QwtKnob Class Reference

#include <qwt_knob.h>

Inheritance diagram for QwtKnob:

List of all members.

Public Types
enum	Symbol {   Line,   Dot }
Public Types inherited from QwtAbstractSlider
enum	ScrollMode {   ScrNone,   ScrMouse,   ScrTimer,   ScrDirect,   ScrPage }

Public Member Functions
	QwtKnob (QWidget *parent=NULL)
virtual	~QwtKnob ()
int	borderWidth () const
int	knobWidth () const
virtual QSize	minimumSizeHint () const
const QwtRoundScaleDraw *	scaleDraw () const
QwtRoundScaleDraw *	scaleDraw ()
void	setBorderWidth (int bw)
void	setKnobWidth (int w)
void	setScaleDraw (QwtRoundScaleDraw *)
void	setSymbol (Symbol)
void	setTotalAngle (double angle)
virtual QSize	sizeHint () const
Symbol	symbol () const
double	totalAngle () const
Public Member Functions inherited from QwtAbstractSlider
	QwtAbstractSlider (Qt::Orientation, QWidget *parent=NULL)
virtual	~QwtAbstractSlider ()
bool	isReadOnly () const
bool	isValid () const
virtual double	mass () const
Qt::Orientation	orientation () const
virtual void	setMass (double val)
virtual void	setOrientation (Qt::Orientation o)
void	setTracking (bool enable)
void	setUpdateTime (int t)
void	setValid (bool valid)
void	stopMoving ()
Public Member Functions inherited from QwtDoubleRange
	QwtDoubleRange ()
virtual	~QwtDoubleRange ()
virtual void	incPages (int)
double	maxValue () const
double	minValue () const
int	pageSize () const
bool	periodic () const
void	setPeriodic (bool tf)
void	setRange (double vmin, double vmax, double vstep=0.0, int pagesize=1)
void	setStep (double)
double	step () const
double	value () const
Public Member Functions inherited from QwtAbstractScale
	QwtAbstractScale ()
virtual	~QwtAbstractScale ()
bool	autoScale () const
const QwtScaleEngine *	scaleEngine () const
QwtScaleEngine *	scaleEngine ()
const QwtScaleMap &	scaleMap () const
int	scaleMaxMajor () const
int	scaleMaxMinor () const
void	setAutoScale ()
void	setScale (double vmin, double vmax, double step=0.0)
void	setScale (const QwtDoubleInterval &, double step=0.0)
void	setScale (const QwtScaleDiv &s)
void	setScaleEngine (QwtScaleEngine *)
void	setScaleMaxMajor (int ticks)
void	setScaleMaxMinor (int ticks)

Protected Member Functions
void	draw (QPainter *p, const QRect &ur)
void	drawKnob (QPainter *p, const QRect &r)
void	drawMarker (QPainter *p, double arc, const QColor &c)
virtual void	paintEvent (QPaintEvent *e)
virtual void	resizeEvent (QResizeEvent *e)
Protected Member Functions inherited from QwtAbstractSlider
virtual void	keyPressEvent (QKeyEvent *e)
virtual void	mouseMoveEvent (QMouseEvent *e)
double	mouseOffset () const
virtual void	mousePressEvent (QMouseEvent *e)
virtual void	mouseReleaseEvent (QMouseEvent *e)
int	scrollMode () const
void	setMouseOffset (double)
virtual void	setPosition (const QPoint &)
virtual void	timerEvent (QTimerEvent *e)
virtual void	wheelEvent (QWheelEvent *e)
Protected Member Functions inherited from QwtDoubleRange
double	exactPrevValue () const
double	exactValue () const
double	prevValue () const
virtual void	stepChange ()
Protected Member Functions inherited from QwtAbstractScale
const QwtAbstractScaleDraw *	abstractScaleDraw () const
QwtAbstractScaleDraw *	abstractScaleDraw ()
void	rescale (double vmin, double vmax, double step=0.0)
void	setAbstractScaleDraw (QwtAbstractScaleDraw *)

Additional Inherited Members
Public Slots inherited from QwtAbstractSlider
virtual void	fitValue (double val)
virtual void	incValue (int steps)
virtual void	setReadOnly (bool)
virtual void	setValue (double val)
Signals inherited from QwtAbstractSlider
void	sliderMoved (double value)
void	sliderPressed ()
void	sliderReleased ()
void	valueChanged (double value)

---

Detailed Description

The Knob Widget.

The QwtKnob widget imitates look and behaviour of a volume knob on a radio. It contains a scale around the knob which is set up automatically or can be configured manually (see QwtAbstractScale). Automatic scrolling is enabled when the user presses a mouse button on the scale. For a description of signals, slots and other members, see QwtAbstractSlider.

See also:

QwtAbstractSlider and QwtAbstractScale for the descriptions of the inherited members.

---

Member Enumeration Documentation

enum QwtKnob::Symbol

Symbol

See also:

QwtKnob::QwtKnob()

---

Constructor & Destructor Documentation

QwtKnob::QwtKnob ( QWidget *  parent = NULL )

explicit

Constructor

Parameters:

parent

Parent widget

---

Member Function Documentation

void QwtKnob::draw ( QPainter *  painter, const QRect &  rect  )

protected

Repaint the knob

Parameters:

painter	Painter
rect	Update rectangle

void QwtKnob::drawKnob ( QPainter *  painter, const QRect &  r  )

protected

Draw the knob.

Parameters:

painter	painter
r	Bounding rectangle of the knob (without scale)

void QwtKnob::drawMarker ( QPainter *  p, double  arc, const QColor &  c  )

protected

Draw the marker at the knob's front.

Parameters:

p	Painter
arc	Angle of the marker
c	Marker color

QSize QwtKnob::minimumSizeHint ( ) const

virtual

Return a minimum size hint.

Warning:

The return value of QwtKnob::minimumSizeHint() depends on the font and the scale.

void QwtKnob::paintEvent ( QPaintEvent *  e )

protectedvirtual

Repaint the knob

Parameters:

e	Paint event

void QwtKnob::resizeEvent ( QResizeEvent *  e )

protectedvirtual

Qt Resize Event

const QwtRoundScaleDraw * QwtKnob::scaleDraw

(

)

const

Returns:

the scale draw of the knob

See also:

setScaleDraw()

QwtRoundScaleDraw * QwtKnob::scaleDraw

(

)

Returns:

the scale draw of the knob

See also:

setScaleDraw()

void QwtKnob::setBorderWidth

(

int

bw

)

Set the knob's border width.

Parameters:

bw	new border width

void QwtKnob::setKnobWidth

(

int

w

)

Change the knob's width.

The specified width must be >= 5, or it will be clipped.

Parameters:

w

New width

void QwtKnob::setScaleDraw

(

QwtRoundScaleDraw *

scaleDraw

)

Change the scale draw of the knob

For changing the labels of the scales, it is necessary to derive from QwtRoundScaleDraw and overload QwtRoundScaleDraw::label().

See also:

scaleDraw()

void QwtKnob::setSymbol

(

QwtKnob::Symbol

s

)

Set the symbol of the knob.

See also:

symbol()

void QwtKnob::setTotalAngle

(

double

angle

)

Set the total angle by which the knob can be turned.

Parameters:

angle

Angle in degrees.

The default angle is 270 degrees. It is possible to specify an angle of more than 360 degrees so that the knob can be turned several times around its axis.

QSize QwtKnob::sizeHint ( ) const

virtual

Returns:

minimumSizeHint()

QwtKnob::Symbol QwtKnob::symbol

(

)

const

Returns:

symbol of the knob

See also:

setSymbol()