trusty (3) QwtAbstractSlider.3.gz
NAME
QwtAbstractSlider -
An abstract base class for slider widgets.
SYNOPSIS
#include <qwt_abstract_slider.h>
Inherits QwtDoubleRange.
Inherited by QwtDial, QwtKnob, QwtSlider, and QwtWheel.
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 &pos, ScrollMode &scrollMode, int &direction) const =0
void setMouseOffset (double)
double mouseOffset () const
int scrollMode () const
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::Orientationorientation, QWidget *parent = NULL) [explicit]
Constructor. Parameters:
orientation Orientation
parent Parent widget
QwtAbstractSlider::~QwtAbstractSlider () [virtual]
Destructor.
Member Function Documentation
void QwtAbstractSlider::fitValue (doublevalue) [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 QwtAbstractSlider::incValue (intsteps) [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 QwtCompass, and QwtDial.
double QwtAbstractSlider::mass () const [virtual] Returns:
mass
See also:
setMass()
Reimplemented in QwtWheel.
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 QwtAbstractSlider::scrollMode () const [protected]
sa ScrollMode
void QwtAbstractSlider::setMass (doubleval) [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 (doubleoffset) [protected] See also:
mouseOffset()
void QwtAbstractSlider::setOrientation (Qt::Orientationo) [virtual]
Set the orientation. Parameters:
o Orientation. Allowed values are Qt::Horizontal and Qt::Vertical.
Reimplemented in QwtSlider, and QwtWheel.
void QwtAbstractSlider::setPosition (const QPoint &p) [protected, virtual] Move the slider to a specified
point, adjust the value and emit signals if necessary.
void QwtAbstractSlider::setReadOnly (boolreadOnly) [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 QwtAbstractSlider::setTracking (boolenable)
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)
Specify the update interval for automatic scrolling. Parameters:
t update interval in milliseconds
See also:
getScrollMode()
void QwtAbstractSlider::setValid (boolvalid) [inline] Parameters:
valid true/false
See also:
QwtDblRange::isValid()
Reimplemented from QwtDoubleRange.
void QwtAbstractSlider::setValue (doubleval) [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 (doublevalue) [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.
void QwtAbstractSlider::stopMoving ()
Stop updating if automatic scrolling is active.
void QwtAbstractSlider::timerEvent (QTimerEvent *e) [protected, virtual] Qt timer event
Parameters:
e Timer event
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 (doublevalue) [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
Author
Generated automatically by Doxygen for Qwt User's Guide from the source code.