An abstract base class for drawing scales 更多...

#include <qwt_abstract_scale_draw.h>

类 QwtAbstractScaleDraw 继承关系图:

类
class	PrivateData

Public 类型
enum	ScaleComponent { Backbone = 0x01 , Ticks = 0x02 , Labels = 0x04 }
	Components of a scale 更多...

Public 成员函数
	QwtAbstractScaleDraw ()
	Constructor for QwtAbstractScaleDraw

void	setScaleDiv (const QwtScaleDiv &)
	Set the scale division

const QwtScaleDiv &	scaleDiv () const
	Return the scale division

void	setTransformation (QwtTransform *)
	Set the scale transformation

const QwtScaleMap &	scaleMap () const
	Return the scale map (const version)

QwtScaleMap &	scaleMap ()
	Return the scale map (non-const version)

void	enableComponent (ScaleComponent, bool enable=true)
	Enable or disable a scale component

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
	Get the length of the ticks

double	maxTickLength () const
	Get the length of the longest tick

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
	Get the scale pen width

void	setSelected (bool on)
	Set whether the scale draw is selected

bool	isSelected () const
	Check if the scale draw is selected

void	setSelectedPenWidthOffset (qreal offset=1)
	Set the pen width offset for the axis when it is in selected state

qreal	selectedPenWidthOffset () const
	Get the current pen width offset for the axis when it is in selected state

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

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

virtual double	extent (const QFont &font) const =0

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 成员函数
virtual void	drawTick (QPainter *painter, double value, double len) const =0

virtual void	drawBackbone (QPainter *painter) const =0

virtual void	drawLabel (QPainter *painter, double value) const =0

const QwtText &	tickLabel (const QFont &, double value) const
	Convert a value into its representing label and cache it

详细描述

An abstract base class for drawing scales

QwtAbstractScaleDraw can be used to draw linear or logarithmic scales. After a scale division has been specified as a QwtScaleDiv object using setScaleDiv(), the scale can be drawn with the draw() member.

成员枚举类型说明

◆ ScaleComponent

enum QwtAbstractScaleDraw::ScaleComponent

Components of a scale

参见: enableComponent(), hasComponent

枚举值
Backbone	Backbone = the line where the ticks are located
Ticks	Ticks
Labels	Labels

构造及析构函数说明

◆ QwtAbstractScaleDraw()

QwtAbstractScaleDraw::QwtAbstractScaleDraw ( )

Constructor for QwtAbstractScaleDraw

The range of the scale is initialized to [0, 100], the spacing (distance between ticks and labels) is set to 4, the tick lengths are set to 4, 6 and 8 pixels.

Destructor for QwtAbstractScaleDraw

成员函数说明

◆ draw()

void QwtAbstractScaleDraw::draw	(	QPainter *	painter,
		const QPalette &	palette
	)		const

virtual

Draw the scale

参数

painter	The painter
palette	Palette, text color is used for the labels, foreground color for ticks and backbone

◆ drawBackbone()

virtual void QwtAbstractScaleDraw::drawBackbone ( QPainter * painter ) const

protectedpure virtual

在 QwtRoundScaleDraw , 以及 QwtScaleDraw 内被实现.

◆ drawLabel()

virtual void QwtAbstractScaleDraw::drawLabel	(	QPainter *	painter,
		double	value
	)		const

protectedpure virtual

在 QwtRoundScaleDraw , 以及 QwtScaleDraw 内被实现.

◆ drawTick()

virtual void QwtAbstractScaleDraw::drawTick	(	QPainter *	painter,
		double	value,
		double	len
	)		const

protectedpure virtual

在 QwtRoundScaleDraw , 以及 QwtScaleDraw 内被实现.

◆ enableComponent()

void QwtAbstractScaleDraw::enableComponent	(	ScaleComponent	component,
		bool	enable = `true`
	)

Enable or disable a scale component

参数

component	Scale component (Backbone, Ticks, or Labels)
enable	True to enable, false to disable

参见: hasComponent()

◆ extent()

virtual double QwtAbstractScaleDraw::extent ( const QFont & font ) const

pure virtual

在 QwtRoundScaleDraw , 以及 QwtScaleDraw 内被实现.

◆ hasComponent()

bool QwtAbstractScaleDraw::hasComponent ( ScaleComponent component ) const

Check if a component is enabled

参数

component Component type

返回: True if component is enabled

参见: enableComponent()

◆ invalidateCache()

void QwtAbstractScaleDraw::invalidateCache ( )

Invalidate the cache used by tickLabel()

The cache is invalidated when a new QwtScaleDiv is set. If the labels need to be changed while the same QwtScaleDiv is set, invalidateCache() needs to be called manually.

◆ isSelected()

bool QwtAbstractScaleDraw::isSelected ( ) const

Check if the scale draw is selected

返回: True if selected, false otherwise

◆ label()

QwtText QwtAbstractScaleDraw::label ( double value ) const

virtual

Convert a value into its representing label

The value is converted to a plain text using QLocale().toString(value). This method is often overloaded by applications to have individual labels.

参数

value Value

返回: Label string

被 QwtCompassScaleDraw , 以及 QwtDateScaleDraw 重载.

◆ maxTickLength()

double QwtAbstractScaleDraw::maxTickLength ( ) const

Get the length of the longest tick

返回: Length of the longest tick

Useful for layout calculations

参见: tickLength(), setTickLength()

◆ minimumExtent()

double QwtAbstractScaleDraw::minimumExtent ( ) const

Get the minimum extent

返回: Minimum extent

参见: extent(), setMinimumExtent()

◆ penWidthF()

qreal QwtAbstractScaleDraw::penWidthF ( ) const

Get the scale pen width

返回: Scale pen width

参见: setPenWidth()

◆ scaleDiv()

const QwtScaleDiv & QwtAbstractScaleDraw::scaleDiv ( ) const

Return the scale division

返回: Current scale division object

◆ scaleMap() [1/2]

QwtScaleMap & QwtAbstractScaleDraw::scaleMap ( )

Return the scale map (non-const version)

返回: Map for translating between scale and pixel values

◆ scaleMap() [2/2]

const QwtScaleMap & QwtAbstractScaleDraw::scaleMap ( ) const

Return the scale map (const version)

返回: Map for translating between scale and pixel values

◆ selectedPenWidthOffset()

qreal QwtAbstractScaleDraw::selectedPenWidthOffset ( ) const

Get the current pen width offset for the axis when it is in selected state

返回: The current width offset value

参见: setSelectedPenWidthOffset()

◆ setMinimumExtent()

void QwtAbstractScaleDraw::setMinimumExtent ( double minExtent )

Set a minimum for the extent

The extent is calculated from the components of the scale draw. In situations where the labels are changing and the layout depends on the extent (e.g., scrolling a scale), setting an upper limit as minimum extent will avoid jumps of the layout.

参数

minExtent Minimum extent

参见: extent(), minimumExtent()

◆ setPenWidthF()

void QwtAbstractScaleDraw::setPenWidthF ( qreal width )

Specify the width of the scale pen

参数

width Pen width

参见: penWidth()

◆ setScaleDiv()

void QwtAbstractScaleDraw::setScaleDiv ( const QwtScaleDiv & scaleDiv )

Set the scale division

参数

scaleDiv New scale division object

This also updates the scale map and clears the label cache.

◆ setSelected()

void QwtAbstractScaleDraw::setSelected ( bool on )

Set whether the scale draw is selected

参数

on	True to select, false to deselect

◆ setSelectedPenWidthOffset()

void QwtAbstractScaleDraw::setSelectedPenWidthOffset ( qreal offset = 1 )

Set the pen width offset for the axis when it is in selected state

When an axis (e.g., X-axis or Y-axis) is selected by the user, the pen width used for drawing will be increased by this offset value, achieving a visual highlighting effect.

参数

offset The additional width value to be added when selected (unit: pixels). This value should be non-negative. If it is 0, the line width in selected state will be the same as in normal state.

参见: selectedPenWidthOffset()

◆ setSpacing()

void QwtAbstractScaleDraw::setSpacing ( double spacing )

Set the spacing between tick and labels

The spacing is the distance between ticks and labels. The default spacing is 4 pixels.

参数

spacing Spacing

参见: spacing()

◆ setTickLength()

void QwtAbstractScaleDraw::setTickLength	(	QwtScaleDiv::TickType	tickType,
		double	length
	)

Set the length of the ticks

参数

tickType	Tick type
length	New length

警告: The length is limited to [0..1000]

◆ setTransformation()

void QwtAbstractScaleDraw::setTransformation ( QwtTransform * transformation )

Set the scale transformation

参数

transformation New scale transformation object

◆ spacing()

double QwtAbstractScaleDraw::spacing ( ) const

Get the spacing

The spacing is the distance between ticks and labels. The default spacing is 4 pixels.

返回: Spacing

参见: setSpacing()

◆ tickLabel()

const QwtText & QwtAbstractScaleDraw::tickLabel	(	const QFont &	font,
		double	value
	)		const

protected

Convert a value into its representing label and cache it

The conversion between value and label is called very often in the layout and painting code. Unfortunately the calculation of the label sizes might be slow (really slow for rich text in Qt4), so it's necessary to cache the labels.

参数

font	Font
value	Value

返回: Tick label

◆ tickLength()

double QwtAbstractScaleDraw::tickLength ( QwtScaleDiv::TickType tickType ) const

Get the length of the ticks

返回: Length of the ticks

参见: setTickLength(), maxTickLength()

该类的文档由以下文件生成:

/home/runner/work/QWT/QWT/src/plot/qwt_abstract_scale_draw.h
/home/runner/work/QWT/QWT/src/plot/qwt_abstract_scale_draw.cpp

类

Public 类型

Public 成员函数

Protected 成员函数

详细描述

成员枚举类型说明

◆ ScaleComponent

构造及析构函数说明

◆ QwtAbstractScaleDraw()

成员函数说明

◆ draw()

◆ drawBackbone()

◆ drawLabel()

◆ drawTick()

◆ enableComponent()

◆ extent()

◆ hasComponent()

◆ invalidateCache()

◆ isSelected()

◆ label()

◆ maxTickLength()

◆ minimumExtent()

◆ penWidthF()

◆ scaleDiv()

◆ scaleMap() [1/2]

◆ scaleMap() [2/2]

◆ selectedPenWidthOffset()

◆ setMinimumExtent()

◆ setPenWidthF()

◆ setScaleDiv()

◆ setSelected()

◆ setSelectedPenWidthOffset()

◆ setSpacing()

◆ setTickLength()

◆ setTransformation()

◆ spacing()

◆ tickLabel()

◆ tickLength()