#include <qwt_abstract_slider.h>

Inherited by QwtDial, QwtKnob, QwtSlider, and QwtWheel.

Public Types
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
virtual void	incPages (int)
bool	isReadOnly () const
bool	isValid () const
virtual double	mass () const
double	maxValue () const
double	minValue () const
Qt::Orientation	orientation () const
int	pageSize () const
bool	periodic () const
	QwtAbstractSlider (Qt::Orientation, QWidget *parent=NULL)
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	setStep (double)
void	setTracking (bool enable)
void	setUpdateTime (int t)
void	setValid (bool valid)
double	step () const
void	stopMoving ()
double	value () const
virtual	~QwtAbstractSlider ()
Protected Member Functions
double	exactPrevValue () const
double	exactValue () const
virtual void	getScrollMode (const QPoint &pos, ScrollMode &scrollMode, int &direction) const =0
virtual double	getValue (const QPoint &p)=0
virtual void	keyPressEvent (QKeyEvent *e)
virtual void	mouseMoveEvent (QMouseEvent *e)
double	mouseOffset () const
virtual void	mousePressEvent (QMouseEvent *e)
virtual void	mouseReleaseEvent (QMouseEvent *e)
double	prevValue () const
virtual void	rangeChange ()
int	scrollMode () const
void	setMouseOffset (double)
virtual void	setPosition (const QPoint &)
virtual void	stepChange ()
virtual void	timerEvent (QTimerEvent *e)
virtual void	valueChange ()
virtual void	wheelEvent (QWheelEvent *e)

Detailed Description

An abstract base class for slider widgets.

QwtAbstractSlider is a base class for slider widgets. It handles mouse events and updates the slider's value accordingly. Derived classes only have to implement the getValue() and getScrollMode() members, and should react to a valueChange(), which normally requires repainting.

Member Enumeration Documentation

enum QwtAbstractSlider::ScrollMode

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

QwtAbstractSlider::QwtAbstractSlider	(	Qt::Orientation	orientation,
		QWidget *	parent = `NULL`
	)		`[explicit]`

Constructor.

Parameters:

orientation	Orientation
parent	Parent widget

QwtAbstractSlider::~QwtAbstractSlider ( ) [virtual]

Destructor.

Member Function Documentation

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]

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

Parameters:

value Value

See also:: setValue(), incValue()

Reimplemented from QwtDoubleRange.

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

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

This function is abstract and has to be implemented by derived classes. It is called on a mousePress event. The derived class can determine what should happen next in dependence of the position where the mouse was pressed by returning scrolling mode and direction.

Parameters:

pos	point where the mouse was pressed

Return values:

scrollMode	The scrolling mode
direction	direction: 1, 0, or -1.

Implemented in QwtDial, QwtKnob, QwtSlider, and QwtWheel.

virtual double QwtAbstractSlider::getValue ( const QPoint & p ) [protected, pure virtual]

Determine the value corresponding to a specified poind.

This is an abstract virtual function which is called when the user presses or releases a mouse button or moves the mouse. It has to be implemented by the derived class.

Parameters:

p point

Implemented in QwtDial, QwtKnob, QwtSlider, and QwtWheel.

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]

Increment the value by a specified number of steps.

Parameters:

steps number of steps

See also:: setValue()

Reimplemented from QwtDoubleRange.

bool QwtAbstractSlider::isReadOnly ( ) const

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]

See also:: QwtDblRange::isValid()

Reimplemented from QwtDoubleRange.

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

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.

double QwtAbstractSlider::mass ( ) const [virtual]

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.

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]

Mouse Move Event handler

Parameters:

e	Mouse event

double QwtAbstractSlider::mouseOffset ( ) const [protected]

See also:: setMouseOffset()

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

Mouse press event handler

Parameters:

e	Mouse event

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

Mouse Release Event handler

Parameters:

e	Mouse event

Qt::Orientation QwtAbstractSlider::orientation ( ) const

Returns:: Orientation

See also:: setOrientation()

int QwtDoubleRange::pageSize ( ) const [inherited]

Returns the page size in steps.

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 QwtDoubleRange::rangeChange ( ) [protected, virtual, inherited]

Notify a change of the range.

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

Reimplemented in QwtDial, QwtCounter, and QwtSlider.

int QwtAbstractSlider::scrollMode ( ) const [protected]

sa ScrollMode

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

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]

See also:: mouseOffset()

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

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]

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]

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 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 QwtAbstractSlider::setTracking ( bool enable )

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 )

Specify the update interval for automatic scrolling.

Parameters:

t	update interval in milliseconds

See also:: getScrollMode()

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

Parameters:

valid true/false

See also:: QwtDblRange::isValid()

Reimplemented from QwtDoubleRange.

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

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 QwtAbstractSlider::sliderMoved ( double value ) [signal]

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

Parameters:

value new value

void QwtAbstractSlider::sliderPressed ( ) [signal]

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

void QwtAbstractSlider::sliderReleased ( ) [signal]

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 ( )

Stop updating if automatic scrolling is active.

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

Qt timer event

Parameters:

e	Timer event

double QwtDoubleRange::value ( ) const [inherited]

Returns the current value.

Reimplemented in QwtCounter.

void QwtAbstractSlider::valueChange ( ) [protected, virtual]

Notify change of value

This function can be reimplemented by derived classes in order to keep track of changes, i.e. repaint the widget. The default implementation emits a valueChanged() signal if tracking is enabled.

Reimplemented from QwtDoubleRange.

Reimplemented in QwtDial, QwtSlider, and QwtWheel.

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

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]

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