QwtDial class provides a rounded range control. More...

#include <qwt_dial.h>

Inheritance diagram for QwtDial:

Classes
class	PrivateData

Public Types
enum	Shadow { Plain = QFrame::Plain , Raised = QFrame::Raised , Sunken = QFrame::Sunken }
	Frame shadow. More...

enum	Mode { RotateNeedle , RotateScale }
	Mode controlling whether the needle or the scale is rotating. More...

Public Member Functions
	QwtDial (QWidget *parent=NULL)
	Constructor.

virtual	~QwtDial ()
	Destructor.

void	setFrameShadow (Shadow)
	Sets the frame shadow value from the frame style.

Shadow	frameShadow () const

void	setLineWidth (int)
	Sets the line width of the frame.

int	lineWidth () const

void	setMode (Mode)
	Change the mode of the dial.

Mode	mode () const

void	setScaleArc (double minArc, double maxArc)
	Change the arc of the scale.

void	setMinScaleArc (double)
	Set the lower limit for the scale arc.

double	minScaleArc () const

void	setMaxScaleArc (double)
	Set the upper limit for the scale arc.

double	maxScaleArc () const

virtual void	setOrigin (double)
	Change the origin.

double	origin () const
	The origin is the angle where scale and needle is relative to.

void	setNeedle (QwtDialNeedle *)
	Set a needle for the dial.

const QwtDialNeedle *	needle () const

QwtDialNeedle *	needle ()

QRect	boundingRect () const

QRect	innerRect () const

virtual QRect	scaleInnerRect () const

virtual QSize	sizeHint () const QWT_OVERRIDE

virtual QSize	minimumSizeHint () const QWT_OVERRIDE

void	setScaleDraw (QwtRoundScaleDraw *)
	Set an individual scale draw.

QwtRoundScaleDraw *	scaleDraw ()

const QwtRoundScaleDraw *	scaleDraw () const

Public Member Functions inherited from QwtAbstractSlider
	QwtAbstractSlider (QWidget *parent=NULL)
	Constructor.

virtual	~QwtAbstractSlider ()
	Destructor.

void	setValid (bool)
	Set the value to be valid/invalid.

bool	isValid () const

double	value () const
	Returns the current value.

void	setWrapping (bool)
	If wrapping is true stepping up from upperBound() value will take you to the minimum() value and vice versa.

bool	wrapping () const

void	setTotalSteps (uint)
	Set the number of steps.

uint	totalSteps () const

void	setSingleSteps (uint)
	Set the number of steps for a single increment.

uint	singleSteps () const

void	setPageSteps (uint)
	Set the number of steps for a page increment.

uint	pageSteps () const

void	setStepAlignment (bool)
	Enable step alignment.

bool	stepAlignment () const

void	setTracking (bool)
	Enables or disables tracking.

bool	isTracking () const

void	setReadOnly (bool)
	En/Disable read only mode.

bool	isReadOnly () const
	In read only mode the slider can't be controlled by mouse or keyboard.

void	setInvertedControls (bool)
	Invert wheel and key events.

bool	invertedControls () const

Public Member Functions inherited from QwtAbstractScale
	QwtAbstractScale (QWidget *parent=NULL)
	Constructor.

virtual	~QwtAbstractScale ()
	Destructor.

void	setScale (double lowerBound, double upperBound)
	Specify a scale.

void	setScale (const QwtInterval &)
	Specify a scale.

void	setScale (const QwtScaleDiv &)
	Specify a scale.

const QwtScaleDiv &	scaleDiv () const

void	setLowerBound (double value)
	Set the lower bound of the scale.

double	lowerBound () const

void	setUpperBound (double value)
	Set the upper bound of the scale.

double	upperBound () const

void	setScaleStepSize (double stepSize)
	Set the step size used for calculating a scale division.

double	scaleStepSize () const

void	setScaleMaxMajor (int ticks)
	Set the maximum number of major tick intervals.

int	scaleMaxMinor () const

void	setScaleMaxMinor (int ticks)
	Set the maximum number of minor tick intervals.

int	scaleMaxMajor () const

void	setScaleEngine (QwtScaleEngine *)
	Set a scale engine.

const QwtScaleEngine *	scaleEngine () const

QwtScaleEngine *	scaleEngine ()

int	transform (double) const
	Translate a scale value into a widget coordinate.

double	invTransform (int) const
	Translate a widget coordinate into a scale value.

bool	isInverted () const

double	minimum () const

double	maximum () const

const QwtScaleMap &	scaleMap () const

Protected Member Functions
virtual void	wheelEvent (QWheelEvent *) QWT_OVERRIDE
	Wheel Event handler.

virtual void	paintEvent (QPaintEvent *) QWT_OVERRIDE
	Paint the dial.

virtual void	changeEvent (QEvent *) QWT_OVERRIDE
	Change Event handler.

virtual void	drawFrame (QPainter *)
	Draw the frame around the dial.

virtual void	drawContents (QPainter *) const
	Draw the contents inside the frame.

virtual void	drawFocusIndicator (QPainter *) const
	Draw the focus indicator.

void	invalidateCache ()
	Invalidate the internal caches used to speed up repainting.

virtual void	drawScale (QPainter *, const QPointF &center, double radius) const
	Draw the scale.

virtual void	drawScaleContents (QPainter *painter, const QPointF &center, double radius) const
	Draw the contents inside the scale.

virtual void	drawNeedle (QPainter *, const QPointF &, double radius, double direction, QPalette::ColorGroup) const
	Draw the needle.

virtual double	scrolledTo (const QPoint &) const QWT_OVERRIDE
	Determine the value for a new position of the slider handle.

virtual bool	isScrollPosition (const QPoint &) const QWT_OVERRIDE
	Determine what to do when the user presses a mouse button.

virtual void	sliderChange () QWT_OVERRIDE
	Calling update()

virtual void	scaleChange () QWT_OVERRIDE
	Invalidate the internal caches and call QwtAbstractSlider::scaleChange()

Protected Member Functions inherited from QwtAbstractSlider
virtual void	mousePressEvent (QMouseEvent *) QWT_OVERRIDE
	Mouse press event handler.

virtual void	mouseReleaseEvent (QMouseEvent *) QWT_OVERRIDE
	Mouse Release Event handler.

virtual void	mouseMoveEvent (QMouseEvent *) QWT_OVERRIDE
	Mouse Move Event handler.

virtual void	keyPressEvent (QKeyEvent *) QWT_OVERRIDE
	Handles key events.

void	incrementValue (int stepCount)
	Increment the slider.

double	incrementedValue (double value, int stepCount) const
	Increment a value.

Protected Member Functions inherited from QwtAbstractScale
void	rescale (double lowerBound, double upperBound, double stepSize)
	Recalculate the scale division and update the scale.

void	setAbstractScaleDraw (QwtAbstractScaleDraw *)
	Set a scale draw.

const QwtAbstractScaleDraw *	abstractScaleDraw () const

QwtAbstractScaleDraw *	abstractScaleDraw ()

void	updateScaleDraw ()
	Recalculate ticks and scale boundaries.

Properties
int	lineWidth

Shadow	frameShadow

Mode	mode

double	origin

double	minScaleArc

double	maxScaleArc

Properties inherited from QwtAbstractSlider
double	value

uint	totalSteps

uint	singleSteps

uint	pageSteps

bool	stepAlignment

bool	readOnly

bool	tracking

bool	wrapping

bool	invertedControls

Properties inherited from QwtAbstractScale
double	lowerBound

double	upperBound

int	scaleMaxMajor

int	scaleMaxMinor

double	scaleStepSize

Additional Inherited Members
Public Slots inherited from QwtAbstractSlider
void	setValue (double value)
	Set the slider to the specified value.

Signals inherited from QwtAbstractSlider
void	valueChanged (double value)
	Notify a change of value.

void	sliderPressed ()
	This signal is emitted when the user presses the movable part of the slider.

void	sliderReleased ()
	This signal is emitted when the user releases the movable part of the slider.

void	sliderMoved (double value)
	This signal is emitted when the user moves the slider with the mouse.

Detailed Description

QwtDial class provides a rounded range control.

QwtDial is intended as base class for dial widgets like speedometers, compass widgets, clocks ...

A dial contains a scale and a needle indicating the current value of the dial. Depending on Mode one of them is fixed and the other is rotating. If not isReadOnly() the dial can be rotated by dragging the mouse or using keyboard inputs (see QwtAbstractSlider::keyPressEvent()). A dial might be wrapping, what means a rotation below/above one limit continues on the other limit (f.e compass). The scale might cover any arc of the dial, its values are related to the origin() of the dial.

Often dials have to be updated very often according to values from external devices. For these high refresh rates QwtDial caches as much as possible. For derived classes it might be necessary to clear these caches manually according to attribute changes using invalidateCache().

See also: QwtCompass, QwtAnalogClock, QwtDialNeedle

Note: The controls and dials examples shows different types of dials.; QDial is more similar to QwtKnob than to QwtDial

Member Enumeration Documentation

◆ Mode

enum QwtDial::Mode

Mode controlling whether the needle or the scale is rotating.

Enumerator
RotateNeedle	The needle is rotating.
RotateScale	The needle is fixed, the scales are rotating.

◆ Shadow

enum QwtDial::Shadow

Frame shadow.

Unfortunately it is not possible to use QFrame::Shadow as a property of a widget that is not derived from QFrame. The following enum is made for the designer only. It is safe to use QFrame::Shadow instead.

Enumerator
Plain	QFrame::Plain.
Raised	QFrame::Raised.
Sunken	QFrame::Sunken.

Constructor & Destructor Documentation

◆ QwtDial()

QwtDial::QwtDial ( QWidget * parent = NULL )

explicit

Constructor.

Parameters

parent Parent widget

Create a dial widget with no needle. The scale is initialized to [ 0.0, 360.0 ] and 360 steps ( QwtAbstractSlider::setTotalSteps() ). The origin of the scale is at 90°,

The value is set to 0.0.

The default mode is QwtDial::RotateNeedle.

Member Function Documentation

◆ boundingRect()

QRect QwtDial::boundingRect ( ) const

Returns: bounding rectangle of the dial including the frame

See also: setLineWidth(), scaleInnerRect(), innerRect()

◆ changeEvent()

void QwtDial::changeEvent ( QEvent * event )

protectedvirtual

Change Event handler.

Parameters

event Change event

Invalidates internal paint caches if necessary

Reimplemented from QwtAbstractScale.

◆ drawContents()

void QwtDial::drawContents ( QPainter * painter ) const

protectedvirtual

Draw the contents inside the frame.

QPalette::Window is the background color outside of the frame. QPalette::Base is the background color inside the frame. QPalette::WindowText is the background color inside the scale.

Parameters

painter Painter

See also: boundingRect(), innerRect(), scaleInnerRect(), QWidget::setPalette()

◆ drawFocusIndicator()

void QwtDial::drawFocusIndicator ( QPainter * painter ) const

protectedvirtual

Draw the focus indicator.

Parameters

painter Painter

◆ drawFrame()

void QwtDial::drawFrame ( QPainter * painter )

protectedvirtual

Draw the frame around the dial.

Parameters

painter Painter

See also: lineWidth(), frameShadow()

◆ drawNeedle()

void QwtDial::drawNeedle	(	QPainter *	painter,
		const QPointF &	center,
		double	radius,
		double	direction,
		QPalette::ColorGroup	colorGroup
	)		const

protectedvirtual

Draw the needle.

Parameters

painter	Painter
center	Center of the dial
radius	Length for the needle
direction	Direction of the needle in degrees, counter clockwise
colorGroup	ColorGroup

Reimplemented in QwtAnalogClock.

◆ drawScale()

void QwtDial::drawScale	(	QPainter *	painter,
		const QPointF &	center,
		double	radius
	)		const

protectedvirtual

Draw the scale.

Parameters

painter	Painter
center	Center of the dial
radius	Radius of the scale

◆ drawScaleContents()

void QwtDial::drawScaleContents	(	QPainter *	painter,
		const QPointF &	center,
		double	radius
	)		const

protectedvirtual

Draw the contents inside the scale.

Paints nothing.

Parameters

painter	Painter
center	Center of the contents circle
radius	Radius of the contents circle

Reimplemented in QwtCompass.

◆ frameShadow()

QwtDial::Shadow QwtDial::frameShadow ( ) const

Returns: Frame shadow /sa setFrameShadow(), lineWidth(), QFrame::frameShadow()

◆ innerRect()

QRect QwtDial::innerRect ( ) const

Returns: bounding rectangle of the circle inside the frame

See also: setLineWidth(), scaleInnerRect(), boundingRect()

◆ isScrollPosition()

bool QwtDial::isScrollPosition ( const QPoint & pos ) const

protectedvirtual

Determine what to do when the user presses a mouse button.

Parameters

pos	Mouse position

Return values

True,when the inner circle contains pos

See also: scrolledTo()

Implements QwtAbstractSlider.

◆ lineWidth()

int QwtDial::lineWidth ( ) const

Returns: Line width of the frame

See also: setLineWidth(), frameShadow(), lineWidth()

◆ maxScaleArc()

double QwtDial::maxScaleArc ( ) const

Returns: Upper limit of the scale arc

See also: setScaleArc()

◆ minimumSizeHint()

QSize QwtDial::minimumSizeHint ( ) const

virtual

Returns: Minimum size hint

See also: sizeHint()

◆ minScaleArc()

double QwtDial::minScaleArc ( ) const

Returns: Lower limit of the scale arc

See also: setScaleArc()

◆ mode()

QwtDial::Mode QwtDial::mode ( ) const

Returns: Mode of the dial.

See also: setMode(), origin(), setScaleArc(), value()

◆ needle() [1/2]

QwtDialNeedle * QwtDial::needle ( )

Returns: needle

See also: setNeedle()

◆ needle() [2/2]

const QwtDialNeedle * QwtDial::needle ( ) const

Returns: needle

See also: setNeedle()

◆ origin()

double QwtDial::origin ( ) const

The origin is the angle where scale and needle is relative to.

Returns: Origin of the dial

See also: setOrigin()

◆ paintEvent()

void QwtDial::paintEvent ( QPaintEvent * event )

protectedvirtual

Paint the dial.

Parameters

event Paint event

◆ scaleChange()

void QwtDial::scaleChange ( )

protectedvirtual

Invalidate the internal caches and call QwtAbstractSlider::scaleChange()

Reimplemented from QwtAbstractSlider.

◆ scaleDraw() [1/2]

QwtRoundScaleDraw * QwtDial::scaleDraw ( )

Returns: the scale draw

◆ scaleDraw() [2/2]

const QwtRoundScaleDraw * QwtDial::scaleDraw ( ) const

Returns: the scale draw

◆ scaleInnerRect()

QRect QwtDial::scaleInnerRect ( ) const

virtual

Returns: rectangle inside the scale

See also: setLineWidth(), boundingRect(), innerRect()

◆ scrolledTo()

double QwtDial::scrolledTo ( const QPoint & pos ) const

protectedvirtual

Determine the value for a new position of the slider handle.

Parameters

pos	Mouse position

Returns: Value for the mouse position

See also: isScrollPosition()

Implements QwtAbstractSlider.

◆ setFrameShadow()

void QwtDial::setFrameShadow ( Shadow shadow )

Sets the frame shadow value from the frame style.

Parameters

shadow Frame shadow

See also: setLineWidth(), QFrame::setFrameShadow()

◆ setLineWidth()

void QwtDial::setLineWidth ( int lineWidth )

Sets the line width of the frame.

Parameters

lineWidth Line width

See also: setFrameShadow()

◆ setMaxScaleArc()

void QwtDial::setMaxScaleArc ( double max )

Set the upper limit for the scale arc.

Parameters

max	Upper limit of the scale arc

See also: setScaleArc(), setMinScaleArc()

◆ setMinScaleArc()

void QwtDial::setMinScaleArc ( double min )

Set the lower limit for the scale arc.

Parameters

min	Lower limit of the scale arc

See also: setScaleArc(), setMaxScaleArc()

◆ setMode()

void QwtDial::setMode ( Mode mode )

Change the mode of the dial.

Parameters

mode New mode

In case of QwtDial::RotateNeedle the needle is rotating, in case of QwtDial::RotateScale, the needle points to origin() and the scale is rotating.

The default mode is QwtDial::RotateNeedle.

See also: mode(), setValue(), setOrigin()

◆ setNeedle()

void QwtDial::setNeedle ( QwtDialNeedle * needle )

Set a needle for the dial.

Parameters

needle Needle

Warning: The needle will be deleted, when a different needle is set or in ~QwtDial()

◆ setOrigin()

void QwtDial::setOrigin ( double origin )

virtual

Change the origin.

The origin is the angle where scale and needle is relative to.

Parameters

origin New origin

See also: origin()

◆ setScaleArc()

void QwtDial::setScaleArc	(	double	minArc,
		double	maxArc
	)

Change the arc of the scale.

Parameters

minArc	Lower limit
maxArc	Upper limit

See also: minScaleArc(), maxScaleArc()

◆ setScaleDraw()

void QwtDial::setScaleDraw ( QwtRoundScaleDraw * scaleDraw )

Set an individual scale draw.

The motivation for setting a scale draw is often to overload QwtRoundScaleDraw::label() to return individual tick labels.

Parameters

scaleDraw Scale draw

Warning: The previous scale draw is deleted

◆ sizeHint()

QSize QwtDial::sizeHint ( ) const

virtual

Returns: Size hint

See also: minimumSizeHint()

◆ sliderChange()

void QwtDial::sliderChange ( )

protectedvirtual

Calling update()

Reimplemented from QwtAbstractSlider.

◆ wheelEvent()

void QwtDial::wheelEvent ( QWheelEvent * event )

protectedvirtual

Wheel Event handler.

Parameters

event Wheel event

Reimplemented from QwtAbstractSlider.

The documentation for this class was generated from the following files:

/home/runner/work/QWT/QWT/src/qwt_dial.h
/home/runner/work/QWT/QWT/src/qwt_dial.cpp

Classes

Public Types

Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ Mode

◆ Shadow

Constructor & Destructor Documentation

◆ QwtDial()

Member Function Documentation

◆ boundingRect()

◆ changeEvent()

◆ drawContents()

◆ drawFocusIndicator()

◆ drawFrame()

◆ drawNeedle()

◆ drawScale()

◆ drawScaleContents()

◆ frameShadow()

◆ innerRect()

◆ isScrollPosition()

◆ lineWidth()

◆ maxScaleArc()

◆ minimumSizeHint()

◆ minScaleArc()

◆ mode()

◆ needle() [1/2]

◆ needle() [2/2]

◆ origin()

◆ paintEvent()

◆ scaleChange()

◆ scaleDraw() [1/2]

◆ scaleDraw() [2/2]

◆ scaleInnerRect()

◆ scrolledTo()

◆ setFrameShadow()

◆ setLineWidth()

◆ setMaxScaleArc()

◆ setMinScaleArc()

◆ setMode()

◆ setNeedle()

◆ setOrigin()

◆ setScaleArc()

◆ setScaleDraw()

◆ sizeHint()

◆ sliderChange()

◆ wheelEvent()