QwtAbstractSlider Class Reference

Inheritance diagram for QwtAbstractSlider:

[legend]Collaboration diagram for QwtAbstractSlider:

[legend]List of all members.

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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.

Definition at line 28 of file qwt_abstract_slider.h.

Public Types
enum	ScrollMode {   ScrNone,   ScrMouse,   ScrTimer,   ScrDirect,   ScrPage }
Public Slots
virtual void	setValue (double val)
virtual void	fitValue (double val)
virtual void	incValue (int steps)
virtual void	setReadOnly (bool)
Signals
void	valueChanged (double value)
void	sliderPressed ()
void	sliderReleased ()
void	sliderMoved (double value)
Public Member Functions
	QwtAbstractSlider (Qt::Orientation, QWidget *parent=NULL)
virtual	~QwtAbstractSlider ()
void	setUpdateTime (int t)
void	stopMoving ()
void	setTracking (bool enable)
virtual void	setMass (double val)
virtual double	mass () const
virtual void	setOrientation (Qt::Orientation o)
Qt::Orientation	orientation () const
bool	isReadOnly () const
bool	isValid () const
void	setValid (bool valid)
Protected Member Functions
virtual void	setPosition (const QPoint &)
virtual void	valueChange ()
virtual void	timerEvent (QTimerEvent *e)
virtual void	mousePressEvent (QMouseEvent *e)
virtual void	mouseReleaseEvent (QMouseEvent *e)
virtual void	mouseMoveEvent (QMouseEvent *e)
virtual void	keyPressEvent (QKeyEvent *e)
virtual void	wheelEvent (QWheelEvent *e)
virtual double	getValue (const QPoint &p)=0
virtual void	getScrollMode (const QPoint &p, int &scrollMode, int &direction)=0
void	setMouseOffset (double)
double	mouseOffset () const
int	scrollMode () const

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Member Enumeration Documentation

enum QwtAbstractSlider::ScrollMode

Scroll mode See also: getScrollMode() Definition at line 50 of file qwt_abstract_slider.h.

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Constructor & Destructor Documentation

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

Constructor. Parameters: orientation  Orientation parent  Parent widget Definition at line 54 of file qwt_abstract_slider.cpp.

QwtAbstractSlider::~QwtAbstractSlider (   )  [virtual]

Destructor. Definition at line 68 of file qwt_abstract_slider.cpp.

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Member Function Documentation

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

Set the slider's value to the nearest integer multiple of the step size. Parameters: valeu  Value See also: setValue(), incValue() Reimplemented from QwtDoubleRange. Definition at line 550 of file qwt_abstract_slider.cpp. References QwtDoubleRange::fitValue(), and stopMoving().

virtual void QwtAbstractSlider::getScrollMode (  const QPoint &  p, int &  scrollMode, int &  direction )  [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. QwtAbstractSlider knows the following modes: QwtAbstractSlider::ScrNone Scrolling switched off. Don't change the value. QwtAbstractSlider::ScrMouse Change the value while the user keeps the button pressed and moves the mouse. QwtAbstractSlider::ScrTimer Automatic scrolling. Increment the value in the specified direction as long as the user keeps the button pressed. QwtAbstractSlider::ScrPage Automatic scrolling. Same as ScrTimer, but increment by page size. Parameters: p  point where the mouse was pressed Return values: scrollMode  The scrolling mode direction  direction: 1, 0, or -1. Implemented in QwtDial, QwtSlider, and QwtWheel. Referenced by mousePressEvent(), and wheelEvent().

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, QwtSlider, and QwtWheel. Referenced by mousePressEvent(), and setPosition().

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. Definition at line 562 of file qwt_abstract_slider.cpp. References QwtDoubleRange::incValue(), and stopMoving().

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() Definition at line 98 of file qwt_abstract_slider.cpp. Referenced by QwtDial::drawFocusIndicator(), QwtDial::keyPressEvent(), QwtCompass::keyPressEvent(), keyPressEvent(), mouseMoveEvent(), mousePressEvent(), mouseReleaseEvent(), and wheelEvent().

bool QwtAbstractSlider::isValid (   )  const [inline]

See also: QwtDblRange::isValid Reimplemented from QwtDoubleRange. Definition at line 87 of file qwt_abstract_slider.h. References QwtDoubleRange::isValid(). Referenced by QwtDial::drawContents(), QwtKnob::drawKnob(), QwtAnalogClock::drawNeedle(), QwtCompass::drawScaleContents(), QwtSlider::drawSlider(), QwtDial::keyPressEvent(), keyPressEvent(), mouseMoveEvent(), mousePressEvent(), mouseReleaseEvent(), and wheelEvent().

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 QwtCompass, and QwtDial. Definition at line 371 of file qwt_abstract_slider.cpp. References isReadOnly(), isValid(), and orientation().

double QwtAbstractSlider::mass (   )  const [virtual]

Returns: mass See also: setMass() Reimplemented in QwtWheel. Definition at line 521 of file qwt_abstract_slider.cpp. Referenced by QwtWheel::mass().

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

Mouse Move Event handler Parameters: e  Mouse event Definition at line 305 of file qwt_abstract_slider.cpp. References QwtDoubleRange::exactPrevValue(), QwtDoubleRange::exactValue(), isReadOnly(), isValid(), QwtDoubleRange::prevValue(), setPosition(), sliderMoved(), and QwtDoubleRange::value().

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

Mouse press event handler. Definition at line 147 of file qwt_abstract_slider.cpp. References getScrollMode(), getValue(), isReadOnly(), isValid(), sliderPressed(), stopMoving(), and QwtDoubleRange::value().

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

Mouse Release Event handler. Definition at line 196 of file qwt_abstract_slider.cpp. References QwtDoubleRange::fitValue(), QwtDoubleRange::incPages(), isReadOnly(), isValid(), setPosition(), sliderReleased(), QwtDoubleRange::step(), stopMoving(), and QwtDoubleRange::value().

Qt::Orientation QwtAbstractSlider::orientation (   )  const

Returns: Orientation See also: setOrientation() Definition at line 117 of file qwt_abstract_slider.cpp. Referenced by QwtSlider::drawSlider(), QwtSlider::drawThumb(), QwtWheel::drawWheel(), QwtWheel::drawWheelBackground(), QwtWheel::getValue(), QwtSlider::getValue(), keyPressEvent(), QwtSlider::layoutSlider(), QwtWheel::minimumSizeHint(), QwtSlider::minimumSizeHint(), QwtWheel::setOrientation(), and QwtSlider::setOrientation().

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. Definition at line 507 of file qwt_abstract_slider.cpp. Referenced by QwtWheel::setMass().

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. Definition at line 108 of file qwt_abstract_slider.cpp. Referenced by QwtWheel::setOrientation(), and QwtSlider::setOrientation().

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

Move the slider to a specified point, adjust the value and emit signals if necessary. Definition at line 276 of file qwt_abstract_slider.cpp. References QwtDoubleRange::fitValue(), and getValue(). Referenced by mouseMoveEvent(), and mouseReleaseEvent().

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() Definition at line 85 of file qwt_abstract_slider.cpp.

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. Definition at line 296 of file qwt_abstract_slider.cpp.

void QwtAbstractSlider::setUpdateTime (  int  t  )

Specify the update interval for automatic scrolling. Parameters: t  update interval in milliseconds See also: getScrollMode() Definition at line 138 of file qwt_abstract_slider.cpp.

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

See also: QwtDblRange::isValid Reimplemented from QwtDoubleRange. Definition at line 92 of file qwt_abstract_slider.h. References QwtDoubleRange::setValid().

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. Definition at line 535 of file qwt_abstract_slider.cpp. References QwtDoubleRange::setValue(), and stopMoving(). Referenced by QwtDial::keyPressEvent(), and QwtAnalogClock::setTime().

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

This signal is emitted when the user moves the slider with the mouse. Parameters: value  new value Referenced by mouseMoveEvent(), and wheelEvent().

void QwtAbstractSlider::sliderPressed (   )  [signal]

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

void QwtAbstractSlider::sliderReleased (   )  [signal]

This signal is emitted when the user releases the movable part of the slider. Referenced by mouseReleaseEvent().

void QwtAbstractSlider::stopMoving (   )

Stop updating if automatic scrolling is active. Definition at line 124 of file qwt_abstract_slider.cpp. Referenced by fitValue(), incValue(), mousePressEvent(), mouseReleaseEvent(), setValue(), and timerEvent().

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

Qt timer event Parameters: e  Timer event Definition at line 417 of file qwt_abstract_slider.cpp. References QwtDoubleRange::exactValue(), QwtDoubleRange::fitValue(), QwtDoubleRange::incPages(), QwtDoubleRange::step(), stopMoving(), and QwtDoubleRange::value().

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. Definition at line 484 of file qwt_abstract_slider.cpp. References QwtDoubleRange::value(), and valueChanged(). Referenced by QwtWheel::valueChange(), QwtSlider::valueChange(), and QwtDial::valueChange().

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 Referenced by valueChange().

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

Wheel Event handler Parameters: e  Whell event Definition at line 336 of file qwt_abstract_slider.cpp. References getScrollMode(), QwtDoubleRange::incPages(), isReadOnly(), isValid(), QwtDoubleRange::prevValue(), sliderMoved(), and QwtDoubleRange::value().

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