SYNOPSIS
#include <qwt_analog_clock.h>
Inherits QwtDial.
Public Types
enum Direction { Clockwise, CounterClockwise }
enum Hand { SecondHand, MinuteHand, HourHand, NHands }
enum Mode { RotateNeedle, RotateScale }
enum ScaleOptions { ScaleBackbone = 1, ScaleTicks = 2, ScaleLabel = 4 }
enum ScrollMode { ScrNone, ScrMouse, ScrTimer, ScrDirect, ScrPage }
enum Shadow { Plain = QFrame::Plain, Raised = QFrame::Raised, Sunken = QFrame::Sunken }
Public Slots
virtual void fitValue (double val)
virtual void incValue (int steps)
void setCurrentTime ()
virtual void setReadOnly (bool)
void setTime (const QTime &=QTime::currentTime())
virtual void setValue (double val)
Signals
void sliderMoved (double value)
void sliderPressed ()
void sliderReleased ()
void valueChanged (double value)
Public Member Functions
QRect boundingRect () const
QRect contentsRect () const
Direction direction () const
Shadow frameShadow () const
QwtDialNeedle * hand (Hand)
const QwtDialNeedle * hand (Hand) const
bool hasVisibleBackground () const
virtual void incPages (int)
bool isReadOnly () const
bool isValid () const
int lineWidth () const
virtual double mass () const
double maxScaleArc () const
double maxValue () const
virtual QSize minimumSizeHint () const
double minScaleArc () const
double minValue () const
Mode mode () const
const QwtDialNeedle * needle () const
QwtDialNeedle * needle ()
Qt::Orientation orientation () const
double origin () const
int pageSize () const
bool periodic () const
QwtAnalogClock (QWidget *parent=NULL)
virtual QRect scaleContentsRect () const
QwtDialScaleDraw * scaleDraw ()
const QwtDialScaleDraw * scaleDraw () const
void setDirection (Direction)
void setFrameShadow (Shadow)
virtual void setHand (Hand, QwtDialNeedle *)
void setLineWidth (int)
virtual void setMass (double val)
void setMode (Mode)
virtual void setOrientation (Qt::Orientation o)
virtual void setOrigin (double)
void setPeriodic (bool tf)
void setRange (double vmin, double vmax, double vstep=0.0, int pagesize=1)
virtual void setScale (int maxMajIntv, int maxMinIntv, double step=0.0)
void setScaleArc (double min, double max)
virtual void setScaleDraw (QwtDialScaleDraw *)
void setScaleOptions (int)
void setScaleTicks (int minLen, int medLen, int majLen, int penWidth=1)
void setStep (double)
void setTracking (bool enable)
void setUpdateTime (int t)
void setValid (bool valid)
virtual void setWrapping (bool)
void showBackground (bool)
virtual QSize sizeHint () const
double step () const
void stopMoving ()
double value () const
bool wrapping () const
virtual ~QwtAnalogClock ()
Protected Member Functions
virtual void drawContents (QPainter *) const
virtual void drawFocusIndicator (QPainter *) const
virtual void drawFrame (QPainter *p)
virtual void drawHand (QPainter *, Hand, const QPoint &, int radius, double direction, QPalette::ColorGroup) const
virtual void drawNeedle (QPainter *, const QPoint &, int radius, double direction, QPalette::ColorGroup) const
virtual void drawScale (QPainter *, const QPoint ¢er, int radius, double origin, double arcMin, double arcMax) const
virtual void drawScaleContents (QPainter *painter, const QPoint ¢er, int radius) const
double exactPrevValue () const
double exactValue () const
virtual void getScrollMode (const QPoint &, int &scrollMode, int &direction)
virtual double getValue (const QPoint &)
virtual void keyPressEvent (QKeyEvent *)
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
virtual void rangeChange ()
virtual void resizeEvent (QResizeEvent *)
virtual QwtText scaleLabel (double) const
int scrollMode () const
void setMouseOffset (double)
virtual void setPosition (const QPoint &)
virtual void stepChange ()
virtual void timerEvent (QTimerEvent *e)
virtual void updateMask ()
void updateScale ()
virtual void valueChange ()
virtual void wheelEvent (QWheelEvent *e)
Detailed Description
An analog clock.
Example
-
#include <qwt_analog_clock.h> QwtAnalogClock *clock = new QwtAnalogClock(...); clock->scaleDraw()->setPenWidth(3); clock->setLineWidth(6); clock->setFrameShadow(QwtDial::Sunken); clock->setTime(); // update the clock every second QTimer *timer = new QTimer(clock); timer->connect(timer, SIGNAL(timeout()), clock, SLOT(setCurrentTime())); timer->start(1000);
Qwt is missing a set of good looking hands. Contributions are very welcome.
Note:
- The examples/dials example shows how to use QwtAnalogClock.
Member Enumeration Documentation
enum QwtDial::Direction [inherited]Direction of the dial
enum QwtAnalogClock::HandHand type
See also:
- setHand(), hand()
enum QwtDial::Mode [inherited]In case of RotateNeedle the needle is rotating, in case of RotateScale, the needle points to origin() and the scale is rotating.
enum QwtDial::ScaleOptions [inherited]
see QwtDial::setScaleOptions
enum QwtAbstractSlider::ScrollMode [inherited]Scroll mode
See also:
- getScrollMode()
enum QwtDial::Shadow [inherited]
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.
Constructor & Destructor Documentation
QwtAnalogClock::QwtAnalogClock (QWidget *parent = NULL) [explicit]Constructor
Parameters:
- parent Parent widget
QwtAnalogClock::~QwtAnalogClock () [virtual]
Destructor.
Member Function Documentation
QRect QwtDial::boundingRect () const [inherited]Returns:
- bounding rect of the dial including the frame
See also:
- setLineWidth(), scaleContentsRect(), contentsRect()
QRect QwtDial::contentsRect () const [inherited]Returns:
- bounding rect of the circle inside the frame
See also:
- setLineWidth(), scaleContentsRect(), boundingRect()
QwtDial::Direction QwtDial::direction () const [inherited]Returns:
- Direction of the dial
The default direction of a dial is QwtDial::Clockwise
See also:
- setDirection()
void QwtDial::drawContents (QPainter *painter) const [protected, virtual, inherited]
Draw the contents inside the frame. QColorGroup::Background is the background color outside of the frame. QColorGroup::Base is the background color inside the frame. QColorGroup::Foreground is the background color inside the scale.
Parameters:
- painter Painter
See also:
- boundingRect(), contentsRect(), scaleContentsRect(), QWidget::setPalette()
void QwtDial::drawFocusIndicator (QPainter *painter) const [protected, virtual, inherited]Draw a dotted round circle, if !isReadOnly()
Parameters:
- painter Painter
void QwtDial::drawFrame (QPainter *painter) [protected, virtual, inherited]Draw the frame around the dial
Parameters:
- painter Painter
See also:
- lineWidth(), frameShadow()
void QwtAnalogClock::drawHand (QPainter *painter, Handhd, const QPoint ¢er, intradius, doubledirection, QPalette::ColorGroupcg) const [protected, virtual]Draw a clock hand
Parameters:
-
painter Painter
hd Specify the type of hand
center Center of the clock
radius Maximum length for the hands
direction Direction of the hand in degrees, counter clockwise
cg ColorGroup
void QwtAnalogClock::drawNeedle (QPainter *painter, const QPoint ¢er, intradius, doubledirection, QPalette::ColorGroupcg) const [protected, virtual]
Draw the needle. A clock has no single needle but three hands instead. drawNeedle translates value() into directions for the hands and calls drawHand().
Parameters:
-
painter Painter
center Center of the clock
radius Maximum length for the hands
direction Dummy, not used.
cg ColorGroup
See also:
- drawHand()
Reimplemented from QwtDial.
void QwtDial::drawScale (QPainter *painter, const QPoint ¢er, intradius, doubleorigin, doubleminArc, doublemaxArc) const [protected, virtual, inherited]Draw the scale
Parameters:
-
painter Painter
center Center of the dial
radius Radius of the scale
origin Origin of the scale
minArc Minimum of the arc
maxArc Minimum of the arc
See also:
- QwtAbstractScaleDraw::setAngleRange()
void QwtDial::drawScaleContents (QPainter *painter, const QPoint ¢er, intradius) const [protected, virtual, inherited]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.
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 QwtDoubleRange::fitValue or QwtDoubleRange::incValue have been used before. This function is intended for internal use in derived classes.
void QwtAbstractSlider::fitValue (doublevalue) [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.
QwtDial::Shadow QwtDial::frameShadow () const [inherited]Returns:
- Frame shadow /sa setFrameShadow(), lineWidth(), QFrame::frameShadow
void QwtDial::getScrollMode (const QPoint &pos, int &scrollMode, int &direction) [protected, virtual, inherited]See QwtAbstractSlider::getScrollMode()
Parameters:
- pos point where the mouse was pressed
Return values:
-
scrollMode The scrolling mode
direction direction: 1, 0, or -1.
See also:
- QwtAbstractSlider::getScrollMode()
Implements QwtAbstractSlider.
double QwtDial::getValue (const QPoint &pos) [protected, virtual, inherited]Find the value for a given position
Parameters:
- pos Position
Returns:
- Value
Implements QwtAbstractSlider.
QwtDialNeedle * QwtAnalogClock::hand (Handhd)Returns:
- Clock hand
Parameters:
- hd Specifies the type of hand
See also:
- setHand()
const QwtDialNeedle * QwtAnalogClock::hand (Handhd) constReturns:
- Clock hand
Parameters:
- hd Specifies the type of hand
See also:
- setHand()
bool QwtDial::hasVisibleBackground () const [inherited]true when the area outside of the frame is visible
See also:
- showBackground(), setMask()
void QwtDoubleRange::incPages (intnPages) [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 (intsteps) [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 QwtDial::keyPressEvent (QKeyEvent *event) [protected, virtual, inherited]Handles key events
-
Key_Down, KeyLeft
Decrement by 1 -
Key_Prior
Decrement by pageSize() -
Key_Home
Set the value to minValue()
-
Key_Up, KeyRight
Increment by 1 -
Key_Next
Increment by pageSize() -
Key_End
Set the value to maxValue()
Parameters:
- event Key event
See also:
- isReadOnly()
Reimplemented from QwtAbstractSlider.
Reimplemented in QwtCompass.
int QwtDial::lineWidth () const [inherited]Returns:
- Line width of the frame
See also:
- setLineWidth(), frameShadow(), lineWidth()
double QwtAbstractSlider::mass () const [virtual, inherited]Returns:
- mass
See also:
- setMass()
Reimplemented in QwtWheel.
double QwtDial::maxScaleArc () const [inherited]Returns:
- Upper limit of the scale arc
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()
QSize QwtDial::minimumSizeHint () const [virtual, inherited]
Return a minimum size hint. Warning:
- The return value of QwtDial::minimumSizeHint() depends on the font and the scale.
double QwtDial::minScaleArc () const [inherited]Returns:
- Lower limit of the scale arc
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()
QwtDial::Mode QwtDial::mode () const [inherited]Returns:
- mode of the dial.
The value of the dial is indicated by the difference between the origin and the direction of the needle. In case of QwtDial::RotateNeedle the scale arc is fixed to the origin() and 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:
- setMode(), origin(), setScaleArc(), value()
void QwtAbstractSlider::mouseMoveEvent (QMouseEvent *e) [protected, virtual, inherited]Mouse Move Event handler
Parameters:
- e Mouse event
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
const QwtDialNeedle * QwtDial::needle () const [inherited]Returns:
- needle
See also:
- setNeedle()
QwtDialNeedle * QwtDial::needle () [inherited]Returns:
- needle
See also:
- setNeedle()
Qt::Orientation QwtAbstractSlider::orientation () const [inherited]Returns:
- Orientation
See also:
- setOrientation()
double QwtDial::origin () const [inherited]The origin is the angle where scale and needle is relative to.
Returns:
- Origin of the dial
See also:
- setOrigin()
int QwtDoubleRange::pageSize () const [inherited]
Returns the page size in steps.
void QwtDial::paintEvent (QPaintEvent *e) [protected, virtual, inherited]Paint the dial
Parameters:
- e 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 QwtDial::rangeChange () [protected, virtual, inherited]
QwtDoubleRange update hook.
Reimplemented from QwtDoubleRange.
void QwtDial::resizeEvent (QResizeEvent *e) [protected, virtual, inherited]Resize the dial widget
Parameters:
- e Resize event
QRect QwtDial::scaleContentsRect () const [virtual, inherited]Returns:
- rect inside the scale
See also:
- setLineWidth(), boundingRect(), contentsRect()
QwtDialScaleDraw * QwtDial::scaleDraw () [inherited]
Return the scale draw.
const QwtDialScaleDraw * QwtDial::scaleDraw () const [inherited]
Return the scale draw.
QwtText QwtAnalogClock::scaleLabel (doublevalue) const [protected, virtual]Find the scale label for a given value
Parameters:
- value Value
Returns:
- Label
Reimplemented from QwtDial.
void QwtAnalogClock::setCurrentTime () [slot]
Set the current time. This is the same as QwtAnalogClock::setTime(), but Qt < 3.0 can't handle default parameters for slots.
void QwtDial::setDirection (Directiondirection) [inherited]Set the direction of the dial (clockwise/counterclockwise)
Direction direction
See also:
- direction()
void QwtDial::setFrameShadow (Shadowshadow) [inherited]Sets the frame shadow value from the frame style.
Parameters:
- shadow Frame shadow
See also:
- setLineWidth(), QFrame::setFrameShadow()
void QwtAnalogClock::setHand (Handhand, QwtDialNeedle *needle) [virtual]Set a clockhand
Parameters:
-
hand Specifies the type of hand
needle Hand
See also:
- hand()
void QwtDial::setLineWidth (intlineWidth) [inherited]Sets the line width
Parameters:
- lineWidth Line width
See also:
- setFrameShadow()
void QwtAbstractSlider::setMass (doubleval) [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 QwtDial::setMode (Modemode) [inherited]
Change the mode of the meter. Parameters:
- mode New mode
The value of the meter is indicated by the difference between north of the scale and the direction of the needle. In case of QwtDial::RotateNeedle north is pointing to the origin() and 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()
void QwtAbstractSlider::setOrientation (Qt::Orientationo) [virtual, inherited]
Set the orientation. Parameters:
- o Orientation. Allowed values are Qt::Horizontal and Qt::Vertical.
Reimplemented in QwtSlider, and QwtWheel.
void QwtDial::setOrigin (doubleorigin) [virtual, inherited]
Change the origin. The origin is the angle where scale and needle is relative to.
Parameters:
- origin New origin
See also:
- origin()
void QwtDoubleRange::setPeriodic (booltf) [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 .fi 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 (doublevmin, doublevmax, doublevstep = 0.0, intpageSize = 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 (boolreadOnly) [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 QwtDial::setScale (intmaxMajIntv, intmaxMinIntv, doublestep = 0.0) [virtual, inherited]Change the intervals of the scale
See also:
- QwtAbstractScaleDraw::setScale()
void QwtDial::setScaleArc (doubleminArc, doublemaxArc) [inherited]Change the arc of the scale
Parameters:
-
minArc Lower limit
maxArc Upper limit
void QwtDial::setScaleDraw (QwtDialScaleDraw *scaleDraw) [virtual, inherited]Set an individual scale draw
Parameters:
- scaleDraw Scale draw
Warning:
- The previous scale draw is deleted
void QwtDial::setScaleOptions (intoptions) [inherited]A wrapper method for accessing the scale draw.
-
options == 0
No visible scale: setScaleDraw(NULL) -
options & ScaleBackbone
En/disable the backbone of the scale. -
options & ScaleTicks
En/disable the ticks of the scale. -
options & ScaleLabel
En/disable scale labels
See also:
- QwtAbstractScaleDraw::enableComponent()
void QwtDial::setScaleTicks (intminLen, intmedLen, intmajLen, intpenWidth = 1) [inherited]Assign length and width of the ticks
Parameters:
-
minLen Length of the minor ticks
medLen Length of the medium ticks
majLen Length of the major ticks
penWidth Width of the pen for all ticks
See also:
- QwtAbstractScaleDraw::setTickLength(), QwtDialScaleDraw::setPenWidth()
void QwtDoubleRange::setStep (doublevstep) [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 QwtAnalogClock::setTime (const QTime &time = QTime::currentTime()) [slot]Set a time
Parameters:
- time Time to display
void QwtAbstractSlider::setTracking (boolenable) [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 (intt) [inherited]
Specify the update interval for automatic scrolling. Parameters:
- t update interval in milliseconds
See also:
- getScrollMode()
void QwtAbstractSlider::setValid (boolvalid) [inline, inherited]Parameters:
- valid true/false
See also:
- QwtDblRange::isValid()
Reimplemented from QwtDoubleRange.
void QwtAbstractSlider::setValue (doubleval) [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.
void QwtDial::setWrapping (boolwrapping) [virtual, inherited]Sets whether it is possible to step the value from the highest value to the lowest value and vice versa to on.
Parameters:
- wrapping en/disables wrapping
See also:
- wrapping(), QwtDoubleRange::periodic()
Note:
- The meaning of wrapping is like the wrapping property of QSpinBox, but not like it is used in QDial.
void QwtDial::showBackground (boolshow) [inherited]Show/Hide the area outside of the frame
Parameters:
- show Show if true, hide if false
See also:
- hasVisibleBackground(), setMask()
Warning:
- When QwtDial is a toplevel widget the window border might disappear too.
QSize QwtDial::sizeHint () const [virtual, inherited]Returns:
- Size hint
void QwtAbstractSlider::sliderMoved (doublevalue) [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
void QwtDial::updateMask () [protected, virtual, inherited]
Update the mask of the dial. In case of 'hasVisibleBackground() == false', the backgound is transparent by a mask.
See also:
- showBackground(), hasVisibleBackground()
void QwtDial::updateScale () [protected, inherited]Update the scale with the current attributes
See also:
- setScale()
double QwtDoubleRange::value () const [inherited]
Returns the current value.
Reimplemented in QwtCounter.
void QwtDial::valueChange () [protected, virtual, inherited]
QwtDoubleRange update hook.
Reimplemented from QwtAbstractSlider.
void QwtAbstractSlider::valueChanged (doublevalue) [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
bool QwtDial::wrapping () const [inherited]wrapping() holds whether it is possible to step the value from the highest value to the lowest value and vice versa.
See also:
- setWrapping(), QwtDoubleRange::setPeriodic()
Note:
- The meaning of wrapping is like the wrapping property of QSpinBox, but not like it is used in QDial.
Author
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