A class for drawing datetime scales. More...

#include <qwt_date_scale_draw.h>

Inheritance diagram for QwtDateScaleDraw:

Classes
class	PrivateData

Public Member Functions
	QwtDateScaleDraw (Qt::TimeSpec timeSpec=Qt::LocalTime)
	Constructor.

virtual	~QwtDateScaleDraw ()
	Destructor.

void	setDateFormat (QwtDate::IntervalType, const QString &)
	Set the default format string for an datetime interval type.

QString	dateFormat (QwtDate::IntervalType) const

void	setTimeSpec (Qt::TimeSpec)
	Set the time specification used for the tick labels.

Qt::TimeSpec	timeSpec () const

void	setUtcOffset (int seconds)
	Set the offset in seconds from Coordinated Universal Time.

int	utcOffset () const

void	setWeek0Type (QwtDate::Week0Type)
	Sets how to identify the first week of a year.

QwtDate::Week0Type	week0Type () const

virtual QwtText	label (double) const QWT_OVERRIDE
	Convert a value into its representing label.

QDateTime	toDateTime (double) const
	Translate a double value into a QDateTime object.

Public Member Functions inherited from QwtScaleDraw
	QwtScaleDraw ()
	Constructor.

virtual	~QwtScaleDraw ()
	Destructor.

void	getBorderDistHint (const QFont &, int &start, int &end) const
	Determine the minimum border distance.

int	minLabelDist (const QFont &) const
	Determine the minimum distance between two labels, that is necessary that the texts don't overlap.

int	minLength (const QFont &) const
	Calculate the minimum length that is needed to draw the scale.

virtual double	extent (const QFont &) const QWT_OVERRIDE
	Calculate the width/height that is needed for a vertical/horizontal scale.

void	move (double x, double y)
	Move the position of the scale.

void	move (const QPointF &)
	Move the position of the scale.

void	setLength (double length)
	Set the length of the backbone.

Alignment	alignment () const
	Return alignment of the scale.

void	setAlignment (Alignment)
	Set the alignment of the scale.

Qt::Orientation	orientation () const
	Return the orientation.

QPointF	pos () const

double	length () const

void	setLabelAlignment (Qt::Alignment)
	Change the label flags.

Qt::Alignment	labelAlignment () const

void	setLabelRotation (double rotation)
	Rotate all labels.

double	labelRotation () const

int	maxLabelHeight (const QFont &) const

int	maxLabelWidth (const QFont &) const

QPointF	labelPosition (double value) const
	Find the position, where to paint a label.

QRectF	labelRect (const QFont &, double value) const
	Find the bounding rectangle for the label.

QSizeF	labelSize (const QFont &, double value) const
	Calculate the size that is needed to draw a label.

QRect	boundingLabelRect (const QFont &, double value) const
	Find the bounding rectangle for the label.

Public Member Functions inherited from QwtAbstractScaleDraw
	QwtAbstractScaleDraw ()
	Constructor.

virtual	~QwtAbstractScaleDraw ()
	Destructor.

void	setScaleDiv (const QwtScaleDiv &)
	Change the scale division.

const QwtScaleDiv &	scaleDiv () const

void	setTransformation (QwtTransform *)
	Change the transformation of the scale.

const QwtScaleMap &	scaleMap () const

QwtScaleMap &	scaleMap ()

void	enableComponent (ScaleComponent, bool enable=true)
	En/Disable a component of the scale.

bool	hasComponent (ScaleComponent) const
	Check if a component is enabled.

void	setTickLength (QwtScaleDiv::TickType, double length)
	Set the length of the ticks.

double	tickLength (QwtScaleDiv::TickType) const

double	maxTickLength () const

void	setSpacing (double)
	Set the spacing between tick and labels.

double	spacing () const
	Get the spacing.

void	setPenWidthF (qreal width)
	Specify the width of the scale pen.

qreal	penWidthF () const

void	setSelected (bool on)
	设置是否选中

bool	isSelected () const
	是否选中

void	setSelectedPenWidthOffset (qreal offset=1)
	设置坐标轴在选中状态下的画笔宽度附加值

qreal	selectedPenWidthOffset () const
	获取当前坐标轴在选中状态下的画笔宽度附加值

virtual void	draw (QPainter *, const QPalette &) const
	Draw the scale.

void	setMinimumExtent (double)
	Set a minimum for the extent.

double	minimumExtent () const
	Get the minimum extent.

void	invalidateCache ()
	Invalidate the cache used by tickLabel()

Protected Member Functions
virtual QwtDate::IntervalType	intervalType (const QwtScaleDiv &) const
	Find the less detailed datetime unit, where no rounding errors happen.

virtual QString	dateFormatOfDate (const QDateTime &, QwtDate::IntervalType) const
	Format string for the representation of a datetime.

Protected Member Functions inherited from QwtScaleDraw
QTransform	labelTransformation (const QPointF &, const QSizeF &) const
	Calculate the transformation that is needed to paint a label depending on its alignment and rotation.

virtual void	drawTick (QPainter *, double value, double len) const QWT_OVERRIDE
	Draw a tick.

virtual void	drawBackbone (QPainter *) const QWT_OVERRIDE
	Draws the baseline of the scale.

virtual void	drawLabel (QPainter *, double value) const QWT_OVERRIDE
	Draws the label for a major scale tick.

Protected Member Functions inherited from QwtAbstractScaleDraw
const QwtText &	tickLabel (const QFont &, double value) const
	Convert a value into its representing label and cache it.

Additional Inherited Members
Public Types inherited from QwtScaleDraw
enum	Alignment { BottomScale , TopScale , LeftScale , RightScale }
	Alignment of the scale draw. More...

Public Types inherited from QwtAbstractScaleDraw
enum	ScaleComponent { Backbone = 0x01 , Ticks = 0x02 , Labels = 0x04 }
	Components of a scale. More...

Detailed Description

A class for drawing datetime scales.

QwtDateScaleDraw displays values as datetime labels. The format of the labels depends on the alignment of the major tick labels.

The default format strings are:

Millisecond
"hh:mm:ss:zzz\nddd dd MMM yyyy"
Second
"hh:mm:ss\nddd dd MMM yyyy"
Minute
"hh:mm\nddd dd MMM yyyy"
Hour
"hh:mm\nddd dd MMM yyyy"
Day
"ddd dd MMM yyyy"
Week
"Www yyyy"
Month
"MMM yyyy"
Year
"yyyy"

The format strings can be modified using setDateFormat() or individually for each tick label by overloading dateFormatOfDate(),

Usually QwtDateScaleDraw is used in combination with QwtDateScaleEngine, that calculates scales for datetime intervals.

See also: QwtDateScaleEngine, QwtPlot::setAxisScaleDraw()

Constructor & Destructor Documentation

◆ QwtDateScaleDraw()

QwtDateScaleDraw::QwtDateScaleDraw ( Qt::TimeSpec timeSpec = Qt::LocalTime )

explicit

Constructor.

The default setting is to display tick labels for the given time specification. The first week of a year is defined like for QwtDate::FirstThursday.

Parameters

timeSpec Time specification

See also: setTimeSpec(), setWeek0Type()

Member Function Documentation

◆ dateFormat()

QString QwtDateScaleDraw::dateFormat ( QwtDate::IntervalType intervalType ) const

Parameters

intervalType Interval type

Returns: Default format string for an datetime interval type

See also: setDateFormat(), dateFormatOfDate()

◆ dateFormatOfDate()

QString QwtDateScaleDraw::dateFormatOfDate	(	const QDateTime &	dateTime,
		QwtDate::IntervalType	intervalType
	)		const

protectedvirtual

Format string for the representation of a datetime.

dateFormatOfDate() is intended to be overloaded for situations, where formats are individual for specific datetime values.

The default setting ignores dateTime and return the default format for the interval type.

Parameters

dateTime	Datetime value
intervalType	Interval type

Returns: Format string

See also: setDateFormat(), QwtDate::toString()

◆ intervalType()

QwtDate::IntervalType QwtDateScaleDraw::intervalType ( const QwtScaleDiv & scaleDiv ) const

protectedvirtual

Find the less detailed datetime unit, where no rounding errors happen.

Parameters

scaleDiv Scale division

Returns: Interval type

See also: dateFormatOfDate()

◆ label()

QwtText QwtDateScaleDraw::label ( double value ) const

virtual

Convert a value into its representing label.

The value is converted to a datetime value using toDateTime() and converted to a plain text using QwtDate::toString().

Parameters

value Value

Returns: Label string.

See also: dateFormatOfDate()

Reimplemented from QwtAbstractScaleDraw.

◆ setDateFormat()

void QwtDateScaleDraw::setDateFormat	(	QwtDate::IntervalType	intervalType,
		const QString &	format
	)

Set the default format string for an datetime interval type.

Parameters

intervalType	Interval type
format	Default format string

See also: dateFormat(), dateFormatOfDate(), QwtDate::toString()

◆ setTimeSpec()

void QwtDateScaleDraw::setTimeSpec ( Qt::TimeSpec timeSpec )

Set the time specification used for the tick labels.

Parameters

timeSpec Time specification

See also: timeSpec(), setUtcOffset(), toDateTime()

◆ setUtcOffset()

void QwtDateScaleDraw::setUtcOffset ( int seconds )

Set the offset in seconds from Coordinated Universal Time.

Parameters

seconds Offset in seconds

Note: The offset has no effect beside for the time specification Qt::OffsetFromUTC.

See also: QDate::utcOffset(), setTimeSpec(), toDateTime()

◆ setWeek0Type()

void QwtDateScaleDraw::setWeek0Type ( QwtDate::Week0Type week0Type )

Sets how to identify the first week of a year.

Parameters

week0Type Mode how to identify the first week of a year

See also: week0Type().

Note: week0Type has no effect beside for intervals classified as QwtDate::Week.

◆ timeSpec()

Qt::TimeSpec QwtDateScaleDraw::timeSpec ( ) const

Returns: Time specification used for the tick labels

See also: setTimeSpec(), utcOffset(), toDateTime()

◆ toDateTime()

QDateTime QwtDateScaleDraw::toDateTime ( double value ) const

Translate a double value into a QDateTime object.

Returns: QDateTime object initialized with timeSpec() and utcOffset().

See also: timeSpec(), utcOffset(), QwtDate::toDateTime()

◆ utcOffset()

int QwtDateScaleDraw::utcOffset ( ) const

Returns: Offset in seconds from Coordinated Universal Time

Note: The offset has no effect beside for the time specification Qt::OffsetFromUTC.

See also: QDate::setUtcOffset(), setTimeSpec(), toDateTime()

◆ week0Type()

QwtDate::Week0Type QwtDateScaleDraw::week0Type ( ) const

Returns: Setting how to identify the first week of a year.

See also: setWeek0Type()

The documentation for this class was generated from the following files:

/home/runner/work/QWT/QWT/src/qwt_date_scale_draw.h
/home/runner/work/QWT/QWT/src/qwt_date_scale_draw.cpp

Classes

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QwtDateScaleDraw()

Member Function Documentation

◆ dateFormat()

◆ dateFormatOfDate()

◆ intervalType()

◆ label()

◆ setDateFormat()

◆ setTimeSpec()

◆ setUtcOffset()

◆ setWeek0Type()

◆ timeSpec()

◆ toDateTime()

◆ utcOffset()

◆ week0Type()