class QCategoryAxis#

The QCategoryAxis class places named ranges on the axis. More

Inheritance diagram of PySide6.QtCharts.QCategoryAxis

Synopsis#

Properties#

  • categoriesLabelsᅟ - Category labels as a string list

  • countᅟ - Number of categories

  • labelsPositionᅟ - 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

  • startValueᅟ - Low end of the first category on the axis

Methods#

Signals#

Note

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Detailed Description#

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 :

../../_images/api_category_axis.png
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);
class AxisLabelsPosition#

This enum describes the position of the category labels.

Constant

Description

QCategoryAxis.AxisLabelsPositionCenter

Labels are centered to category.

QCategoryAxis.AxisLabelsPositionOnValue

Labels are positioned to the high end limit of the category.

Note

Properties can be used directly when from __feature__ import true_property is used or via accessor functions otherwise.

property categoriesLabelsᅟ: list of strings#

This property holds The category labels as a string list..

Access functions:
property countᅟ: int#

This property holds The number of categories..

Access functions:
property labelsPositionᅟ: QCategoryAxis.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..

Access functions:
property startValueᅟ: float#

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

Access functions:
__init__([parent=None])#
Parameters:

parentQObject

Constructs an axis object that is a child of parent.

append(label, categoryEndValue)#
Parameters:
  • label – str

  • categoryEndValue – float

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.

categoriesChanged()#

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

categoriesLabels()#
Return type:

list of strings

Returns the list of the categories’ labels.

Getter of property categoriesLabelsᅟ .

count()#
Return type:

int

Returns the number of categories.

Getter of property countᅟ .

endValue(categoryLabel)#
Parameters:

categoryLabel – str

Return type:

float

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

labelsPosition()#
Return type:

AxisLabelsPosition

Getter of property labelsPositionᅟ .

labelsPositionChanged(position)#
Parameters:

positionAxisLabelsPosition

Notification signal of property labelsPositionᅟ .

remove(label)#
Parameters:

label – str

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

replaceLabel(oldLabel, newLabel)#
Parameters:
  • oldLabel – str

  • newLabel – str

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

setLabelsPosition(position)#
Parameters:

positionAxisLabelsPosition

See also

labelsPosition()

Setter of property labelsPositionᅟ .

setStartValue(min)#
Parameters:

min – float

Sets 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.

See also

startValue()

Setter of property startValueᅟ .

startValue([categoryLabel=""])#
Parameters:

categoryLabel – str

Return type:

float

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

See also

setStartValue()