NAME
QwtPlotScaleItem - A class which draws a scale inside the plot canvas.
SYNOPSIS
#include <qwt_plot_scaleitem.h>
Inherits QwtPlotItem.
Public Member Functions
QwtPlotScaleItem (QwtScaleDraw::Alignment=QwtScaleDraw::BottomScale,
const double pos=0.0)
virtual ~QwtPlotScaleItem ()
virtual int rtti () const
void setScaleDiv (const QwtScaleDiv &)
const QwtScaleDiv & scaleDiv () const
void setScaleDivFromAxis (bool on)
bool isScaleDivFromAxis () const
void setPalette (const QPalette &)
QPalette palette () const
void setFont (const QFont &)
QFont font () const
void setScaleDraw (QwtScaleDraw *)
const QwtScaleDraw * scaleDraw () const
QwtScaleDraw * scaleDraw ()
void setPosition (double pos)
double position () const
void setBorderDistance (int numPixels)
int borderDistance () const
void setAlignment (QwtScaleDraw::Alignment)
virtual void draw (QPainter *p, const QwtScaleMap &xMap, const
QwtScaleMap &yMap, const QRect &rect) const
virtual void updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &)
Detailed Description
A class which draws a scale inside the plot canvas.
QwtPlotScaleItem can be used to draw an axis inside the plot canvas. It
might by synchronized to one of the axis of the plot, but can also
display its own ticks and labels.
It is allowed to synchronize the scale item with a disabled axis. In
plots with vertical and horizontal scale items, it might be necessary
to remove ticks at the intersections, by overloading updateScaleDiv().
The scale might be at a specific position (f.e 0.0) or it might be
aligned to a canvas border.
Example.RS 4 The following example shows how to replace the left axis,
by a scale item at the x position 0.0.
QwtPlotScaleItem *scaleItem =
new QwtPlotScaleItem(QwtScaleDraw::RightScale, 0.0);
scaleItem->setFont(plot->axisWidget(QwtPlot::yLeft)->font());
scaleItem->attach(plot);
plot->enableAxis(QwtPlot::yLeft, false);
Constructor & Destructor Documentation
QwtPlotScaleItem::QwtPlotScaleItem (QwtScaleDraw::Alignment alignment =
QwtScaleDraw::BottomScale, const double pos = 0.0) [explicit]
Constructor for scale item at the position pos.
Parameters:
alignment In case of QwtScaleDraw::BottomScale/QwtScaleDrawTopScale
the scale item is corresponding to the xAxis(), otherwise it
corresponds to the yAxis().
pos x or y position, depending on the corresponding axis.
See also:
setPosition(), setAlignment()
QwtPlotScaleItem::~QwtPlotScaleItem () [virtual]
Destructor.
Member Function Documentation
int QwtPlotScaleItem::borderDistance () const
Returns:
Distance from a canvas border
See also:
setBorderDistance(), setPosition()
void QwtPlotScaleItem::draw (QPainter * p, const QwtScaleMap & xMap, const
QwtScaleMap & yMap, const QRect & rect) const [virtual]
Draw the scale.
Implements QwtPlotItem.
QFont QwtPlotScaleItem::font () const
Returns:
tick label font
See also:
setFont()
bool QwtPlotScaleItem::isScaleDivFromAxis () const
Returns:
True, if the synchronization of the scale division with the
corresponding axis is enabled.
See also:
setScaleDiv(), setScaleDivFromAxis()
QPalette QwtPlotScaleItem::palette () const
Returns:
palette
See also:
setPalette()
double QwtPlotScaleItem::position () const
Returns:
Position of the scale
See also:
setPosition(), setAlignment()
int QwtPlotScaleItem::rtti () const [virtual]
Returns:
QwtPlotItem::Rtti_PlotScale
Reimplemented from QwtPlotItem.
const QwtScaleDiv & QwtPlotScaleItem::scaleDiv () const
Returns:
Scale division
QwtScaleDraw * QwtPlotScaleItem::scaleDraw ()
Returns:
Scale draw
See also:
setScaleDraw()
const QwtScaleDraw * QwtPlotScaleItem::scaleDraw () const
Returns:
Scale draw
See also:
setScaleDraw()
void QwtPlotScaleItem::setAlignment (QwtScaleDraw::Alignment alignment)
Change the alignment of the scale
The alignment sets the orientation of the scale and the position of the
ticks:
· QwtScaleDraw::BottomScale: horizontal, ticks below
· QwtScaleDraw::TopScale: horizontal, ticks above
· QwtScaleDraw::LeftScale: vertical, ticks left
· QwtScaleDraw::RightScale: vertical, ticks right
For horizontal scales the position corresponds to QwtPlotItem::yAxis(),
otherwise to QwtPlotItem::xAxis().
See also:
scaleDraw(), QwtScaleDraw::alignment(), setPosition()
void QwtPlotScaleItem::setBorderDistance (int distance)
Align the scale to the canvas.
If distance is >= 0 the scale will be aligned to a border of the
contents rect of the canvas. If alignment() is QwtScaleDraw::LeftScale,
the scale will be aligned to the right border, if it is
QwtScaleDraw::TopScale it will be aligned to the bottom (and vice
versa),
If distance is < 0 the scale will be at the position().
Parameters:
distance Number of pixels between the canvas border and the
backbone of the scale.
See also:
setPosition(), borderDistance()
void QwtPlotScaleItem::setFont (const QFont & font)
Change the tick label font
See also:
font()
void QwtPlotScaleItem::setPalette (const QPalette & palette)
Set the palette
See also:
QwtAbstractScaleDraw::draw(), palette()
void QwtPlotScaleItem::setPosition (double pos)
Change the position of the scale
The position is interpreted as y value for horizontal axes and as x
value for vertical axes.
The border distance is set to -1.
Parameters:
pos New position
See also:
position(), setAlignment()
void QwtPlotScaleItem::setScaleDiv (const QwtScaleDiv & scaleDiv)
Assign a scale division.
When assigning a scaleDiv the scale division won’t be synchronized with
the corresponding axis anymore.
Parameters:
scaleDiv Scale division
See also:
scaleDiv(), setScaleDivFromAxis(), isScaleDivFromAxis()
void QwtPlotScaleItem::setScaleDivFromAxis (bool on)
Enable/Disable the synchronization of the scale division with the
corresponding axis.
Parameters:
on true/false
See also:
isScaleDivFromAxis()
void QwtPlotScaleItem::setScaleDraw (QwtScaleDraw * scaleDraw)
Set a scale draw.
Parameters:
scaleDraw object responsible for drawing scales.
The main use case for replacing the default QwtScaleDraw is to overload
QwtAbstractScaleDraw::label, to replace or swallow tick labels.
See also:
scaleDraw()
void QwtPlotScaleItem::updateScaleDiv (const QwtScaleDiv & xScaleDiv, const
QwtScaleDiv & yScaleDiv) [virtual]
Update the item to changes of the axes scale division.
In case of isScaleDivFromAxis(), the scale draw is synchronized to the
correspond axis.
Parameters:
xScaleDiv Scale division of the x-axis
yScaleDiv Scale division of the y-axis
See also:
QwtPlot::updateAxes()
Reimplemented from QwtPlotItem.
Author
Generated automatically by Doxygen for Qwt User’s Guide from the source
code.