#include <qwt_knob.h>

Inherits QwtAbstractSlider, and QwtAbstractScale.

Public Types
enum	KnobStyle { NoStyle = -1, Raised, Sunken }
enum	MarkerStyle { NoMarker = -1, Tick, Dot, Nub, Notch }
enum	ScrollMode { ScrNone, ScrMouse, ScrTimer, ScrDirect, ScrPage }
Public Slots
virtual void	fitValue (double val)
virtual void	incValue (int steps)
virtual void	setReadOnly (bool)
virtual void	setValue (double val)
Signals
void	sliderMoved (double value)
void	sliderPressed ()
void	sliderReleased ()
void	valueChanged (double value)
Public Member Functions
bool	autoScale () const
int	borderWidth () const
virtual void	incPages (int)
bool	isReadOnly () const
bool	isValid () const
KnobStyle	knobStyle () const
int	knobWidth () const
int	markerSize () const
MarkerStyle	markerStyle () const
virtual double	mass () const
double	maxValue () const
virtual QSize	minimumSizeHint () const
double	minValue () const
Qt::Orientation	orientation () const
int	pageSize () const
bool	periodic () const
	QwtKnob (QWidget *parent=NULL)
const QwtRoundScaleDraw *	scaleDraw () const
QwtRoundScaleDraw *	scaleDraw ()
const QwtScaleEngine *	scaleEngine () const
QwtScaleEngine *	scaleEngine ()
const QwtScaleMap &	scaleMap () const
int	scaleMaxMajor () const
int	scaleMaxMinor () const
void	setAutoScale ()
void	setBorderWidth (int bw)
void	setKnobStyle (KnobStyle)
void	setKnobWidth (int w)
void	setMarkerSize (int)
void	setMarkerStyle (MarkerStyle)
virtual void	setMass (double val)
virtual void	setOrientation (Qt::Orientation o)
void	setPeriodic (bool tf)
void	setRange (double vmin, double vmax, double vstep=0.0, int pagesize=1)
void	setScale (double vmin, double vmax, double step=0.0)
void	setScale (const QwtInterval &, double step=0.0)
void	setScale (const QwtScaleDiv &)
void	setScaleDraw (QwtRoundScaleDraw *)
void	setScaleEngine (QwtScaleEngine *)
void	setScaleMaxMajor (int ticks)
void	setScaleMaxMinor (int ticks)
void	setStep (double)
void	setTotalAngle (double angle)
void	setTracking (bool enable)
void	setUpdateTime (int t)
void	setValid (bool valid)
virtual QSize	sizeHint () const
double	step () const
void	stopMoving ()
double	totalAngle () const
double	value () const
virtual	~QwtKnob ()
Protected Member Functions
const QwtAbstractScaleDraw *	abstractScaleDraw () const
QwtAbstractScaleDraw *	abstractScaleDraw ()
virtual void	changeEvent (QEvent *)
virtual void	drawKnob (QPainter *, const QRectF &) const
virtual void	drawMarker (QPainter *, const QRectF &, double arc) const
double	exactPrevValue () const
double	exactValue () const
virtual void	getScrollMode (const QPoint &, QwtAbstractSlider::ScrollMode &, int &direction) const
virtual double	getValue (const QPoint &p)
virtual void	keyPressEvent (QKeyEvent *e)
virtual void	mouseMoveEvent (QMouseEvent *e)
double	mouseOffset () const
virtual void	mousePressEvent (QMouseEvent *e)
virtual void	mouseReleaseEvent (QMouseEvent *e)
virtual void	paintEvent (QPaintEvent *)
double	prevValue () const
void	rescale (double vmin, double vmax, double step=0.0)
virtual void	resizeEvent (QResizeEvent *)
int	scrollMode () const
void	setAbstractScaleDraw (QwtAbstractScaleDraw *)
void	setMouseOffset (double)
virtual void	setPosition (const QPoint &)
virtual void	stepChange ()
virtual void	timerEvent (QTimerEvent *e)
virtual void	wheelEvent (QWheelEvent *e)

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::KnobStyle

Style of the knob surface.

Depending on the KnobStyle the surface of the knob is filled from the brushes of the widget palette().

See also:: setKnobStyle(), knobStyle()

Enumerator:

NoStyle	Fill the knob with a brush from QPalette::Button.
Raised	Build a gradient from QPalette::Midlight and QPalette::Button.
Sunken	Build a gradient from QPalette::Midlight, QPalette::Button and QPalette::Midlight

enum QwtKnob::MarkerStyle

Marker type.

The marker indicates the current value on the knob The default setting is a Notch marker.

See also:: setMarkerStyle(), setMarkerSize()

Enumerator:

NoMarker	Don't paint any marker.
Tick	Paint a single tick in QPalette::ButtonText color.
Dot	Paint a circle in QPalette::ButtonText color.
Nub	Draw a raised ellipse with a gradient build from QPalette::Light and QPalette::Mid
Notch	Draw a sunken ellipse with a gradient build from QPalette::Light and QPalette::Mid

enum QwtAbstractSlider::ScrollMode [inherited]

Scroll mode

See also:: getScrollMode()

Enumerator:

ScrNone	Scrolling switched off. Don't change the value.
ScrMouse	Change the value while the user keeps the button pressed and moves the mouse.
ScrTimer	Automatic scrolling. Increment the value in the specified direction as long as the user keeps the button pressed.
ScrPage	Automatic scrolling. Same as ScrTimer, but increment by page size.

Constructor & Destructor Documentation

QwtKnob::QwtKnob ( QWidget * parent = NULL ) [explicit]

Constructor

Parameters:

parent Parent widget

QwtKnob::~QwtKnob ( ) [virtual]

Destructor.

Member Function Documentation

const QwtAbstractScaleDraw * QwtAbstractScale::abstractScaleDraw ( ) const [protected, inherited]

Returns:: Scale draw

See also:: setAbstractScaleDraw()

QwtAbstractScaleDraw * QwtAbstractScale::abstractScaleDraw ( ) [protected, inherited]

Returns:: Scale draw

See also:: setAbstractScaleDraw()

bool QwtAbstractScale::autoScale ( ) const [inherited]

Returns:: true if autoscaling is enabled

int QwtKnob::borderWidth ( ) const

Return the border width.

void QwtKnob::changeEvent ( QEvent * event ) [protected, virtual]

Handle QEvent::StyleChange and QEvent::FontChange;

Parameters:

event Change event

void QwtKnob::drawKnob	(	QPainter *	painter,
		const QRectF &	knobRect
	)		const `[protected, virtual]`

Draw the knob.

Parameters:

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

void QwtKnob::drawMarker	(	QPainter *	painter,
		const QRectF &	rect,
		double	angle
	)		const `[protected, virtual]`

Draw the marker at the knob's front.

Parameters:

painter	Painter
rect	Bounding rectangle of the knob without scale
angle	Angle of the marker in degrees

double QwtDoubleRange::exactPrevValue ( ) const [protected, inherited]

Returns the exact previous value.

double QwtDoubleRange::exactValue ( ) const [protected, inherited]

Returns the exact value.

The exact value is the value which QwtDoubleRange::value would return if the value were not adjusted to the step raster. It differs from the current value only if fitValue() or incValue() have been used before. This function is intended for internal use in derived classes.

void QwtAbstractSlider::fitValue ( double value ) [virtual, slot, inherited]

Set the slider's value to the nearest integer multiple of the step size.

Parameters:

value Value

See also:: setValue(), incValue()

Reimplemented from QwtDoubleRange.

void QwtKnob::getScrollMode	(	const QPoint &	pos,
		QwtAbstractSlider::ScrollMode &	scrollMode,
		int &	direction
	)		const `[protected, virtual]`

Set the scrolling mode and direction.

Called by QwtAbstractSlider

Parameters:

pos	Point in question
scrollMode	Scrolling mode
direction	Direction

Implements QwtAbstractSlider.

double QwtKnob::getValue ( const QPoint & pos ) [protected, virtual]

Determine the value corresponding to a specified position.

Called by QwtAbstractSlider

Parameters:

pos point

Implements QwtAbstractSlider.

void QwtDoubleRange::incPages ( int nPages ) [virtual, inherited]

Increment the value by a specified number of pages.

Parameters:

nPages Number of pages to increment. A negative number decrements the value.

Warning:: The Page size is specified in the constructor.

void QwtAbstractSlider::incValue ( int steps ) [virtual, slot, inherited]

Increment the value by a specified number of steps.

Parameters:

steps number of steps

See also:: setValue()

Reimplemented from QwtDoubleRange.

bool QwtAbstractSlider::isReadOnly ( ) const [inherited]

In read only mode the slider can't be controlled by mouse or keyboard.

Returns:: true if read only

See also:: setReadOnly()

bool QwtAbstractSlider::isValid ( ) const [inline, inherited]

See also:: QwtDblRange::isValid()

Reimplemented from QwtDoubleRange.

void QwtAbstractSlider::keyPressEvent ( QKeyEvent * e ) [protected, virtual, inherited]

Handles key events

Key_Down, KeyLeft
Decrement by 1
Key_Up, Key_Right
Increment by 1

Parameters:

e Key event

See also:: isReadOnly()

Reimplemented in QwtDial, and QwtCompass.

QwtKnob::KnobStyle QwtKnob::knobStyle ( ) const

Returns:: Marker type of the knob

See also:: setKnobStyle(), setBorderWidth()

int QwtKnob::knobWidth ( ) const

Return the width of the knob.

int QwtKnob::markerSize ( ) const

Return the marker size.

QwtKnob::MarkerStyle QwtKnob::markerStyle ( ) const

Returns:: Marker type of the knob

See also:: setMarkerStyle(), setMarkerSize()

double QwtAbstractSlider::mass ( ) const [virtual, inherited]

Returns:: mass

See also:: setMass()

Reimplemented in QwtWheel.

double QwtDoubleRange::maxValue ( ) const [inherited]

Returns the value of the second border of the range.

maxValue returns the value which has been specified as the second parameter in QwtDoubleRange::setRange.

See also:: setRange()

Reimplemented in QwtCounter.

QSize QwtKnob::minimumSizeHint ( ) const [virtual]

Return a minimum size hint.

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

double QwtDoubleRange::minValue ( ) const [inherited]

Returns the value at the first border of the range.

minValue returns the value which has been specified as the first parameter in setRange().

See also:: setRange()

Reimplemented in QwtCounter.

void QwtAbstractSlider::mouseMoveEvent ( QMouseEvent * e ) [protected, virtual, inherited]

Mouse Move Event handler

Parameters:

e	Mouse event

double QwtAbstractSlider::mouseOffset ( ) const [protected, inherited]

See also:: setMouseOffset()

void QwtAbstractSlider::mousePressEvent ( QMouseEvent * e ) [protected, virtual, inherited]

Mouse press event handler

Parameters:

e	Mouse event

void QwtAbstractSlider::mouseReleaseEvent ( QMouseEvent * e ) [protected, virtual, inherited]

Mouse Release Event handler

Parameters:

e	Mouse event

Qt::Orientation QwtAbstractSlider::orientation ( ) const [inherited]

Returns:: Orientation

See also:: setOrientation()

int QwtDoubleRange::pageSize ( ) const [inherited]

Returns the page size in steps.

void QwtKnob::paintEvent ( QPaintEvent * event ) [protected, virtual]

Repaint the knob

Parameters:

event Paint event

bool QwtDoubleRange::periodic ( ) const [inherited]

Returns true if the range is periodic.

See also:: setPeriodic()

double QwtDoubleRange::prevValue ( ) const [protected, inherited]

Returns the previous value.

void QwtAbstractScale::rescale	(	double	vmin,
		double	vmax,
		double	stepSize = `0.0`
	)		`[protected, inherited]`

Recalculate the scale division and update the scale draw.

Parameters:

vmin	Lower limit of the scale interval
vmax	Upper limit of the scale interval
stepSize	Major step size

See also:: scaleChange()

void QwtKnob::resizeEvent ( QResizeEvent * event ) [protected, virtual]

Qt Resize Event

Parameters:

event 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()

const QwtScaleEngine * QwtAbstractScale::scaleEngine ( ) const [inherited]

Returns:: Scale engine

See also:: setScaleEngine()

QwtScaleEngine * QwtAbstractScale::scaleEngine ( ) [inherited]

Returns:: Scale engine

See also:: setScaleEngine()

const QwtScaleMap & QwtAbstractScale::scaleMap ( ) const [inherited]

Returns:: abstractScaleDraw()->scaleMap()

int QwtAbstractScale::scaleMaxMajor ( ) const [inherited]

Returns:: Max. number of major tick intervals The default value is 5.

int QwtAbstractScale::scaleMaxMinor ( ) const [inherited]

Returns:: Max. number of minor tick intervals The default value is 3.

int QwtAbstractSlider::scrollMode ( ) const [protected, inherited]

sa ScrollMode

void QwtAbstractScale::setAbstractScaleDraw ( QwtAbstractScaleDraw * scaleDraw ) [protected, inherited]

Set a scale draw.

scaleDraw has to be created with new and will be deleted in ~QwtAbstractScale or the next call of setAbstractScaleDraw.

void QwtAbstractScale::setAutoScale ( ) [inherited]

Advise the widget to control the scale range internally.

Autoscaling is on by default.

See also:: setScale(), autoScale()

void QwtKnob::setBorderWidth ( int borderWidth )

Set the knob's border width.

Parameters:

borderWidth new border width

void QwtKnob::setKnobStyle ( KnobStyle knobStyle )

Set the knob type.

Parameters:

knobStyle Knob type

See also:: knobStyle(), setBorderWidth()

void QwtKnob::setKnobWidth ( int width )

Change the knob's width.

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

Parameters:

width New width

void QwtKnob::setMarkerSize ( int size )

Set the size of the marker.

See also:: markerSize(), markerStyle()

void QwtKnob::setMarkerStyle ( MarkerStyle markerStyle )

Set the marker type of the knob.

Parameters:

markerStyle Marker type

See also:: markerStyle(), setMarkerSize()

void QwtAbstractSlider::setMass ( double val ) [virtual, inherited]

Set the slider's mass for flywheel effect.

If the slider's mass is greater then 0, it will continue to move after the mouse button has been released. Its speed decreases with time at a rate depending on the slider's mass. A large mass means that it will continue to move for a long time.

Derived widgets may overload this function to make it public.

Parameters:

val	New mass in kg

See also:: mass()

Reimplemented in QwtWheel.

void QwtAbstractSlider::setMouseOffset ( double offset ) [protected, inherited]

See also:: mouseOffset()

void QwtAbstractSlider::setOrientation ( Qt::Orientation o ) [virtual, inherited]

Set the orientation.

Parameters:

o	Orientation. Allowed values are Qt::Horizontal and Qt::Vertical.

Reimplemented in QwtSlider, and QwtWheel.

void QwtDoubleRange::setPeriodic ( bool tf ) [inherited]

Make the range periodic.

When the range is periodic, the value will be set to a point inside the interval such that

point = value + n * width

if the user tries to set a new value which is outside the range. If the range is nonperiodic (the default), values outside the range will be clipped.

Parameters:

tf	true for a periodic range

void QwtAbstractSlider::setPosition ( const QPoint & p ) [protected, virtual, inherited]

Move the slider to a specified point, adjust the value and emit signals if necessary.

void QwtDoubleRange::setRange	(	double	vmin,
		double	vmax,
		double	vstep = `0.0`,
		int	pageSize = `1`
	)		`[inherited]`

Specify range and step size.

Parameters:

vmin	lower boundary of the interval
vmax	higher boundary of the interval
vstep	step width
pageSize	page size in steps

Warning:

A change of the range changes the value if it lies outside the new range. The current value will *not* be adjusted to the new step raster.
vmax < vmin is allowed.
If the step size is left out or set to zero, it will be set to 1/100 of the interval length.
If the step size has an absurd value, it will be corrected to a better one.

void QwtAbstractSlider::setReadOnly ( bool readOnly ) [virtual, slot, inherited]

En/Disable read only mode

In read only mode the slider can't be controlled by mouse or keyboard.

Parameters:

readOnly Enables in case of true

See also:: isReadOnly()

void QwtAbstractScale::setScale	(	double	vmin,
		double	vmax,
		double	stepSize = `0.0`
	)		`[inherited]`

Specify a scale.

Disable autoscaling and define a scale by an interval and a step size

Parameters:

vmin	lower limit of the scale interval
vmax	upper limit of the scale interval
stepSize	major step size

    d_data->autoScale = false;
    d_data->stepSize = stepSize;

    rescale( vmin, vmax, stepSize );
    QwtAbstractScale *xx = new QwtAbstractScale(12, "hello", this);

See also:: setAutoScale()

void QwtAbstractScale::setScale	(	const QwtInterval &	interval,
		double	stepSize = `0.0`
	)		`[inherited]`

Specify a scale.

Disable autoscaling and define a scale by an interval and a step size

Parameters:

interval	Interval
stepSize	major step size

See also:: setAutoScale()

void QwtAbstractScale::setScale ( const QwtScaleDiv & scaleDiv ) [inherited]

Specify a scale.

Disable autoscaling and define a scale by a scale division

Parameters:

scaleDiv Scale division

See also:: setAutoScale()

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 QwtAbstractScale::setScaleEngine ( QwtScaleEngine * scaleEngine ) [inherited]

Set a scale engine.

The scale engine is responsible for calculating the scale division, and in case of auto scaling how to align the scale.

scaleEngine has to be created with new and will be deleted in ~QwtAbstractScale or the next call of setScaleEngine.

void QwtAbstractScale::setScaleMaxMajor ( int ticks ) [inherited]

Set the maximum number of major tick intervals.

The scale's major ticks are calculated automatically such that the number of major intervals does not exceed ticks. The default value is 5.

Parameters:

ticks maximal number of major ticks.

See also:: QwtAbstractScaleDraw

void QwtAbstractScale::setScaleMaxMinor ( int ticks ) [inherited]

Set the maximum number of minor tick intervals.

The scale's minor ticks are calculated automatically such that the number of minor intervals does not exceed ticks. The default value is 3.

Parameters:

ticks

See also:: QwtAbstractScaleDraw

void QwtDoubleRange::setStep ( double vstep ) [inherited]

Change the step raster.

Parameters:

vstep new step width

Warning:: The value will not be adjusted to the new step raster.

Reimplemented in QwtCounter.

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.

void QwtAbstractSlider::setTracking ( bool enable ) [inherited]

Enables or disables tracking.

If tracking is enabled, the slider emits a valueChanged() signal whenever its value changes (the default behaviour). If tracking is disabled, the value changed() signal will only be emitted if:

the user releases the mouse button and the value has changed or
at the end of automatic scrolling.

Tracking is enabled by default.

Parameters:

enable true (enable) or false (disable) tracking.

void QwtAbstractSlider::setUpdateTime ( int t ) [inherited]

Specify the update interval for automatic scrolling.

Parameters:

t	update interval in milliseconds

See also:: getScrollMode()

void QwtAbstractSlider::setValid ( bool valid ) [inline, inherited]

Parameters:

valid true/false

See also:: QwtDblRange::isValid()

Reimplemented from QwtDoubleRange.

void QwtAbstractSlider::setValue ( double val ) [virtual, slot, inherited]

Move the slider to a specified value.

This function can be used to move the slider to a value which is not an integer multiple of the step size.

Parameters:

val new value

See also:: fitValue()

Reimplemented from QwtDoubleRange.

QSize QwtKnob::sizeHint ( ) const [virtual]

Returns:: minimumSizeHint()

void QwtAbstractSlider::sliderMoved ( double value ) [signal, inherited]

This signal is emitted when the user moves the slider with the mouse.

Parameters:

value new value

void QwtAbstractSlider::sliderPressed ( ) [signal, inherited]

This signal is emitted when the user presses the movable part of the slider (start ScrMouse Mode).

void QwtAbstractSlider::sliderReleased ( ) [signal, inherited]

This signal is emitted when the user releases the movable part of the slider.

double QwtDoubleRange::step ( ) const [inherited]

Returns:: the step size

See also:: setStep(), setRange()

Reimplemented in QwtCounter.

void QwtDoubleRange::stepChange ( ) [protected, virtual, inherited]

Notify a change of the step size.

This virtual function is called whenever the step size changes. The default implementation does nothing.

void QwtAbstractSlider::stopMoving ( ) [inherited]

Stop updating if automatic scrolling is active.

void QwtAbstractSlider::timerEvent ( QTimerEvent * e ) [protected, virtual, inherited]

Qt timer event

Parameters:

e	Timer event

double QwtKnob::totalAngle ( ) const

Return the total angle.

double QwtDoubleRange::value ( ) const [inherited]

Returns the current value.

Reimplemented in QwtCounter.

void QwtAbstractSlider::valueChanged ( double value ) [signal, inherited]

Notify a change of value.

In the default setting (tracking enabled), this signal will be emitted every time the value changes ( see setTracking() ).

Parameters:

value new value

void QwtAbstractSlider::wheelEvent ( QWheelEvent * e ) [protected, virtual, inherited]

Wheel Event handler

Parameters:

e	Whell event

Public Types

Public Slots

Signals

Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation