- Qt 6.8
- Qt Graphs
- C++ Classes
- QtGraphs
- QBarSeries
- Qt Graphs | Commercial or GPLv3

# QBarSeries Class

The QBarSeries class presents data in bar graphs. More...

Header: | #include <QBarSeries>
CMake: | find_package(Qt6 REQUIRED COMPONENTS Graphs) target_link_libraries(mytarget PRIVATE Qt6::Graphs)
qmake: | QT += graphs
Instantiated By: | BarSeries
Inherits: | QAbstractSeries

- List of all members, including inherited members
- QBarSeries is part of Qt Graphs C++ Classes for 2D.

## Public Types

enum class | BarsOrientation { Vertical, Horizontal }
enum class | BarsType { Groups, Stacked, StackedPercent }
enum class | LabelsPosition { Center, InsideEnd, InsideBase, OutsideEnd }

## Properties

axisX : QAbstractAxis* axisY : QAbstractAxis* barComponent : QQmlComponent* barWidth : qreal barsOrientation : BarsOrientation barsType : BarsType count : const int | labelsAngle : qreal labelsFormat : QString labelsMargin : qreal labelsPosition : LabelsPosition labelsPrecision : int labelsVisible : bool

## Public Functions

| QBarSeries(QObject *parent = nullptr)
virtual | ~QBarSeries() override
bool | append(QBarSet *set)
bool | append(const QList<QBarSet *> &sets)
QAbstractAxis * | axisX()
QAbstractAxis * | axisY()
QQmlComponent * | barComponent() const
QList<QBarSet *> | barSets() const
qreal | barWidth() const
QBarSeries::BarsOrientation | barsOrientation() const
QBarSeries::BarsType | barsType() const
void | clear()
int | count() const
bool | insert(int index, QBarSet *set)
bool | isLabelsVisible() const
qreal | labelsAngle() const
QString | labelsFormat() const
qreal | labelsMargin() const
QBarSeries::LabelsPosition | labelsPosition() const
int | labelsPrecision() const
bool | remove(QBarSet *set)
void | setAxisX(QAbstractAxis *axis)
void | setAxisY(QAbstractAxis *axis)
void | setBarComponent(QQmlComponent *newBarComponent)
void | setBarWidth(qreal width)
void | setBarsOrientation(QBarSeries::BarsOrientation orientation)
void | setBarsType(QBarSeries::BarsType type)
void | setLabelsAngle(qreal angle)
void | setLabelsFormat(const QString &format)
void | setLabelsMargin(qreal margin)
void | setLabelsPosition(QBarSeries::LabelsPosition position)
void | setLabelsPrecision(int precision)
void | setLabelsVisible(bool visible = true)
bool | take(QBarSet *set)

## Reimplemented Public Functions

virtual QAbstractSeries::SeriesType | type() const override

## Signals

void | axisXChanged(QAbstractAxis *axis)
void | axisYChanged(QAbstractAxis *axis)
void | barComponentChanged()
void | barWidthChanged()
void | barsOrientationChanged(QBarSeries::BarsOrientation orientation)
void | barsTypeChanged(QBarSeries::BarsType type)
void | barsetsAdded(const QList<QBarSet *> &sets)
void | barsetsRemoved(const QList<QBarSet *> &sets)
void | clicked(int index, QBarSet *barset)
void | countChanged()
void | doubleClicked(int index, QBarSet *barset)
void | hovered(bool status, int index, QBarSet *barset)
void | labelsAngleChanged(qreal angle)
void | labelsFormatChanged(const QString &format)
void | labelsMarginChanged(qreal margin)
void | labelsPositionChanged(QBarSeries::LabelsPosition position)
void | labelsPrecisionChanged(int precision)
void | labelsVisibleChanged(bool visible)
void | pressed(int index, QBarSet *barset)
void | released(int index, QBarSet *barset)
void | restructuredBars()
void | setValueAdded(int index, int count, QBarSet *barset)
void | setValueChanged(int index, QBarSet *barset)
void | setValueRemoved(int index, int count, QBarSet *barset)
void | updatedBars()
void | updatedLayout()

## Detailed Description

This class draws data by default as a series of bars grouped by category, with one bar per category from each bar set added to the series. It also supports horizontal bars and grouping bars as stacked.

See also QBarSet and QAbstractSeries.

## Member Type Documentation

### enum class QBarSeries::BarsOrientation

This enum value describes the orientation of the bar series:

Constant | Value | Description
--- | --- | ---
`QBarSeries::BarsOrientation::Vertical` | `0` | Bars appear vertically.
`QBarSeries::BarsOrientation::Horizontal` | `1` | Bars appear horizontally.

### enum class QBarSeries::BarsType

This enum value describes the type of the bar series:

Constant | Value | Description
--- | --- | ---
`QBarSeries::BarsType::Groups` | `0` | Bar sets are grouped by category.
`QBarSeries::BarsType::Stacked` | `1` | Bar sets are stacked after each other by category.
`QBarSeries::BarsType::StackedPercent` | `2` | Bar sets are stacked after each other by category. The segment size corresponds to the percentage of the segment value compared with the total value of all segments in the stack.

### enum class QBarSeries::LabelsPosition

This enum value describes the position of the data value labels:

Constant | Value | Description
--- | --- | ---
`QBarSeries::LabelsPosition::Center` | `0` | Label is located in the center of the bar.
`QBarSeries::LabelsPosition::InsideEnd` | `1` | Label is located inside the bar at the top.
`QBarSeries::LabelsPosition::InsideBase` | `2` | Label is located inside the bar at the bottom.
`QBarSeries::LabelsPosition::OutsideEnd` | `3` | Label is located outside the bar at the top.

## Property Documentation

### axisX : QAbstractAxis*

X-axis of the series.

The x-axis used for the series. This should be QBarCategoryAxis.

Access functions:

QAbstractAxis * | axisX()
void | setAxisX(QAbstractAxis *axis)

Notifier signal:

void | axisXChanged(QAbstractAxis *axis)

### axisY : QAbstractAxis*

Y-axis of the series.

The y-axis used for the series. This should be QValueAxis.

Access functions:

QAbstractAxis * | axisY()
void | setAxisY(QAbstractAxis *axis)

Notifier signal:

void | axisYChanged(QAbstractAxis *axis)

### barComponent : QQmlComponent*

This property holds a custom QML component used for visualizing each of the bars. Instance of this component is created for each of the bar. To get access into bars properties, use BarComponent. When this is not defined, a default rectangle visualization for bars is used.

Access functions:

QQmlComponent * | barComponent() const
void | setBarComponent(QQmlComponent *newBarComponent)

Notifier signal:

void | barComponentChanged()

### barWidth : qreal

This property holds the width of the bars of the series.

The unit of width is the unit of the x-axis. The minimum width for bars is zero, and negative values are treated as zero. Setting the width to zero means that the width of the bar on the screen is one pixel regardless of the scale of the x-axis. Bars wider than zero are scaled using the x-axis scale.

By default, the barWidth is 0.5 (bars will take 50% of the available width). The valid values range from 0.0 (0%) to 1.0 (100%).

Note: When used with QBarSeries, this value specifies the width of a group of bars instead of that of a single bar.

Access functions:

qreal | barWidth() const
void | setBarWidth(qreal width)

Notifier signal:

void | barWidthChanged()

See also QBarSeries.

### barsOrientation : BarsOrientation

This property holds the orientation of the bar series. By default the bars appear vertically.

Access functions:

QBarSeries::BarsOrientation | barsOrientation() const
void | setBarsOrientation(QBarSeries::BarsOrientation orientation)

Notifier signal:

void | barsOrientationChanged(QBarSeries::BarsOrientation orientation)

### barsType : BarsType

This property holds the type of the bar series.

Access functions:

QBarSeries::BarsType | barsType() const
void | setBarsType(QBarSeries::BarsType type)

Notifier signal:

void | barsTypeChanged(QBarSeries::BarsType type)

### `[read-only]` count : const int

This property holds the number of bar sets in a bar series.

Access functions:

int | count() const

Notifier signal:

void | countChanged()

### labelsAngle : qreal

This property holds the angle of the value labels in degrees.

Access functions:

qreal | labelsAngle() const
void | setLabelsAngle(qreal angle)

Notifier signal:

void | labelsAngleChanged(qreal angle)

### labelsFormat : QString

This property holds the format used for showing labels in a bar series.

QBarSeries supports the following format tag:

@value | The value of the bar

For example, the following usage of the format tags would produce labels that show the value followed by the unit (u):

     series->setLabelsFormat("@value u");

By default, the labels show the value of the bar. For the percent bar series, % is added after the value. The labels are shown on the plot area, if the bars are close to each other, the labels may overlap.

Access functions:

QString | labelsFormat() const
void | setLabelsFormat(const QString &format)

Notifier signal:

void | labelsFormatChanged(const QString &format)

See also labelsVisible, labelsPosition, and labelsPrecision.

### labelsMargin : qreal

This property holds the margin of the value labels in pixels.

This margin from side is used when labelsPosition is set to something else than `LabelsPosition.Center`. The default value is `0`.

Access functions:

qreal | labelsMargin() const
void | setLabelsMargin(qreal margin)

Notifier signal:

void | labelsMarginChanged(qreal margin)

### labelsPosition : LabelsPosition

This property holds the position of value labels.

Access functions:

QBarSeries::LabelsPosition | labelsPosition() const
void | setLabelsPosition(QBarSeries::LabelsPosition position)

Notifier signal:

void | labelsPositionChanged(QBarSeries::LabelsPosition position)

See also labelsVisible and labelsFormat.

### labelsPrecision : int

This property holds the maximum amount of significant digits shown in value labels.

Default value is 6.

Access functions:

int | labelsPrecision() const
void | setLabelsPrecision(int precision)

Notifier signal:

void | labelsPrecisionChanged(int precision)

### labelsVisible : bool

This property holds the visibility of the labels in a bar series. The default label visibility is `false`.

Access functions:

bool | isLabelsVisible() const
void | setLabelsVisible(bool visible = true)

Notifier signal:

void | labelsVisibleChanged(bool visible)

## Member Function Documentation

### `[explicit]` QBarSeries::QBarSeries(QObject *parent = nullptr)

Constructs an empty bar series that is a QObject and a child of parent.

### `[override virtual noexcept]` QBarSeries::~QBarSeries()

Removes the bar series and the bar sets owned by it.

### bool QBarSeries::append(QBarSet *set)

Adds a set of bars specified by set to the bar series and takes ownership of it. If the set is null or it already belongs to the series, it will not be appended. Returns `true` if appending succeeded.

### bool QBarSeries::append(const QList<QBarSet *> &sets)

Adds a list of bar sets specified by sets to a bar series and takes ownership of the sets. Returns `true` if all sets were appended successfully. If any of the sets is null or was previously appended to the series, nothing is appended and this function returns `false`. If any of the sets appears in the list more than once, nothing is appended and this function returns `false`.

### QList<QBarSet *> QBarSeries::barSets() const

Returns a list of bar sets in a bar series. Keeps the ownership of the bar sets.

### qreal QBarSeries::barWidth() const

Returns the width of the bars of the series.

Note: Getter function for property barWidth.

See also setBarWidth().

### `[signal]` void QBarSeries::barWidthChanged()

This signal is emitted when the bar width changes.

Note: Notifier signal for property barWidth.

### `[signal]` void QBarSeries::barsetsAdded(const QList<QBarSet *> &sets)

This signal is emitted when the bar sets specified by sets are added to the series.

See also append() and insert().

### `[signal]` void QBarSeries::barsetsRemoved(const QList<QBarSet *> &sets)

This signal is emitted when the bar sets specified by sets are removed from the series.

See also remove().

### void QBarSeries::clear()

Removes all bar sets from the series and permanently deletes them.

### `[signal]` void QBarSeries::clicked(int index, QBarSet *barset)

This signal is emitted when the user clicks the bar specified by index in the bar set specified by barset.

### int QBarSeries::count() const

Returns the number of bar sets in a bar series.

Note: Getter function for property count.

### `[signal]` void QBarSeries::countChanged()

This signal is emitted when the number of bar sets is changed, for example by append() or remove().

Note: Notifier signal for property count.

### `[signal]` void QBarSeries::doubleClicked(int index, QBarSet *barset)

This signal is emitted when the user double-clicks the bar specified by index in the bar set specified by barset.

### `[signal]` void QBarSeries::hovered(bool status, int index, QBarSet *barset)

This signal is emitted when a mouse is hovered over the bar specified by index in the bar set specified by barset. When the mouse moves over the bar, status turns `true`, and when the mouse moves away again, it turns `false`.

### bool QBarSeries::insert(int index, QBarSet *set)

Inserts a bar set specified by set to a series at the position specified by index and takes ownership of the set. If the set is null or already belongs to the series, it will not be appended. Returns `true` if inserting succeeds.

### bool QBarSeries::isLabelsVisible() const

Returns the visibility of labels.

Note: Getter function for property labelsVisible.

### `[signal]` void QBarSeries::labelsAngleChanged(qreal angle)

This signal is emitted when the angle of the value labels changes.

Note: Notifier signal for property labelsAngle.

### `[signal]` void QBarSeries::labelsFormatChanged(const QString &format)

This signal is emitted when the format of data value labels changes.

Note: Notifier signal for property labelsFormat.

### `[signal]` void QBarSeries::labelsMarginChanged(qreal margin)

This signal is emitted when the margin of the value labels changes.

Note: Notifier signal for property labelsMargin.

### `[signal]` void QBarSeries::labelsPositionChanged(QBarSeries::LabelsPosition position)

This signal is emitted when the position of value labels changes.

Note: Notifier signal for property labelsPosition.

### `[signal]` void QBarSeries::labelsPrecisionChanged(int precision)

This signal is emitted when the precision of the value labels changes.

Note: Notifier signal for property labelsPrecision.

### `[signal]` void QBarSeries::labelsVisibleChanged(bool visible)

This signal is emitted when the labels' visibility changes to visible.

Note: Notifier signal for property labelsVisible.

See also isLabelsVisible() and setLabelsVisible().

### `[signal]` void QBarSeries::pressed(int index, QBarSet *barset)

This signal is emitted when the user clicks the bar specified by index in the bar set specified by barset and holds down the mouse button.

### `[signal]` void QBarSeries::released(int index, QBarSet *barset)

This signal is emitted when the user releases the mouse press on the bar specified by index in the bar set specified by barset.

### bool QBarSeries::remove(QBarSet *set)

Removes the bar set specified by set from the series and permanently deletes it if the removal succeeds. Returns `true` if the set was removed.

### `[signal]` void QBarSeries::restructuredBars()

This signal is emitted when the bars are restructured.

### void QBarSeries::setBarWidth(qreal width)

Sets the width of the bars of the series to width.

Note: Setter function for property barWidth.

See also barWidth().

### void QBarSeries::setLabelsVisible(bool visible = true)

Sets the visibility of labels in a bar series to visible.

Note: Setter function for property labelsVisible.

See also isLabelsVisible().

### `[signal]` void QBarSeries::setValueAdded(int index, int count, QBarSet *barset)

This signal is emitted when a barset's value is changed. index is the index of the barset in the series. The number of the added values is indicated count. The barset is a pointer to the changed set.

### `[signal]` void QBarSeries::setValueChanged(int index, QBarSet *barset)

This signal is emitted when a barset's value is changed. index is the index of the barset in the series. The barset is a pointer to the changed set.

### `[signal]` void QBarSeries::setValueRemoved(int index, int count, QBarSet *barset)

This signal is emitted when a barset's value is changed. index is the index of the barset in the series. The number of the removed values is indicated count. The barset is a pointer to the changed set.

### bool QBarSeries::take(QBarSet *set)

Takes a single set from the series. Does not delete the bar set object.

Note: The series remains the barset's parent object. You must set the parent object to take full ownership.

Returns `true` if the take operation succeeds.

### `[override virtual]` QAbstractSeries::SeriesType QBarSeries::type() const

Reimplements an access function for property: QAbstractSeries::type.

Returns the bar series.

### `[signal]` void QBarSeries::updatedBars()

This signal is emitted when bars are updated.

### `[signal]` void QBarSeries::updatedLayout()

This signal is emitted when the layout is updated.