QVBarModelMapper Class

The QVBarModelMapper class is a vertical model mapper for bar series. More...

Header: #include <QVBarModelMapper>
Instantiated By: VBarModelMapper
Inherits: QObject

Properties

Public Functions

QVBarModelMapper(QObject *parent = nullptr)
int firstBarSetColumn() const
int firstRow() const
int lastBarSetColumn() const
QAbstractItemModel *model() const
int rowCount() const
QAbstractBarSeries *series() const
void setFirstBarSetColumn(int firstBarSetColumn)
void setFirstRow(int firstRow)
void setLastBarSetColumn(int lastBarSetColumn)
void setModel(QAbstractItemModel *model)
void setRowCount(int rowCount)
void setSeries(QAbstractBarSeries *series)

Signals

Detailed Description

Model mappers enable using a data model derived from the QAbstractItemModel class as a data source for a chart. A vertical model mapper is used to create a connection between a data model and QAbstractBarSeries, so that each column in the data model defines a bar set and each row maps to a category in a bar series.

Both model and bar series properties can be used to manipulate the data. The model mapper keeps the bar series and the data model in sync.

The model mapper ensures that all the bar sets in the bar series have equal sizes. Therefore, adding or removing a value from a bar set causes the same change to be made in all the bar sets in the bar series.

For more information, see BarModelMapper Example.

See also QHBarModelMapper.

Property Documentation

firstBarSetColumn : int

This property holds the column of the model that is used as the data source for the first bar set.

The default value is -1 (invalid mapping).

Access functions:

int firstBarSetColumn() const
void setFirstBarSetColumn(int firstBarSetColumn)

Notifier signal:

firstRow : int

This property holds the row of the model that contains the first values of the bar sets in the bar series.

The minimum and default value is 0.

Access functions:

int firstRow() const
void setFirstRow(int firstRow)

Notifier signal:

lastBarSetColumn : int

This property holds the column of the model that is used as the data source for the last bar set.

The default value is -1 (invalid mapping).

Access functions:

int lastBarSetColumn() const
void setLastBarSetColumn(int lastBarSetColumn)

Notifier signal:

model : QAbstractItemModel*

This property holds the data model that is used by the mapper.

Access functions:

QAbstractItemModel *model() const
void setModel(QAbstractItemModel *model)

Notifier signal:

void modelReplaced()

rowCount : int

This property holds the number of rows of the model that are mapped as the data for the bar series.

The minimum and default value is -1 (number limited to the number of rows in the model).

Access functions:

int rowCount() const
void setRowCount(int rowCount)

Notifier signal:

series : QtCharts::QAbstractBarSeries*

This property holds the bar series that is used by the mapper.

All the data in the series is discarded when it is set to the mapper. When a new series is specified, the old series is disconnected (but it preserves its data).

Access functions:

QAbstractBarSeries *series() const
void setSeries(QAbstractBarSeries *series)

Notifier signal:

Member Function Documentation

QVBarModelMapper::QVBarModelMapper(QObject *parent = nullptr)

Constructs a mapper object that is a child of parent.

[signal] void QVBarModelMapper::firstBarSetColumnChanged()

This signal is emitted when the first bar set column changes.

Note: Notifier signal for property firstBarSetColumn.

[signal] void QVBarModelMapper::firstRowChanged()

This signal is emitted when the first row changes.

Note: Notifier signal for property firstRow.

[signal] void QVBarModelMapper::lastBarSetColumnChanged()

This signal is emitted when the last bar set column changes.

Note: Notifier signal for property lastBarSetColumn.

[signal] void QVBarModelMapper::modelReplaced()

This signal is emitted when the model that the mapper is connected to changes.

Note: Notifier signal for property model.

[signal] void QVBarModelMapper::rowCountChanged()

This signal is emitted when the number of rows changes.

Note: Notifier signal for property rowCount.

[signal] void QVBarModelMapper::seriesReplaced()

This signal is emitted when the bar series that the mapper is connected to changes.

Note: Notifier signal for property series.