Detailed Description
The QSlider widget provides a vertical or horizontal slider.
The slider is the classic widget for controlling a bounded value.
It lets the user move a slider along a horizontal or vertical
groove and translates the slider's position into an integer value
within the legal range.
QSlider inherits QRangeControl, which provides the "integer" side
of the slider. setRange() and value() are likely to be used by
practically all slider users; see the QRangeControl
documentation for information about the many other functions that
class provides.
The main functions offered by the slider itself are tickmark and
orientation control; you can use setTickmarks() to indicate where
you want the tickmarks to be, setTickInterval() to indicate how
many of them you want and setOrientation() to indicate whether the
slider is to be horizontal or vertical.
A slider has a default focusPolicy() of WeakWheelFocus, i.e. it
accepts focus on Tab and uses the mouse wheel and a suitable
keyboard interface.
See also QScrollBar, QSpinBox, GUI Design Handbook: Slider and Basic Widgets.
Member Type Documentation
QSlider::TickSetting
This enum specifies where the tickmarks are to be drawn relative
to the slider's groove and the handle the user moves.
- QSlider::NoMarks - do not draw any tickmarks.
- QSlider::Both - draw tickmarks on both sides of the groove.
- QSlider::Above - draw tickmarks above the (horizontal) slider
- QSlider::Below - draw tickmarks below the (horizontal) slider
- QSlider::Left - draw tickmarks to the left of the (vertical) slider
- QSlider::Right - draw tickmarks to the right of the (vertical) slider
Member Function Documentation
QSlider::QSlider ( QWidget * parent, const char * name = 0 )
Constructs a vertical slider.
The parent and name arguments are sent on to the QWidget
constructor.
QSlider::QSlider ( Orientation orientation, QWidget * parent, const char * name = 0 )
Constructs a slider.
The orientation must be Qt::Vertical or Qt::Horizontal.
The parent and name arguments are sent on to the QWidget
constructor.
QSlider::QSlider ( int minValue, int maxValue, int pageStep, int value, Orientation orientation, QWidget * parent, const char * name = 0 )
Constructs a slider whose value can never be smaller than minValue or greater than maxValue, whose page step size is pageStep and whose value is initially value (which is
guaranteed to be in range using bound()).
If orientation is Qt::Vertical the slider is vertical and if it
is Qt::Horizontal the slider is horizontal.
The parent and name arguments are sent on to the QWidget
constructor.
void QSlider::addStep () [slot]
Moves the slider one pageStep() up or right.
int QSlider::lineStep () const
Returns the current line step.
See the "lineStep" property for details.
int QSlider::maxValue () const
Returns the current maximum value of the slider.
See the "maxValue" property for details.
int QSlider::minValue () const
Returns the current minimum value of the slider.
See the "minValue" property for details.
Orientation QSlider::orientation () const
Returns the slider's orientation.
See the "orientation" property for details.
int QSlider::pageStep () const
Returns the current page step.
See the "pageStep" property for details.
void QSlider::rangeChange () [virtual protected]
Implements the virtual QRangeControl function.
Reimplemented from QRangeControl.
void QSlider::setLineStep ( int )
Sets the current line step.
See the "lineStep" property for details.
void QSlider::setMaxValue ( int )
Sets the current maximum value of the slider.
See the "maxValue" property for details.
void QSlider::setMinValue ( int )
Sets the current minimum value of the slider.
See the "minValue" property for details.
void QSlider::setOrientation ( Orientation ) [virtual]
Sets the slider's orientation.
See the "orientation" property for details.
void QSlider::setPageStep ( int )
Sets the current page step.
See the "pageStep" property for details.
void QSlider::setPalette ( const QPalette & p ) [virtual]
Reimplements the virtual function QWidget::setPalette().
Sets the background color to the mid color for Motif style sliders
using palette p.
Reimplemented from QWidget.
void QRangeControl::setRange ( int minValue, int maxValue )
Sets the range control's minimum value to minValue and its
maximum value to maxValue.
Calls the virtual rangeChange() function if one or both of the new
minimum and maximum values are different from the previous
setting. Calls the virtual valueChange() function if the current
value is adjusted because it was outside the new range.
If maxValue is smaller than minValue, minValue becomes
the only legal value.
See also minValue and maxValue.
Examples: listbox/listbox.cpp, t12/lcdrange.cpp, t5/main.cpp, t6/main.cpp, t8/lcdrange.cpp and xform/xform.cpp.
void QSlider::setTickInterval ( int ) [virtual]
Sets the interval between tickmarks.
See the "tickInterval" property for details.
void QSlider::setTickmarks ( TickSetting ) [virtual]
Sets the tickmark settings for this slider.
See the "tickmarks" property for details.
void QSlider::setTracking ( bool enable ) [virtual]
Sets whether slider tracking is enabled to enable.
See the "tracking" property for details.
void QSlider::setValue ( int ) [virtual slot]
Sets the current slider value.
See the "value" property for details.
void QSlider::sliderMoved ( int value ) [signal]
This signal is emitted when the slider is dragged, with the new
slider value as its argument.
void QSlider::sliderPressed () [signal]
This signal is emitted when the user presses the slider with the
mouse.
QRect QSlider::sliderRect () const
Returns the slider handle rectangle. (This is the visual marker
that the user can move.)
void QSlider::sliderReleased () [signal]
This signal is emitted when the user releases the slider with the mouse.
int QSlider::sliderStart () const
Returns the start position of the slider.
void QSlider::subtractStep () [slot]
Moves the slider one pageStep() down or left.
int QSlider::tickInterval () const
Returns the interval between tickmarks.
See the "tickInterval" property for details.
TickSetting QSlider::tickmarks () const
Returns the tickmark settings for this slider.
See the "tickmarks" property for details.
bool QSlider::tracking () const
Returns TRUE if slider tracking is enabled; otherwise returns FALSE.
See the "tracking" property for details.
int QSlider::value () const
Returns the current slider value.
See the "value" property for details.
void QSlider::valueChange () [virtual protected]
Implements the virtual QRangeControl function.
Reimplemented from QRangeControl.
void QSlider::valueChanged ( int value ) [signal]
This signal is emitted when the slider value is changed, with the
new slider value as its argument.
Examples: rangecontrols/rangecontrols.cpp, t12/lcdrange.cpp, t5/main.cpp, t6/main.cpp, t7/lcdrange.cpp and xform/xform.cpp.
Property Documentation
int lineStep
This property holds the current line step.
When setting lineStep, the virtual stepChange() function will be
called if the new line step is different from the previous
setting.
See also setSteps(), QRangeControl::pageStep() and setRange().
Set this property's value with setLineStep() and get this property's value with lineStep().
int maxValue
This property holds the current maximum value of the slider.
When setting this property, the QSlider::minValue is adjusted,
if necessary, to ensure that the range remains valid.
See also setRange().
Set this property's value with setMaxValue() and get this property's value with maxValue().
int minValue
This property holds the current minimum value of the slider.
When setting this property, the QSlider::maxValue is adjusted,
if necessary, to ensure that the range remains valid.
See also setRange().
Set this property's value with setMinValue() and get this property's value with minValue().
This property holds the slider's orientation.
The orientation must be Qt::Vertical (the default) or Qt::Horizontal.
Set this property's value with setOrientation() and get this property's value with orientation().
int pageStep
This property holds the current page step.
When setting pageStep, the virtual stepChange() function will be
called if the new page step is different from the previous
setting.
See also QRangeControl::setSteps(), lineStep and setRange().
Set this property's value with setPageStep() and get this property's value with pageStep().
int tickInterval
This property holds the interval between tickmarks.
This is a value interval, not a pixel interval. If it is 0, the
slider will choose between lineStep() and pageStep(). The initial
value of tickInterval is 0.
See also QRangeControl::lineStep() and QRangeControl::pageStep().
Set this property's value with setTickInterval() and get this property's value with tickInterval().
This property holds the tickmark settings for this slider.
The valid values are in QSlider::TickSetting. The default is
NoMarks.
See also tickInterval.
Set this property's value with setTickmarks() and get this property's value with tickmarks().
bool tracking
This property holds whether slider tracking is enabled.
If tracking is enabled (the default), the slider emits the
valueChanged() signal whenever the slider is being dragged. If
tracking is disabled, the slider emits the valueChanged() signal
when the user releases the mouse button (unless the value happens
to be the same as before).
Set this property's value with setTracking() and get this property's value with tracking().
int value
This property holds the current slider value.
Set this property's value with setValue() and get this property's value with value().
See also QRangeControl::value() and prevValue().
This file is part of the Qt toolkit.
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