QwtPlotTradingCurve illustrates movements in the price of a financial instrument over time. More...

#include <qwt_plot_tradingcurve.h>

Inheritance diagram for QwtPlotTradingCurve:

Classes
class	PrivateData
Public Types
enum	Direction { Increasing, Decreasing }
	Direction of a price movement. More...
enum	PaintAttribute { ClipSymbols = 0x01 }
typedef QFlags< PaintAttribute >	PaintAttributes
	Paint attributes.
enum	SymbolStyle { NoSymbol = -1, Bar, CandleStick, UserSymbol = 100 }
	Symbol styles. More...
Public Member Functions
virtual QRectF	boundingRect () const
virtual void	drawSeries (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const
virtual QwtGraphic	legendIcon (int index, const QSizeF &) const
double	maxSymbolWidth () const
double	minSymbolWidth () const
	QwtPlotTradingCurve (const QString &title=QString::null)
	QwtPlotTradingCurve (const QwtText &title)
virtual int	rtti () const
void	setMaxSymbolWidth (double)
void	setMinSymbolWidth (double)
void	setPaintAttribute (PaintAttribute, bool on=true)
void	setSamples (const QVector< QwtOHLCSample > &)
void	setSamples (QwtSeriesData< QwtOHLCSample > *)
void	setSymbolBrush (Direction, const QBrush &)
void	setSymbolExtent (double width)
	Set the extent of the symbol.
void	setSymbolPen (const QColor &, qreal width=0.0, Qt::PenStyle=Qt::SolidLine)
void	setSymbolPen (const QPen &)
	Set the symbol pen.
void	setSymbolStyle (SymbolStyle style)
QBrush	symbolBrush (Direction) const
double	symbolExtent () const
QPen	symbolPen () const
SymbolStyle	symbolStyle () const
bool	testPaintAttribute (PaintAttribute) const
virtual	~QwtPlotTradingCurve ()
	Destructor.
Protected Member Functions
void	drawBar (QPainter *painter, const QwtOHLCSample &, Qt::Orientation, bool inverted, double width) const
	Draw a bar.
void	drawCandleStick (QPainter *, const QwtOHLCSample &, Qt::Orientation, double width) const
	Draw a candle stick.
virtual void	drawSymbols (QPainter *, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect, int from, int to) const
virtual void	drawUserSymbol (QPainter *, SymbolStyle, const QwtOHLCSample &, Qt::Orientation, bool inverted, double width) const
	Draw a symbol for a symbol style >= UserSymbol.
void	init ()
	Initialize internal members.
virtual double	scaledSymbolWidth (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRectF &canvasRect) const
Private Attributes
PrivateData *	d_data

Detailed Description

QwtPlotTradingCurve illustrates movements in the price of a financial instrument over time.

QwtPlotTradingCurve supports candlestick or bar ( OHLC ) charts that are used in the domain of technical analysis.

While the length ( height or width depending on orientation() ) of each symbol depends on the corresponding OHLC sample the size of the other dimension can be controlled using:

setSymbolExtent()
setSymbolMinWidth()
setSymbolMaxWidth()

The extent is a size in scale coordinates, so that the symbol width is increasing when the plot is zoomed in. Minimum/Maximum width is in widget coordinates independent from the zoom level. When setting the minimum and maximum to the same value, the width of the symbol is fixed.

Definition at line 38 of file qwt_plot_tradingcurve.h.

Member Typedef Documentation

typedef QFlags<PaintAttribute> QwtPlotTradingCurve::PaintAttributes

Paint attributes.

Definition at line 102 of file qwt_plot_tradingcurve.h.

Member Enumeration Documentation

enum QwtPlotTradingCurve::Direction

Direction of a price movement.

Enumerator:

Increasing	The closing price is higher than the opening price.
Decreasing	The closing price is lower than the opening price.

Definition at line 82 of file qwt_plot_tradingcurve.h.

enum QwtPlotTradingCurve::PaintAttribute

Attributes to modify the drawing algorithm.

See also:: setPaintAttribute(), testPaintAttribute()

Enumerator:

ClipSymbols

Check if a symbol is on the plot canvas before painting it.

Definition at line 95 of file qwt_plot_tradingcurve.h.

enum QwtPlotTradingCurve::SymbolStyle

Symbol styles.

The default setting is QwtPlotSeriesItem::CandleStick.

See also:: setSymbolStyle(), symbolStyle()

Enumerator:

NoSymbol	Nothing is displayed.
Bar	A line on the chart shows the price range (the highest and lowest prices) over one unit of time, e.g. one day or one hour. Tick marks project from each side of the line indicating the opening and closing price.
CandleStick	The range between opening/closing price are displayed as a filled box. The fill brush depends on the direction of the price movement. The box is connected to the highest/lowest values by lines.
UserSymbol	SymbolTypes >= UserSymbol are displayed by drawUserSymbol(), that needs to be overloaded and implemented in derived curve classes. See also: drawUserSymbol()

Definition at line 48 of file qwt_plot_tradingcurve.h.

Constructor & Destructor Documentation

QwtPlotTradingCurve::QwtPlotTradingCurve ( const QString & title = QString::null ) [explicit]

Constructor

Parameters:

title Title of the curve

Definition at line 67 of file qwt_plot_tradingcurve.cpp.

QwtPlotTradingCurve::QwtPlotTradingCurve ( const QwtText & title ) [explicit]

Constructor

Parameters:

title Title of the curve

Definition at line 57 of file qwt_plot_tradingcurve.cpp.

QwtPlotTradingCurve::~QwtPlotTradingCurve ( ) [virtual]

Destructor.

Definition at line 74 of file qwt_plot_tradingcurve.cpp.

Member Function Documentation

QRectF QwtPlotTradingCurve::boundingRect ( ) const [virtual]

Returns:: Bounding rectangle of all samples. For an empty series the rectangle is invalid.

Reimplemented from QwtPlotSeriesItem.

Definition at line 359 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::drawBar	(	QPainter *	painter,
		const QwtOHLCSample &	sample,
		Qt::Orientation	orientation,
		bool	inverted,
		double	width
	)		const `[protected]`

Draw a bar.

Parameters:

painter	Qt painter, initialized with pen/brush
sample	Sample, already translated into paint device coordinates
orientation	Vertical or horizontal
inverted	When inverted is false the open tick is painted to the left/top, otherwise it is painted right/bottom. The close tick is painted in the opposite direction of the open tick. painted in the opposite d opposite direction.
width	Width or height of the candle, depending on the orientation

See also:: Bar

Definition at line 556 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::drawCandleStick	(	QPainter *	painter,
		const QwtOHLCSample &	sample,
		Qt::Orientation	orientation,
		double	width
	)		const `[protected]`

Draw a candle stick.

Parameters:

painter	Qt painter, initialized with pen/brush
sample	Samples already translated into paint device coordinates
orientation	Vertical or horizontal
width	Width or height of the candle, depending on the orientation

See also:: CandleStick

Definition at line 595 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::drawSeries	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to
	)		const `[virtual]`

Draw an interval of the curve

Parameters:

painter	Painter
xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rectangle of the canvas
from	Index of the first point to be painted
to	Index of the last point to be painted. If to < 0 the curve will be painted to its last point.

See also:: drawSymbols()

Implements QwtPlotSeriesItem.

Definition at line 381 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::drawSymbols	(	QPainter *	painter,
		const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect,
		int	from,
		int	to
	)		const `[protected, virtual]`

Draw symbols

Parameters:

painter	Painter
xMap	x map
yMap	y map
canvasRect	Contents rectangle of the canvas
from	Index of the first point to be painted
to	Index of the last point to be painted

See also:: drawSeries()

Definition at line 414 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::drawUserSymbol	(	QPainter *	painter,
		SymbolStyle	symbolStyle,
		const QwtOHLCSample &	sample,
		Qt::Orientation	orientation,
		bool	inverted,
		double	symbolWidth
	)		const `[protected, virtual]`

Draw a symbol for a symbol style >= UserSymbol.

The implementation does nothing and is intended to be overloaded

Parameters:

painter	Qt painter, initialized with pen/brush
symbolStyle	Symbol style
sample	Samples already translated into paint device coordinates
orientation	Vertical or horizontal
inverted	True, when the opposite scale ( Qt::Vertical: x, Qt::Horizontal: y ) is increasing in the opposite direction as QPainter coordinates.
symbolWidth	Width of the symbol in paint device coordinates

Definition at line 528 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::init ( ) [protected]

Initialize internal members.

Definition at line 80 of file qwt_plot_tradingcurve.cpp.

QwtGraphic QwtPlotTradingCurve::legendIcon	(	int	index,
		const QSizeF &	size
	)		const `[virtual]`

Returns:: A rectangle filled with the color of the symbol pen

Parameters:

index	Index of the legend entry ( usually there is only one )
size	Icon size

See also:: setLegendIconSize(), legendData()

Reimplemented from QwtPlotItem.

Definition at line 636 of file qwt_plot_tradingcurve.cpp.

double QwtPlotTradingCurve::maxSymbolWidth ( ) const

Returns:: Maximum for the symbol width

See also:: setMaxSymbolWidth(), minSymbolWidth(), symbolExtent()

Definition at line 350 of file qwt_plot_tradingcurve.cpp.

double QwtPlotTradingCurve::minSymbolWidth ( ) const

Returns:: Minmum for the symbol width

See also:: setMinSymbolWidth(), maxSymbolWidth(), symbolExtent()

Definition at line 322 of file qwt_plot_tradingcurve.cpp.

int QwtPlotTradingCurve::rtti ( ) const [virtual]

Returns:: QwtPlotItem::Rtti_PlotTradingCurve

Reimplemented from QwtPlotItem.

Definition at line 92 of file qwt_plot_tradingcurve.cpp.

double QwtPlotTradingCurve::scaledSymbolWidth	(	const QwtScaleMap &	xMap,
		const QwtScaleMap &	yMap,
		const QRectF &	canvasRect
	)		const `[protected, virtual]`

Calculate the symbol width in paint coordinates

The width is calculated by scaling the symbol extent into paint device coordinates bounded by the minimum/maximum symbol width.

Parameters:

xMap	Maps x-values into pixel coordinates.
yMap	Maps y-values into pixel coordinates.
canvasRect	Contents rectangle of the canvas

Returns:: Symbol width in paint coordinates

See also:: symbolExtent(), minSymbolWidth(), maxSymbolWidth()

Definition at line 658 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setMaxSymbolWidth ( double width )

Set a maximum for the symbol width

A value <= 0.0 means an unlimited width

Parameters:

width Width in paint device coordinates

See also:: maxSymbolWidth(), setMinSymbolWidth(), setSymbolExtent()

Definition at line 335 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setMinSymbolWidth ( double width )

Set a minimum for the symbol width

Parameters:

width Width in paint device coordinates

See also:: minSymbolWidth(), setMaxSymbolWidth(), setSymbolExtent()

Definition at line 306 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setPaintAttribute	(	PaintAttribute	attribute,
		bool	on = `true`
	)

Specify an attribute how to draw the curve

Parameters:

attribute	Paint attribute
on	On/Off

See also:: testPaintAttribute()

Definition at line 104 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setSamples ( const QVector< QwtOHLCSample > & samples )

Initialize data with an array of samples.

Parameters:

samples Vector of samples

See also:: QwtPlotSeriesItem::setData()

Definition at line 129 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setSamples ( QwtSeriesData< QwtOHLCSample > * data )

Assign a series of samples

setSamples() is just a wrapper for setData() without any additional value - beside that it is easier to find for the developer.

Parameters:

data Data

Warning:: The item takes ownership of the data object, deleting it when its not used anymore.

Definition at line 145 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setSymbolBrush	(	Direction	direction,
		const QBrush &	brush
	)

Set the symbol brush

Parameters:

direction	Direction type
brush	Brush used to fill the body of all candlestick symbols with the direction

See also:: symbolBrush(), setSymbolPen()

Definition at line 235 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setSymbolExtent ( double extent )

Set the extent of the symbol.

The width of the symbol is given in scale coordinates. When painting a symbol the width is scaled into paint device coordinates by scaledSymbolWidth(). The scaled width is bounded by minSymbolWidth(), maxSymbolWidth()

Parameters:

extent Symbol width in scale coordinates

See also:: symbolExtent(), scaledSymbolWidth(), setMinSymbolWidth(), setMaxSymbolWidth()

Definition at line 278 of file qwt_plot_tradingcurve.cpp.

void QwtPlotTradingCurve::setSymbolPen	(	const QColor &	color,
		qreal	width = `0.0`,
		Qt::PenStyle	style = `Qt::SolidLine`
	)

Build and assign the symbol pen

In Qt5 the default pen width is 1.0 ( 0.0 in Qt4 ) what makes it non cosmetic ( see QPen::isCosmetic() ). This method has been introduced to hide this incompatibility.

Parameters: