AbstractBarSeries QML Type

An abstract parent type for all bar series types. More...

Properties

Signals

Methods

  • BarSet append(string label, VariantList values)
  • BarSet at(int index)
  • clear()
  • BarSet insert(int index, string label, VariantList values)
  • bool remove(BarSet barset)

Detailed Description

In bar charts, bars are defined as bar sets that contain one data value for each category. The position of a bar is specified by the category and its height by the data value. Bar series that contain multiple bar sets group together bars that belong to the same category. The way the bars are displayed is determined by the type chosen to create the bar chart: BarSeries, StackedBarSeries, PercentBarSeries, HorizontalBarSeries, HorizontalStackedBarSeries, or HorizontalPercentBarSeries.

If a ValueAxis type is used instead of a BarCategoryAxis type for the main bar axis, the bars are grouped around the index value of the category.

The following QML code snippet shows how to use the BarSeries and BarCategoryAxis type to create a simple bar chart:

 ChartView {
     title: "Bar Chart"
     anchors.fill: parent
     legend.alignment: Qt.AlignBottom
     antialiasing: true

     BarSeries {
         id: mySeries
         axisX: BarCategoryAxis { categories: ["2007", "2008", "2009", "2010", "2011", "2012" ] }
         BarSet { label: "Bob"; values: [2, 2, 3, 4, 5, 6] }
         BarSet { label: "Susan"; values: [5, 1, 2, 4, 1, 7] }
         BarSet { label: "James"; values: [3, 5, 8, 13, 5, 8] }
     }
 }


Property Documentation

axisX : AbstractAxis

The x-axis used for the series. If you leave both axisX and axisXTop undefined, a BarCategoryAxis is created for the series.

See also axisXTop.


axisXTop : AbstractAxis

The x-axis used for the series, drawn on top of the chart view.

Note: You can only provide either axisX or axisXTop, but not both.

See also axisX.


axisY : AbstractAxis

The y-axis used for the series. If you leave both axisY and axisYRight undefined, a ValueAxis is created for the series.

See also axisYRight.


axisYRight : AbstractAxis

The y-axis used for the series, drawn to the right of the chart view.

Note: You can only provide either axisY or axisYRight, but not both.

See also axisY.


barWidth : real

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.

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


count : int [read-only]

The number of bar sets in a bar series.


labelsAngle : real

The angle of the value labels in degrees.


labelsFormat : string

The format used for showing labels in a bar series.

See also QAbstractBarSeries::labelsFormat, labelsVisible, and labelsPosition.


labelsPosition : enumeration

The position of the data value labels:

ConstantDescription
AbstractBarSeries.LabelsCenterLabel is located in the center of the bar.
AbstractBarSeries.LabelsInsideEndLabel is located inside the bar at the top.
AbstractBarSeries.LabelsInsideBaseLabel is located inside the bar at the bottom.
AbstractBarSeries.LabelsOutsideEndLabel is located outside the bar at the top.

See also labelsVisible and labelsFormat.


labelsPrecision : real

The maximum amount of significant digits shown in value labels.

Default value is 6.


labelsVisible : bool

The visibility of the labels in a bar series.


Signal Documentation

barsetsAdded()

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

The corresponding signal handler is onBarsetsAdded.

Note: The corresponding handler is onBarsetsAdded.


barsetsRemoved()

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

The corresponding signal handler is onBarsetsRemoved.

Note: The corresponding handler is onBarsetsRemoved.


clicked(int index, BarSet barset)

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

The corresponding signal handler is onClicked.

Note: The corresponding handler is onClicked.


doubleClicked(int index, BarSet barset)

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

The corresponding signal handler is onDoubleClicked.

Note: The corresponding handler is onDoubleClicked.


hovered(bool status, int index, BarSet 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.

The corresponding signal handler is onHovered.

Note: The corresponding handler is onHovered.


pressed(int index, BarSet 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.

The corresponding signal handler is onPressed.

Note: The corresponding handler is onPressed.


released(int index, BarSet 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.

The corresponding signal handler is onReleased.

Note: The corresponding handler is onReleased.


Method Documentation

BarSet append(string label, VariantList values)

Adds a new bar set with label and values to the index. values is a list of real values.

For example:

 myBarSeries.append("set 1", [0, 0.2, 0.2, 0.5, 0.4, 1.5, 0.9]);

BarSet at(int index)

Returns the bar set at index. Returns null if the index is not valid.


clear()

Removes all bar sets from the series.


BarSet insert(int index, string label, VariantList values)

Adds a new bar set with label and values to index. values can be a list of real values or a list of XYPoint types.

If the index value is equal to or less than zero, the new bar set is prepended to the bar series. If the index value is equal to or greater than the number of bar sets in the bar series, the new bar set is appended to the bar series.

See also append().


bool remove(BarSet barset)

Removes the bar set specified by barset from the series. Returns true if successful, false otherwise.