeChange ( ) [protected, virtual]

Notify a change of the range.

This virtual function is called whenever the range changes. The default implementation does nothing.

Reimplementado en QwtCounter, QwtDial y QwtSlider.

void QwtDoubleRange::setPeriodic ( bool tf )

Make the range periodic.

When the range is periodic, the value will be set to a point inside the interval such that

point = value + n * width

if the user tries to set a new value which is outside the range. If the range is nonperiodic (the default), values outside the range will be clipped.

Parámetros:

tf	true for a periodic range

void QwtDoubleRange::setRange	(	double	vmin,
		double	vmax,
		double	vstep = `0.0`,
		int	pageSize = `1`
	)

Specify range and step size.

Parámetros:

vmin	lower boundary of the interval
vmax	higher boundary of the interval
vstep	step width
pageSize	page size in steps

Atención:

A change of the range changes the value if it lies outside the new range. The current value will *not* be adjusted to the new step raster.
vmax < vmin is allowed.
If the step size is left out or set to zero, it will be set to 1/100 of the interval length.
If the step size has an absurd value, it will be corrected to a better one.

void QwtDoubleRange::setStep ( double vstep )

Change the step raster.

Parámetros:

vstep new step width

Atención:: The value will not be adjusted to the new step raster.

Reimplementado en QwtCounter.

void QwtDoubleRange::setValid ( bool isValid )

Set the value to be valid/invalid.

Reimplementado en QwtAbstractSlider.

void QwtDoubleRange::setValue ( double x ) [virtual]

Set a new value without adjusting to the step raster.

Parámetros:

x new value

Atención:

The value is clipped when it lies outside the range. When the range is QwtDoubleRange::periodic, it will be mapped to a point in the interval such that

new value := x + n * (max. value - min. value)

with an integer number n.

Reimplementado en QwtAbstractSlider y QwtCounter.

double QwtDoubleRange::step ( ) const

Devuelve:: the step size

Ver también:: QwtDoubleRange::setStep, QwtDoubleRange::setRange

Reimplementado en QwtCounter.

void QwtDoubleRange::stepChange ( ) [protected, virtual]

Notify a change of the step size.

This virtual function is called whenever the step size changes. The default implementation does nothing.

double QwtDoubleRange::value ( ) const

Returns the current value.

Reimplementado en QwtCounter.

void QwtDoubleRange::valueChange ( ) [protected, virtual]

Notify a change of value.

This virtual function is called whenever the value changes. The default implementation does nothing.

Reimplementado en QwtAbstractSlider, QwtDial, QwtSlider y QwtWheel.

La documentación para esta clase fue generada a partir de los siguientes ficheros:

src/qwt/src/qwt_double_range.h
src/qwt/src/qwt_double_range.cpp

Métodos públicos

Métodos protegidos

Descripción detallada

Documentación del constructor y destructor

Documentación de las funciones miembro