Base class for items on the plot canvas. More...
#include <qwt_plot_item.h>
Public Types | |
enum | RttiValues { Rtti_PlotItem = 0, Rtti_PlotGrid, Rtti_PlotScale, Rtti_PlotMarker, Rtti_PlotCurve, Rtti_PlotHistogram, Rtti_PlotSpectrogram, Rtti_PlotSVG, Rtti_PlotUserItem = 1000 } |
enum | ItemAttribute { Legend = 1, AutoScale = 2 } |
enum | RenderHint { RenderAntialiased = 1 } |
Public Member Functions | |
QwtPlotItem (const QwtText &title=QwtText()) | |
virtual | ~QwtPlotItem () |
void | attach (QwtPlot *plot) |
void | detach () |
QwtPlot * | plot () const |
void | setTitle (const QString &title) |
void | setTitle (const QwtText &title) |
const QwtText & | title () const |
virtual int | rtti () const |
void | setItemAttribute (ItemAttribute, bool on=true) |
bool | testItemAttribute (ItemAttribute) const |
void | setRenderHint (RenderHint, bool on=true) |
bool | testRenderHint (RenderHint) const |
double | z () const |
void | setZ (double z) |
void | show () |
void | hide () |
virtual void | setVisible (bool) |
bool | isVisible () const |
void | setAxis (int xAxis, int yAxis) |
void | setXAxis (int axis) |
int | xAxis () const |
void | setYAxis (int axis) |
int | yAxis () const |
virtual void | itemChanged () |
virtual void | draw (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &canvasRect) const =0 |
virtual QwtDoubleRect | boundingRect () const |
virtual void | updateLegend (QwtLegend *) const |
virtual void | updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &) |
virtual QWidget * | legendItem () const |
QwtDoubleRect | scaleRect (const QwtScaleMap &, const QwtScaleMap &) const |
QRect | paintRect (const QwtScaleMap &, const QwtScaleMap &) const |
QRect | transform (const QwtScaleMap &, const QwtScaleMap &, const QwtDoubleRect &) const |
QwtDoubleRect | invTransform (const QwtScaleMap &, const QwtScaleMap &, const QRect &) const |
Base class for items on the plot canvas.
A plot item is "something", that can be painted on the plot canvas, or only affects the scales of the plot widget. They can be categorized as:
Depending on the QwtPlotItem::ItemAttribute flags, an item is included into autoscaling or has an entry on the legnd.
Before misusing the existing item classes it might be better to implement a new type of plot item ( don't implement a watermark as spectrogram ). Deriving a new type of QwtPlotItem primarily means to implement the YourPlotItem::draw() method.
Plot Item Attributes
Render hints.
Runtime type information.
RttiValues is used to cast plot items, without having to enable runtime type information of the compiler.
Constructor
title | Title of the item |
QwtPlotItem::~QwtPlotItem | ( | ) | [virtual] |
Destroy the QwtPlotItem.
void QwtPlotItem::attach | ( | QwtPlot * | plot | ) |
Attach the item to a plot.
This method will attach a QwtPlotItem to the QwtPlot argument. It will first detach the QwtPlotItem from any plot from a previous call to attach (if necessary). If a NULL argument is passed, it will detach from any QwtPlot it was attached to.
plot | Plot widget |
QwtDoubleRect QwtPlotItem::boundingRect | ( | ) | const [virtual] |
Reimplemented in QwtPlotCurve, QwtPlotMarker, QwtPlotSpectrogram, and QwtPlotSvgItem.
void QwtPlotItem::detach | ( | ) | [inline] |
This method detaches a QwtPlotItem from any QwtPlot it has been associated with.
detach() is equivalent to calling attach( NULL )
virtual void QwtPlotItem::draw | ( | QPainter * | painter, | |
const QwtScaleMap & | xMap, | |||
const QwtScaleMap & | yMap, | |||
const QRect & | canvasRect | |||
) | const [pure virtual] |
Draw the item.
painter | Painter | |
xMap | Maps x-values into pixel coordinates. | |
yMap | Maps y-values into pixel coordinates. | |
canvasRect | Contents rect of the canvas in painter coordinates |
Implemented in QwtPlotCurve, QwtPlotGrid, QwtPlotMarker, QwtPlotRasterItem, QwtPlotScaleItem, QwtPlotSpectrogram, and QwtPlotSvgItem.
void QwtPlotItem::hide | ( | ) |
Hide the item.
QwtDoubleRect QwtPlotItem::invTransform | ( | const QwtScaleMap & | xMap, | |
const QwtScaleMap & | yMap, | |||
const QRect & | rect | |||
) | const |
Transform a rectangle from paint to scale coordinates
xMap | X map | |
yMap | Y map | |
rect | Rectangle in paint coordinates |
bool QwtPlotItem::isVisible | ( | ) | const |
void QwtPlotItem::itemChanged | ( | ) | [virtual] |
Update the legend and call QwtPlot::autoRefresh for the parent plot.
QWidget * QwtPlotItem::legendItem | ( | ) | const [virtual] |
Allocate the widget that represents the item on the legend.
The default implementation is made for QwtPlotCurve and returns a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().
Implements QwtLegendItemManager.
QRect QwtPlotItem::paintRect | ( | const QwtScaleMap & | xMap, | |
const QwtScaleMap & | yMap | |||
) | const |
Calculate the bounding paint rect of 2 maps.
xMap | X map | |
yMap | X map |
QwtPlot * QwtPlotItem::plot | ( | ) | const |
Return attached plot.
int QwtPlotItem::rtti | ( | ) | const [virtual] |
Return rtti for the specific class represented. QwtPlotItem is simply a virtual interface class, and base classes will implement this method with specific rtti values so a user can differentiate them.
The rtti value is useful for environments, where the runtime type information is disabled and it is not possible to do a dynamic_cast<...>.
Reimplemented in QwtPlotCurve, QwtPlotGrid, QwtPlotMarker, QwtPlotScaleItem, QwtPlotSpectrogram, and QwtPlotSvgItem.
QwtDoubleRect QwtPlotItem::scaleRect | ( | const QwtScaleMap & | xMap, | |
const QwtScaleMap & | yMap | |||
) | const |
Calculate the bounding scale rect of 2 maps.
xMap | X map | |
yMap | X map |
void QwtPlotItem::setAxis | ( | int | xAxis, | |
int | yAxis | |||
) |
Set X and Y axis
The item will painted according to the coordinates its Axes.
xAxis | X Axis | |
yAxis | Y Axis |
void QwtPlotItem::setItemAttribute | ( | ItemAttribute | attribute, | |
bool | on = true | |||
) |
Toggle an item attribute
attribute | Attribute type | |
on | true/false |
void QwtPlotItem::setRenderHint | ( | RenderHint | hint, | |
bool | on = true | |||
) |
Toggle an render hint
hint | Render hint | |
on | true/false |
void QwtPlotItem::setTitle | ( | const QwtText & | title | ) |
void QwtPlotItem::setTitle | ( | const QString & | title | ) |
void QwtPlotItem::setVisible | ( | bool | on | ) | [virtual] |
void QwtPlotItem::setXAxis | ( | int | axis | ) |
Set the X axis
The item will painted according to the coordinates its Axes.
axis | X Axis |
void QwtPlotItem::setYAxis | ( | int | axis | ) |
Set the Y axis
The item will painted according to the coordinates its Axes.
axis | Y Axis |
void QwtPlotItem::setZ | ( | double | z | ) |
Set the z value.
Plot items are painted in increasing z-order.
z | Z-value |
void QwtPlotItem::show | ( | ) |
Show the item.
bool QwtPlotItem::testItemAttribute | ( | ItemAttribute | attribute | ) | const |
Test an item attribute
attribute | Attribute type |
bool QwtPlotItem::testRenderHint | ( | RenderHint | hint | ) | const |
Test a render hint
hint | Render hint |
const QwtText & QwtPlotItem::title | ( | ) | const |
QRect QwtPlotItem::transform | ( | const QwtScaleMap & | xMap, | |
const QwtScaleMap & | yMap, | |||
const QwtDoubleRect & | rect | |||
) | const |
Transform a rectangle
xMap | X map | |
yMap | Y map | |
rect | Rectangle in scale coordinates |
void QwtPlotItem::updateLegend | ( | QwtLegend * | legend | ) | const [virtual] |
Update the widget that represents the item on the legend.
updateLegend() is called from itemChanged() to adopt the widget representing the item on the legend to its new configuration.
The default implementation is made for QwtPlotCurve and updates a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().
legend | Legend |
Implements QwtLegendItemManager.
Reimplemented in QwtPlotCurve.
void QwtPlotItem::updateScaleDiv | ( | const QwtScaleDiv & | , | |
const QwtScaleDiv & | ||||
) | [virtual] |
Update the item to changes of the axes scale division.
Update the item, when the axes of plot have changed. The default implementation does nothing, but items that depend on the scale division (like QwtPlotGrid()) have to reimplement updateScaleDiv()
xScaleDiv | Scale division of the x-axis | |
yScaleDiv | Scale division of the y-axis |
Reimplemented in QwtPlotGrid, and QwtPlotScaleItem.
int QwtPlotItem::xAxis | ( | ) | const |
Return xAxis.
int QwtPlotItem::yAxis | ( | ) | const |
Return yAxis.
double QwtPlotItem::z | ( | ) | const |
Plot items are painted in increasing z-order.