QwtPlotItemInfo类 参考

Utility class for querying QwtPlotItem types and filtering plot items 更多...

#include <qwt_plot_item_info.h>

静态 Public 成员函数
static bool	isSeriesItem (const QwtPlotItem *item)
	Check whether the item is a QwtPlotSeriesItem subclass
static bool	isXYSeriesItem (const QwtPlotItem *item)
	Check whether the item stores QPointF data
static bool	isIntervalSeriesItem (const QwtPlotItem *item)
	Check whether the item stores QwtIntervalSample data
static bool	isDecoratorItem (const QwtPlotItem *item)
	Check whether the item is a decorator (non-data item)
static bool	isDataItem (const QwtPlotItem *item)
	Check whether the item holds any data series
static QwtPlotItemList	seriesItems (const QwtPlot *plot)
	Get all QwtPlotSeriesItem instances from a plot
static QwtPlotItemList	xySeriesItems (const QwtPlot *plot)
	Get all QPointF-based series items from a plot
static QwtPlotItemList	filterByRtti (const QwtPlot *plot, int rtti)
	Filter items by a single rtti value
static QwtPlotItemList	filterByRtti (const QwtPlot *plot, const QSet< int > &rttiSet)
	Filter items by a set of rtti values
static QwtPlotItemList	visibleItems (const QwtPlot *plot)
	Get all currently visible items from a plot
static int	dataSize (const QwtPlotItem *item)
	Get the number of data samples in a plot item
static QRectF	dataRect (const QwtPlotItem *item)
	Get the bounding rectangle of the item's data
static QString	rttiName (int rtti)
	Get a human-readable name for an rtti value

详细描述

Utility class for querying QwtPlotItem types and filtering plot items

QwtPlotItemInfo provides static methods to determine the runtime type of plot items, filter items by category, and retrieve basic information such as data size and bounding rectangle. This class does not modify any plot or item state.

QwtPlot* plot = ...;
QwtPlotItemList curves = Qwt::QwtPlotItemInfo::xySeriesItems(plot);
for (auto* item : curves) {
    qDebug() << item->title().text()
             << "has" << Qwt::QwtPlotItemInfo::dataSize(item) << "points";
}

参见

QwtPlotDataAccess, QwtPlotStyling

成员函数说明

dataRect()

QRectF QwtPlotItemInfo::dataRect ( const QwtPlotItem *  item )

static

Get the bounding rectangle of the item's data

参数

item	Plot item to query

返回

Bounding rectangle, or an invalid QRectF if the item does not hold data

dataSize()

int QwtPlotItemInfo::dataSize ( const QwtPlotItem *  item )

static

Get the number of data samples in a plot item

参数

item	Plot item to query

返回

Number of samples, or -1 if the item does not hold a data series

filterByRtti() [1/2]

QwtPlotItemList QwtPlotItemInfo::filterByRtti ( const QwtPlot *  plot, const QSet< int > &  rttiSet  )

static

Filter items by a set of rtti values

参数

plot	Plot to query
rttiSet	Set of rtti values to match

返回

List of items whose rtti is in the set

filterByRtti() [2/2]

QwtPlotItemList QwtPlotItemInfo::filterByRtti ( const QwtPlot *  plot, int  rtti  )

static

Filter items by a single rtti value

参数

plot	Plot to query
rtti	Runtime type value to match

返回

List of items matching the rtti

参见

QwtPlotDict::itemList(int)

isDataItem()

bool QwtPlotItemInfo::isDataItem ( const QwtPlotItem *  item )

static

Check whether the item holds any data series

参数

item	Plot item to check

返回

true for all QwtPlotSeriesItem subclasses

参见

isSeriesItem()

isDecoratorItem()

bool QwtPlotItemInfo::isDecoratorItem ( const QwtPlotItem *  item )

static

Check whether the item is a decorator (non-data item)

参数

item	Plot item to check

返回

true for grid, marker, scale, legend, text label, zone, shape, graphic, arrow marker

isIntervalSeriesItem()

bool QwtPlotItemInfo::isIntervalSeriesItem ( const QwtPlotItem *  item )

static

Check whether the item stores QwtIntervalSample data

参数

item	Plot item to check

返回

true for QwtPlotIntervalCurve and QwtPlotHistogram

isSeriesItem()

bool QwtPlotItemInfo::isSeriesItem ( const QwtPlotItem *  item )

static

Check whether the item is a QwtPlotSeriesItem subclass

参数

item	Plot item to check, may be nullptr

返回

true if item is derived from QwtPlotSeriesItem

isXYSeriesItem()

bool QwtPlotItemInfo::isXYSeriesItem ( const QwtPlotItem *  item )

static

Check whether the item stores QPointF data

参数

item	Plot item to check

返回

true for QwtPlotCurve and QwtPlotBarChart

rttiName()

QString QwtPlotItemInfo::rttiName ( int  rtti )

static

Get a human-readable name for an rtti value

参数

rtti	Runtime type value

返回

String name such as "PlotCurve", "PlotBarChart", etc.

seriesItems()

QwtPlotItemList QwtPlotItemInfo::seriesItems ( const QwtPlot *  plot )

static

Get all QwtPlotSeriesItem instances from a plot

参数

plot	Plot to query

返回

List of series items

visibleItems()

QwtPlotItemList QwtPlotItemInfo::visibleItems ( const QwtPlot *  plot )

static

Get all currently visible items from a plot

参数

plot	Plot to query

返回

List of visible items

xySeriesItems()

QwtPlotItemList QwtPlotItemInfo::xySeriesItems ( const QwtPlot *  plot )

static

Get all QPointF-based series items from a plot

参数

plot	Plot to query

返回

List of XY series items (curves and bar charts)

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该类的文档由以下文件生成:

• /home/runner/work/QWT/QWT/src/plot/qwt_plot_item_info.h
• /home/runner/work/QWT/QWT/src/plot/qwt_plot_item_info.cpp