QwtDialNeedle - Man Page

Base class for needles that can be used in a QwtDial.

Synopsis

#include <qwt_dial_needle.h>

Inherited by QwtCompassMagnetNeedle, QwtCompassWindArrow, and QwtDialSimpleNeedle.

QwtDialNeedle ()
Constructor.
virtual ~QwtDialNeedle ()
Destructor.
virtual void setPalette (const QPalette &)
const QPalette & palette () const
virtual void draw (QPainter *painter, const QPointF &center, double length, double direction, QPalette::ColorGroup=QPalette::Active) const

Protected Member Functions

virtual void drawNeedle (QPainter *painter, double length, QPalette::ColorGroup colorGroup) const =0
Draw the needle.
virtual void drawKnob (QPainter *, double width, const QBrush &, bool sunken) const
Draw the knob.

Detailed Description

Base class for needles that can be used in a QwtDial.

QwtDialNeedle is a pointer that indicates a value by pointing to a specific direction.

See also: QwtDial, QwtCompass

Member Function Documentation

void QwtDialNeedle::draw (QPainter * painter, const QPointF & center, double length, double direction, QPalette::ColorGroup colorGroup = QPalette::Active) const [virtual]

Draw the needle

Parameters: painter Painter
center Center of the dial, start position for the needle
length Length of the needle
direction Direction of the needle, in degrees counter clockwise
colorGroup Color group, used for painting

virtual void QwtDialNeedle::drawNeedle (QPainter * painter, double length, QPalette::ColorGroup colorGroup) const [protected], [pure virtual]

Draw the needle. The origin of the needle is at position (0.0, 0.0 ) pointing in direction 0.0 ( = east ).

The painter is already initialized with translation and rotation.

Parameters: painter Painter
length Length of the needle
colorGroup Color group, used for painting
See also: setPalette(), palette()

Implemented in QwtCompassWindArrow, QwtCompassMagnetNeedle, and QwtDialSimpleNeedle.