The Wheel Widget. More...

#include <qwt_wheel.h>

Inheritance diagram for QwtWheel:

Classes
class	PrivateData

Public Slots
void	setValue (double)
	Set a new value without adjusting to the step raster.

void	setTotalAngle (double)
	Set the total angle which the wheel can be turned.

void	setViewAngle (double)
	Specify the visible portion of the wheel.

void	setMass (double)
	Set the slider's mass for flywheel effect.

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

void	wheelPressed ()
	Signal emitted when the user presses the wheel with the mouse.

void	wheelReleased ()
	Signal emitted when the user releases the mouse.

void	wheelMoved (double value)
	Signal emitted when the user moves the wheel with the mouse.

Public Member Functions
	QwtWheel (QWidget *parent=nullptr)
	Constructor.

	~QwtWheel () override
	Destructor.

double	value () const
	Return the current value.

void	setOrientation (Qt::Orientation)
	Set the wheel orientation.

Qt::Orientation	orientation () const
	Return the orientation.

double	totalAngle () const
	Return the total angle.

double	viewAngle () const
	Return the view angle.

void	setTickCount (int)
	Set the number of ticks.

int	tickCount () const
	Return the number of ticks.

void	setWheelWidth (int)
	Set the wheel width.

int	wheelWidth () const
	Return the wheel width.

void	setWheelBorderWidth (int)
	Set the wheel border width.

int	wheelBorderWidth () const
	Return the wheel border width.

void	setBorderWidth (int)
	Set the outer border width.

int	borderWidth () const
	Return the outer border width.

void	setFlatStyle (bool)
	Set flat style.

bool	flatStyle () const
	Return flat style.

void	setInverted (bool)
	Set inverted appearance.

bool	isInverted () const
	Return whether the wheel is inverted.

void	setWrapping (bool)
	Set wrapping mode.

bool	wrapping () const
	Return whether wrapping is enabled.

void	setSingleStep (double)
	Set single step size.

double	singleStep () const
	Return single step size.

void	setPageStepCount (int)
	Set page step count.

int	pageStepCount () const
	Return page step count.

void	setStepAlignment (bool on)
	Set step alignment.

bool	stepAlignment () const
	Return whether step alignment is enabled.

void	setRange (double min, double max)
	Set value range.

void	setMinimum (double)
	Set minimum value.

double	minimum () const
	Return minimum value.

void	setMaximum (double)
	Set maximum value.

double	maximum () const
	Return maximum value.

void	setUpdateInterval (int)
	Set update interval.

int	updateInterval () const
	Return update interval.

void	setTracking (bool)
	Set tracking mode.

bool	isTracking () const
	Return whether tracking is enabled.

double	mass () const
	Return mass for flywheel effect.

Protected Member Functions
virtual void	paintEvent (QPaintEvent *) override
	Qt Paint Event.

virtual void	mousePressEvent (QMouseEvent *) override
	Mouse press event handler.

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

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

virtual void	keyPressEvent (QKeyEvent *) override
	Handle key events.

virtual void	wheelEvent (QWheelEvent *) override
	Handle wheel events.

virtual void	timerEvent (QTimerEvent *) override
	Qt timer event.

void	stopFlying ()
	Stop the flying movement of the wheel.

QRect	wheelRect () const

virtual QSize	sizeHint () const override
	Return the size hint.

virtual QSize	minimumSizeHint () const override
	Return the minimum size hint.

virtual void	drawTicks (QPainter *, const QRectF &)
	Draw the Wheel's ticks.

virtual void	drawWheelBackground (QPainter *, const QRectF &)
	Draw the Wheel's background gradient.

virtual double	valueAt (const QPoint &) const
	Determine the value corresponding to a specified point.

Properties
Qt::Orientation	orientation

double	value

double	minimum

double	maximum

double	singleStep

int	pageStepCount

bool	stepAlignment

bool	tracking

bool	wrapping

bool	inverted

double	mass

int	updateInterval

double	totalAngle

double	viewAngle

int	tickCount

int	wheelWidth

int	borderWidth

int	wheelBorderWidth

bool	flatStyle

Detailed Description

The Wheel Widget.

The wheel widget can be used to change values over a very large range in very small steps. Using the setMass() member, it can be configured as a flying wheel. The default range of the wheel is [0.0, 100.0]

See also: The radio example.

Member Function Documentation

◆ borderWidth()

int QwtWheel::borderWidth ( ) const

Return the outer border width.

Returns: Border width

See also: setBorderWidth()

◆ drawTicks()

void QwtWheel::drawTicks	(	QPainter *	painter,
		const QRectF &	rect
	)

protectedvirtual

Draw the Wheel's ticks.

Parameters

painter	Painter
rect	Geometry for the wheel

◆ drawWheelBackground()

void QwtWheel::drawWheelBackground	(	QPainter *	painter,
		const QRectF &	rect
	)

protectedvirtual

Draw the Wheel's background gradient.

Parameters

painter	Painter
rect	Geometry for the wheel

◆ flatStyle()

bool QwtWheel::flatStyle ( ) const

Return flat style.

Return whether flat style is enabled.

See also: setFlatStyle()

◆ isInverted()

bool QwtWheel::isInverted ( ) const

Return whether the wheel is inverted.

Returns: True when the wheel is inverted

See also: setInverted()

◆ isTracking()

bool QwtWheel::isTracking ( ) const

Return whether tracking is enabled.

Returns: True, when tracking is enabled

See also: setTracking(), valueChanged(), wheelMoved()

◆ keyPressEvent()

void QwtWheel::keyPressEvent ( QKeyEvent * event )

overrideprotectedvirtual

Handle key events.

Qt::Key_Home
Step to minimum()
Qt::Key_End
Step to maximum()
Qt::Key_Up
In case of a horizontal or not inverted vertical wheel the value will be incremented by the step size. For an inverted vertical wheel the value will be decremented by the step size.
Qt::Key_Down
In case of a horizontal or not inverted vertical wheel the value will be decremented by the step size. For an inverted vertical wheel the value will be incremented by the step size.
Qt::Key_PageUp
The value will be incremented by pageStepSize() * singleStepSize().
Qt::Key_PageDown
The value will be decremented by pageStepSize() * singleStepSize().

Parameters

event Key event

◆ mass()

double QwtWheel::mass ( ) const

Return mass for flywheel effect.

Return the mass for flywheel effect.

Returns: Mass in kg

See also: setMass()

◆ maximum()

double QwtWheel::maximum ( ) const

Return maximum value.

Return the maximum of the range.

Returns: Maximum value

See also: setRange(), setMaximum(), minimum()

◆ minimum()

double QwtWheel::minimum ( ) const

Return minimum value.

Return the minimum of the range.

Returns: Minimum value

See also: setRange(), setMinimum(), maximum()

◆ minimumSizeHint()

QSize QwtWheel::minimumSizeHint ( ) const

overrideprotectedvirtual

Return the minimum size hint.

Returns: Minimum size hint

Warning: The return value is based on the wheel width.

◆ mouseMoveEvent()

void QwtWheel::mouseMoveEvent ( QMouseEvent * event )

overrideprotectedvirtual

Mouse Move Event handler.

Turn the wheel according to the mouse position

Parameters

event Mouse event

◆ mousePressEvent()

void QwtWheel::mousePressEvent ( QMouseEvent * event )

overrideprotectedvirtual

Mouse press event handler.

Start movement of the wheel.

Parameters

event Mouse event

◆ mouseReleaseEvent()

void QwtWheel::mouseReleaseEvent ( QMouseEvent * event )

overrideprotectedvirtual

Mouse Release Event handler.

When the wheel has no mass the movement of the wheel stops, otherwise it starts flying.

Parameters

event Mouse event

◆ orientation()

Qt::Orientation QwtWheel::orientation ( ) const

Return the orientation.

Returns: Orientation

See also: setOrientation()

◆ pageStepCount()

int QwtWheel::pageStepCount ( ) const

Return page step count.

Return the page step count.

Returns: Page step count

See also: setPageStepCount(), singleStep()

◆ paintEvent()

void QwtWheel::paintEvent ( QPaintEvent * event )

overrideprotectedvirtual

Qt Paint Event.

Parameters

event Paint event

◆ setBorderWidth()

void QwtWheel::setBorderWidth ( int width )

Set the outer border width.

Set the border width.

The border defaults to 2.

Parameters

width Border width

See also: borderWidth()

◆ setFlatStyle()

void QwtWheel::setFlatStyle ( bool on )

Set flat style.

When enabled (default), the wheel is drawn with flat colors instead of 3D embossed effects.

Parameters

on	true for flat style, false for classic 3D style

See also: flatStyle()

◆ setInverted()

void QwtWheel::setInverted ( bool on )

Set inverted appearance.

En/Disable inverted appearance.

An inverted wheel increases its values in the opposite direction. The direction of an inverted horizontal wheel will be from right to left, an inverted vertical wheel will increase from bottom to top.

Parameters

[in] on En/Disable inverted appearance

See also: isInverted()

◆ setMass

void QwtWheel::setMass ( double mass )

slot

Set the slider's mass for flywheel effect.

If the slider's mass is greater than 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

[in] mass New mass in kg

Warning: If the mass is smaller than 1g, it is set to zero. The maximal mass is limited to 100kg.

See also: mass()

◆ setMaximum()

void QwtWheel::setMaximum ( double value )

Set maximum value.

Set the maximum value of the range.

Parameters

[in] value Maximum value

See also: setRange(), setMinimum(), maximum()

◆ setMinimum()

void QwtWheel::setMinimum ( double value )

Set minimum value.

Set the minimum value of the range.

Parameters

[in] value Minimum value

See also: setRange(), setMaximum(), minimum()

Note: The maximum is adjusted if necessary to ensure that the range remains valid.

◆ setOrientation()

void QwtWheel::setOrientation ( Qt::Orientation orientation )

Set the wheel orientation.

Set the wheel's orientation.

The default orientation is Qt::Horizontal.

Parameters

[in] orientation Qt::Horizontal or Qt::Vertical

See also: orientation()

◆ setPageStepCount()

void QwtWheel::setPageStepCount ( int count )

Set page step count.

Set the page step count.

pageStepCount is a multiplicator for the single step size that typically corresponds to the user pressing PageUp or PageDown. A value of 0 disables page stepping. The default value is 1.

Parameters

[in] count Multiplicator for the single step size

See also: pageStepCount(), setSingleStep()

◆ setRange()

void QwtWheel::setRange	(	double	min,
		double	max
	)

Set value range.

Set the minimum and maximum values.

The maximum is adjusted if necessary to ensure that the range remains valid. The value might be modified to be inside of the range.

Parameters

[in]	min	Minimum value
[in]	max	Maximum value

See also: minimum(), maximum()

◆ setSingleStep()

void QwtWheel::setSingleStep ( double stepSize )

Set single step size.

Set the step size of the counter.

A value <= 0.0 disables stepping.

Parameters

[in] stepSize Single step size

See also: singleStep(), setPageStepCount()

◆ setStepAlignment()

void QwtWheel::setStepAlignment ( bool on )

Set step alignment.

En/Disable step alignment.

When step alignment is enabled, value changes initiated by user input (mouse, keyboard, wheel) are aligned to multiples of the single step.

Parameters

[in] on On/Off

See also: stepAlignment(), setSingleStep()

◆ setTickCount()

void QwtWheel::setTickCount ( int count )

Set the number of ticks.

Adjust the number of grooves in the wheel's surface.

The number of grooves is limited to 6 <= count <= 50. Values outside this range will be clipped. The default value is 10.

Parameters

count Number of grooves per 360 degrees

See also: tickCount()

◆ setTotalAngle

void QwtWheel::setTotalAngle ( double angle )

slot

Set the total angle which the wheel can be turned.

One full turn of the wheel corresponds to an angle of 360 degrees. A total angle of n*360 degrees means that the wheel has to be turned n times around its axis to get from the minimum value to the maximum value.

The default setting of the total angle is 360 degrees.

Parameters

angle total angle in degrees

See also: totalAngle()

◆ setTracking()

void QwtWheel::setTracking ( bool enable )

Set tracking mode.

En/Disable tracking.

If tracking is enabled (the default), the wheel emits the valueChanged() signal while the wheel is moving. If tracking is disabled, the wheel emits the valueChanged() signal only when the wheel movement is terminated.

The wheelMoved() signal is emitted regardless id tracking is enabled or not.

Parameters

enable On/Off

See also: isTracking()

◆ setUpdateInterval()

void QwtWheel::setUpdateInterval ( int interval )

Set update interval.

Specify the update interval when the wheel is flying.

Default and minimum value is 50 ms.

Parameters

interval Interval in milliseconds

See also: updateInterval(), setMass(), setTracking()

◆ setValue

void QwtWheel::setValue ( double value )

slot

Set a new value without adjusting to the step raster.

Parameters

[in] value New value

See also: value(), valueChanged()

Warning: The value is clipped when it lies outside the range.

◆ setViewAngle

void QwtWheel::setViewAngle ( double angle )

slot

Specify the visible portion of the wheel.

You may use this function for fine-tuning the appearance of the wheel. The default value is 175 degrees. The value is limited from 10 to 175 degrees.

Parameters

[in] angle Visible angle in degrees

See also: viewAngle(), setTotalAngle()

◆ setWheelBorderWidth()

void QwtWheel::setWheelBorderWidth ( int borderWidth )

Set the wheel border width.

Set the wheel border width of the wheel.

The wheel border must not be smaller than 1 and is limited in dependence on the wheel's size. Values outside the allowed range will be clipped.

The wheel border defaults to 2.

Parameters

borderWidth Border width

See also: internalBorder()

◆ setWheelWidth()

void QwtWheel::setWheelWidth ( int width )

Set the wheel width.

Set the width of the wheel.

Corresponds to the wheel height for horizontal orientation, and the wheel width for vertical orientation.

Parameters

[in] width The wheel's width

See also: wheelWidth()

◆ setWrapping()

void QwtWheel::setWrapping ( bool on )

Set wrapping mode.

En/Disable wrapping.

If wrapping is true, stepping up from maximum() value will take you to the minimum() value and vice versa.

Parameters

[in] on En/Disable wrapping

See also: wrapping()

◆ singleStep()

double QwtWheel::singleStep ( ) const

Return single step size.

Return the single step size.

Returns: Single step size

See also: setSingleStep()

◆ sizeHint()

QSize QwtWheel::sizeHint ( ) const

overrideprotectedvirtual

Return the size hint.

Returns: Size hint

◆ stepAlignment()

bool QwtWheel::stepAlignment ( ) const

Return whether step alignment is enabled.

Returns: True when step alignment is enabled

See also: setStepAlignment(), singleStep()

◆ tickCount()

int QwtWheel::tickCount ( ) const

Return the number of ticks.

Returns: Number of grooves in the wheel's surface.

See also: setTickCnt()

◆ timerEvent()

void QwtWheel::timerEvent ( QTimerEvent * event )

overrideprotectedvirtual

Qt timer event.

The flying wheel effect is implemented using a timer

Parameters

event Timer event

See also: updateInterval()

◆ totalAngle()

double QwtWheel::totalAngle ( ) const

Return the total angle.

Returns: Total angle which the wheel can be turned.

See also: setTotalAngle()

◆ updateInterval()

int QwtWheel::updateInterval ( ) const

Return update interval.

Returns: Update interval when the wheel is flying

See also: setUpdateInterval(), mass(), isTracking()

◆ value()

double QwtWheel::value ( ) const

Return the current value.

Return the current value of the wheel.

Returns: Current value

See also: setValue(), valueChanged()

◆ valueAt()

double QwtWheel::valueAt ( const QPoint & pos ) const

protectedvirtual

Determine the value corresponding to a specified point.

Parameters

pos Position

Returns: Value corresponding to pos

◆ valueChanged

void QwtWheel::valueChanged ( double value )

signal

Notify a change of value.

When tracking is enabled this signal will be emitted every time the value changes.

Parameters

[in] value New value

See also: setTracking()

◆ viewAngle()

double QwtWheel::viewAngle ( ) const

Return the view angle.

Return the visible portion of the wheel.

Returns: Visible angle in degrees

See also: setViewAngle(), totalAngle()

◆ wheelBorderWidth()

int QwtWheel::wheelBorderWidth ( ) const

Return the wheel border width.

Returns: Wheel border width

See also: setWheelBorderWidth()

◆ wheelEvent()

void QwtWheel::wheelEvent ( QWheelEvent * event )

overrideprotectedvirtual

Handle wheel events.

In/Decrement the value

Parameters

event Wheel event

◆ wheelMoved

void QwtWheel::wheelMoved ( double value )

signal

Signal emitted when the user moves the wheel with the mouse.

Parameters

[in] value New value

◆ wheelRect()

QRect QwtWheel::wheelRect ( ) const

protected

Returns: Rectangle of the wheel without the outer border

◆ wheelWidth()

int QwtWheel::wheelWidth ( ) const

Return the wheel width.

Return the width of the wheel.

Returns: Wheel width

See also: setWheelWidth()

◆ wrapping()

bool QwtWheel::wrapping ( ) const

Return whether wrapping is enabled.

Returns: True when wrapping is set

See also: setWrapping()

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

/home/runner/work/QWT/QWT/src/plot/qwt_wheel.h
/home/runner/work/QWT/QWT/src/plot/qwt_wheel.cpp

Classes

Public Slots

Signals

Public Member Functions

Protected Member Functions

Properties

Detailed Description

Member Function Documentation

◆ borderWidth()

◆ drawTicks()

◆ drawWheelBackground()

◆ flatStyle()

◆ isInverted()

◆ isTracking()

◆ keyPressEvent()

◆ mass()

◆ maximum()

◆ minimum()

◆ minimumSizeHint()

◆ mouseMoveEvent()

◆ mousePressEvent()

◆ mouseReleaseEvent()

◆ orientation()

◆ pageStepCount()

◆ paintEvent()

◆ setBorderWidth()

◆ setFlatStyle()

◆ setInverted()

◆ setMass

◆ setMaximum()

◆ setMinimum()

◆ setOrientation()

◆ setPageStepCount()

◆ setRange()

◆ setSingleStep()

◆ setStepAlignment()

◆ setTickCount()

◆ setTotalAngle

◆ setTracking()

◆ setUpdateInterval()

◆ setValue

◆ setViewAngle

◆ setWheelBorderWidth()

◆ setWheelWidth()

◆ setWrapping()

◆ singleStep()

◆ sizeHint()

◆ stepAlignment()

◆ tickCount()

◆ timerEvent()

◆ totalAngle()

◆ updateInterval()

◆ value()

◆ valueAt()

◆ valueChanged

◆ viewAngle()

◆ wheelBorderWidth()

◆ wheelEvent()

◆ wheelMoved

◆ wheelRect()

◆ wheelWidth()

◆ wrapping()