QCategoryAxis 類

The QCategoryAxis class places named ranges on the axis. 更多...

頭: #include <QCategoryAxis>
實例化: CategoryAxis
繼承: QValueAxis

公共類型

enum AxisLabelsPosition { AxisLabelsPositionCenter, AxisLabelsPositionOnValue }

特性

公共函數

QCategoryAxis (QObject * parent = nullptr)
virtual ~QCategoryAxis ()
void append (const QString & categoryLabel , qreal categoryEndValue )
QStringList categoriesLabels ()
int count () const
qreal endValue (const QString & categoryLabel ) const
QCategoryAxis::AxisLabelsPosition labelsPosition () const
void remove (const QString & categoryLabel )
void replaceLabel (const QString & oldLabel , const QString & newLabel )
void setLabelsPosition (QCategoryAxis::AxisLabelsPosition position )
void setStartValue (qreal min )
qreal startValue (const QString & categoryLabel = QString()) const

重實現公共函數

virtual QAbstractAxis::AxisType type () const

信號

void categoriesChanged ()
void labelsPositionChanged (QCategoryAxis::AxisLabelsPosition position )

靜態公共成員

const QMetaObject staticMetaObject

額外繼承成員

詳細描述

The QCategoryAxis class places named ranges on the axis.

This class can be used to explain the underlying data by adding labeled categories. Unlike QBarCategoryAxis , QCategoryAxis allows the widths of the category ranges to be specified freely.

Example code on how to use QCategoryAxis :

QChartView *chartView = new QChartView;
QLineSeries *series = new QLineSeries;
// ...
chartView->chart()->addSeries(series);
QCategoryAxis *axisY = new QCategoryAxis;
axisY->setMin(0);
axisY->setMax(52);
axisY->setStartValue(15);
axisY->append("First", 20);
axisY->append("Second", 37);
axisY->append("Third", 52);
chartView->chart()->setAxisY(axisY, series);
					

成員類型文檔編製

enum QCategoryAxis:: AxisLabelsPosition

此枚舉描述類彆標簽的位置。

常量 描述
QCategoryAxis::AxisLabelsPositionCenter 0x0 Labels are centered to category.
QCategoryAxis::AxisLabelsPositionOnValue 0x1 Labels are positioned to the high end limit of the category.

特性文檔編製

categoriesLabels : const QStringList

此特性以字符串列錶保持類彆標簽。

訪問函數:

QStringList categoriesLabels ()

count : const int

此特性保持類彆數。

訪問函數:

int count () const

labelsPosition : AxisLabelsPosition

This property holds the position of the category labels. The labels in the beginning and in the end of the axes may overlap other axes' labels when positioned on value.

訪問函數:

QCategoryAxis::AxisLabelsPosition labelsPosition () const
void setLabelsPosition (QCategoryAxis::AxisLabelsPosition position )

通知程序信號:

void labelsPositionChanged (QCategoryAxis::AxisLabelsPosition position )

startValue : qreal

This property holds the low end of the first category on the axis.

訪問函數:

qreal startValue (const QString & categoryLabel = QString()) const
void setStartValue (qreal min )

成員函數文檔編製

QCategoryAxis:: QCategoryAxis ( QObject * parent = nullptr)

Constructs an axis object that is a child of parent .

[虛擬] QCategoryAxis:: ~QCategoryAxis ()

銷毀對象。

void QCategoryAxis:: append (const QString & categoryLabel , qreal categoryEndValue )

Appends a new category to the axis with the label categoryLabel . A category label has to be unique. categoryEndValue specifies the high end limit of the category. It has to be greater than the high end limit of the previous category. Otherwise the method returns without adding a new category.

[signal] void QCategoryAxis:: categoriesChanged ()

This signal is emitted when the categories of the axis change.

QStringList QCategoryAxis:: categoriesLabels ()

Returns the list of the categories' labels.

注意: getter 函數對於特性 categoriesLabels .

int QCategoryAxis:: count () const

Returns the number of categories.

注意: getter 函數對於特性 count .

qreal QCategoryAxis:: endValue (const QString & categoryLabel ) const

Returns the high end limit of the category specified by categoryLabel .

void QCategoryAxis:: remove (const QString & categoryLabel )

Removes a category specified by the label categoryLabel from the axis.

void QCategoryAxis:: replaceLabel (const QString & oldLabel , const QString & newLabel )

Replaces an existing category label specified by oldLabel with newLabel . If the old label does not exist, the method returns without making any changes.

void QCategoryAxis:: setStartValue ( qreal min )

min to be the low end limit of the first category on the axis. If categories have already been added to the axis, the passed value must be less than the high end value of the already defined first category range. Otherwise nothing is done.

注意: setter 函數對於特性 startValue .

另請參閱 startValue ().

qreal QCategoryAxis:: startValue (const QString & categoryLabel = QString()) const

Returns the low end limit of the category specified by categoryLabel .

注意: getter 函數對於特性 startValue .

另請參閱 setStartValue ().

[虛擬] QAbstractAxis::AxisType QCategoryAxis:: type () const

重實現自 QValueAxis::type ().

返迴軸的類型。