JavaScript/jQuery PolarChart Options

When adapting to small container size, the widget may hide its accessory elements, thus saving space for more valuable ones. The elements are being hidden in the following sequence.

1. Title
2. Export menu icon
3. Legend
4. Argument axis labels
5. Point labels (can be saved by setting the adaptiveLayout.keepLabels option to true)

To specify the widget's size small enough for the layout to begin adapting, use the height and width options of the adaptiveLayout object.

View Demo on JSFiddle

The widget animate its elements at the beginning of its lifetime and when the data source changes.

For charting, the polar coordinate system is used to determine each point uniquely on a plane through two numbers, the argument and the value of the point. A circular and straight lines (the axis of arguments and the axis of values) are specified to define the coordinates. To define the argument axis, use the argumentAxis configuration object. To define the value axis, use the valueAxis configuration object. To set the properties of all axes to a common value, use the commonAxisSettings configuration object. This object exposes the properties that can be specified for all axes simultaneously. Note that the value specified for an axis individually (in the argumentAxis or valueAxis object) overrides the value specified in the commonAxisSettings object.

Works only if the equalBarWidth option is set to true.

Use this object's properties to set the options for all chart axes at once. The option values will be applied to the argument axis and all values axes, which are defined in the valueAxis array. To set a common axis option for an axis individually, use the corresponding valueAxis or argumentAxis object. Values that are set individually override their corresponding common values.

Use this object's properties to set options for all chart series at once. These can be options common to all series types and options specific to series types.

If you have several series of one type, you can set options to the values specific to this series type using the corresponding object (area, line or another) within the commonSeriesSettings configuration object. The values that are set within type-specific configuration objects override the corresponding common values.

In case you have to set an option for an individual series, use the corresponding series object within the series array. The values that are set individually override the corresponding common values.

If you set this property to the color of the parent page element, certain chart elements will use this color to coordinate with the page. For example, hovered points in the PolarChart widget are painted in the color that is set to this property, but you can change this color to a custom color (see color).

All point labels in a chart are identical by default, but you can specify a unique appearance for individual labels using the customizeLabel function. This function should return an object with options that will be changed for a certain label. See the label object for information about all options available for changing.

The customizeLabel function accepts an object providing information about the series point that the label belongs to. This object contains the following fields.

By default, all series points in a chart are identical, but you can specify a unique appearance for individual points using the customizePoint function. This function should return an object with options that will be changed for a certain point. See the point object for information about all options available for changing.

The customizePoint function accepts an object providing information about the series point. This object contains the following fields.

When values from a data source are of a different type, they may be displayed incorrectly on a chart. To resolve this situation, use the options provided by the dataPrepareSettings configuration object. You can enable/disable data validation using the checkTypeForAllData option, or specify whether or not to convert the data source values to the type of the axis using the convertToAxisDataType option. In addition, you can sort the series points using the sortingMethod option.

This option accepts one of the following:

• Array of objects
  A simple JavaScript array containing a collection of plain objects. See demo.

• URL
  A URL to JSON data or a service returning data in JSON format. See demo.

• DataSource or its configuration object
  A DataSource is an object that provides an API for data processing. Learn more about it from the Data Layer and DataSource Examples guides. See demo.

  NOTE

  Turn the DataSource's pagination off to prevent data from partitioning.

See Also

• argumentField | valueField
• getDataSource()

You can configure this option in an ASP.NET MVC Control as follows:

@(Html.DevExtreme().WidgetName()
    .ElementAttr("class", "class-name")
    // ===== or =====
    .ElementAttr(new {
        @id = "elementId",
        @class = "class-name"
    })
    // ===== or =====
    .ElementAttr(new Dictionary<string, object>() {
        { "id", "elementId" },
        { "class", "class-name" }
    })

)

@(Html.DevExtreme().WidgetName() _
    .ElementAttr("class", "class-name")
    ' ===== or =====
    .ElementAttr(New With {
        .id = "elementId",
        .class = "class-name"
    })
    ' ===== or =====
    .ElementAttr(New Dictionary(Of String, Object) From {
        { "id", "elementId" },
        { "class", "class-name" }
    })
)

If some values for a series are set to zero or not specified, bars that represent these values will be missing from the chart. To fill the empty area by extending the angle of the neighboring bars, set the equalBarWidth property to false. The bars will have different angles, but there will be no empty areas.

To set a custom angle for bars, as well as the spacing between bars, use the barWidth option.

If the widget's container is not large enough to contain bars of the specified width along with the specified spacing between them, the spacing will be ignored.

These features allow a user to export your widget into a document or print it. When exporting is enabled, the "Exporting/Printing" button appears in the widget. A click on it invokes a drop-down menu that lists exporting and printing commands. The following formats are supported for exporting into: PNG, PDF, JPEG, SVG and GIF.

See Also

• exportTo(fileName, format)
• print()
• DevExpress.viz.exportFromMarkup(markup, options)

Watch Video

The PolarChart widget can include a legend - an explanatory component that helps you identify a series. Each series is represented by an item on a Legend. An item marker identifies the series color. An item label displays the series title. To set the required position for a legend and its items, to customize the font settings for item labels, and to specify the size of item markers, use the properties of the legend configuration object. To learn more on the legend and its options, refer to the Legend topic.

When the widget visualizes local data, loading is instant. But when the widget is bound to a remote data source, loading may takes a considerable amount of time. To keep the viewer's attention, the widget can display a loading indicator.

To activate the loading indicator, assign true to the loadingIndicator.show option. Once data is loaded, the loading indicator will be hidden automatically.

See Also

• showLoadingIndicator()
• hideLoadingIndicator()

Oftentimes, series data contains negative values. Visualizing such data using stacked-like series may lead to unexpected results. To prevent situations of this kind, assign true to the negativesAsZeroes option, and the widget will count all negative values as zeroes.

When implementing a handling function, use the object passed to it as the parameter. You can find the value of the clicked label among fields of this object.

Alternatively, you can navigate to a specific URL when the argumentAxisClick event fires. For this purpose, assign this URL to the onArgumentAxisClick option.

See Also

• getAllSeries()
• getSeriesByName(seriesName)
• getSeriesByPos(seriesIndex)

See Also

• onExporting
• onFileSaving

See Also

• onExported
• onFileSaving

See Also

• onExporting
• onExported

When an error or warning appears, the widget notifies you by passing a message to the browser console. This message contains the ID of the incident, a brief description, and a link to the Errors and Warnings section where further information about this incident can be found. However, you can handle errors and warnings in the way that you require. To do this, implement a callback function performing the required actions and assign it to the onIncidentOccurred option. Within this function, you can use information about the incident that occurred. This information can be accessed from the target field of the object passed to the callback function as a parameter. This information includes the following.

• id
  Contains the ID of the incident. The full list of IDs can be found in the Errors and Warnings section.
• type
  Contains the type of the incident. This field equals "error" for errors or "warning" for warnings.
• args
  Contains the argument of the incident's message. The content of this field varies greatly, depending on the incident. For example, it may contain the name of the data source field that was not specified correctly, or the name of the option that was not set properly.
• text
  Contains the text passed to the browser console. This text includes the content of the args field, if there are any.
• widget
  Contains the name of the widget that produced the error or warning.
• version
  Contains the currently used version of the DevExtreme library.

You cannot access widget elements in this handler because it is executed before they are ready. Use the onDrawn handler instead.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the series to which the clicked legend item belongs. To learn about series members you can use, refer to the description of the Series object.

Alternatively, you can navigate to a specific URL when the legendClick event fires. For this purpose, assign this URL to the onLegendClick option.

To learn more about handling click operations, and to see an example, refer to the Click Handling topic.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the clicked series point. To learn about point's members that you can use, refer to the description of the Point object.

Alternatively, you can navigate to a specific URL when the pointClick event fires. For this purpose, assign this URL to the onPointClick option.

To learn more about how to handle click operations, and to see an example, refer to the Click Handling topic.

View Demo

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the series point whose hover state has been changed. To identify whether this point was hovered over or hovered out, call its isHovered() method. To discover point fields and methods, refer to the Point class description.

To learn more about how to handle hover operations, refer to the Hover Handling topic.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the series point whose selection state has been changed. To identify whether this point was selected or deselected, call its isSelected() method. To discover point fields and methods that you can use, refer to the Point class description.

To learn more about how to handle selection, refer to the Selection Handling topic.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the clicked series. To learn about series members that you can use, refer to the description of the Series object.

Alternatively, you can navigate to a specific URL when the seriesClick event fires. For this purpose, assign this URL to the onSeriesClick option.

To learn more about handling click operations, and to see an example, refer to the Click Handling topic.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the series whose hover state has been changed. To identify whether this series was hovered over or hovered out, call its isHovered() method. To discover series fields and methods, refer to the Series class description.

To learn more about how to handle hover operations, refer to the Hover Handling topic.

When implementing a handling function, use the object passed to it as its parameter. Among the fields of this object, you can find the series whose selection state has been changed. To identify whether this series was selected or deselected, call its isSelected() method. To discover series fields and methods, refer to the Series class description.

To learn more about how to handle selection, refer to the Selection Handling topic.

The point's tooltip becomes invisible when a user hovers the mouse cursor over another series point. In addition, you can hide a tooltip in code, using the hideTooltip() method of the chart or point.

When a tooltip is made hidden, you can perform specific actions by handling the tooltipHidden event. To do this, implement a handling function and assign it to the onTooltipHidden option. When implementing this function, use the object passed to it as its parameter. Among the fields of this object, you can find the series point whose tooltip becomes hidden.

The point's tooltip appears when a user hovers the mouse cursor over the point. In addition, you can show a tooltip in code, using the showTooltip() method of the chart or point.

When a tooltip appears, you can perform specific actions by handling the tooltipShown event. To do this, implement a handling function and assign it to the onTooltipShown option. When implementing this function, use the object passed to it as its parameter. Among the fields of this object, you can find the series point whose tooltip appears.

Use this property to set a predefined or custom palette. The colors listed in the specified palette will be used to draw chart series, their points, labels and tooltips. If the number of a series is greater than the number of colors in the palette, palette colors are repeated, but slightly modified.

You can override the color of individual series and their points, labels and tooltips by setting the color property of the corresponding object. In addition, you can define a custom palette to use in your charts. To learn how to do this, refer to the Palettes topic.

When using the widget as an ASP.NET MVC Control, you can specify this option using the VizPalette enum. This enum accepts the following values: Default, SoftPastel, HarmonyLight, Pastel, Bright, Soft, Ocean, Vintage, Violet, Carmine, DarkMoon, SoftBlue, DarkViolet and GreenMist.

If you place the widget on a page that uses a tag modifying the path (<base>, <iframe>, etc.), some of the widget elements may get mixed up or disappear. To solve this problem, set the pathModified option to true.

See Also

• DevExpress.viz.refreshPaths()

To set the points to highlight along with the selected point, set the series.point.selectionMode option.

To learn how to select a point, refer to the Selection Handling topic.

When using the widget as an ASP.NET MVC Control, specify this option using the ChartElementSelectionMode enum. This enum accepts the following values: Single and Multiple.

Multiple Point Selection Demo API - Select a Point Demo

When this option is set to true, the widget will be redrawn automatically in case the size of its parent window changes.

Series point labels display series point values. If your chart contains several series with a large number of points in each, point labels may overlap. In this case, specify how the chart must resolve overlapping using the resolveLabelOverlapping option. To hide certain labels, set this option to 'hide'. Labels to be hidden will be determined automatically.

When using the widget as an ASP.NET MVC Control, specify this option using the PolarChartResolveLabelOverlapping enum. This enum accepts the following values: None and Hide.

When this option is set to true, the widget text flows from right to left, and the layout of elements is reversed. To switch the entire application/site to the right-to-left representation, assign true to the rtlEnabled field of the object passed to the DevExpress.config(config) method.

DevExpress.config({
    rtlEnabled: true
});

A series represents a grouping of related data points. The most important characteristic of a series is its type, which determines a particular visual representation of data. You can find more details on each series type in the corresponding topics in the Series help section.

To define a single series, assign an object defining the series to the series configuration object. In the series' object, specify the series type, data source fields, the appearance of the series points and other options.

To show several series, specify series as an array of objects defining series. If you need to set similar values to properties of several series, use the commonSeriesSettings configuration object. It exposes the properties that can be specified for all series at once and for all series of a particular type at once. Note that the values specified for a series individually (in the series array) override the values that are specified for all series (in the commonSeriesSettings object).

To set the series elements to highlight when a series is selected, set the series selectionMode option.

To learn how to select a point, refer to the Selection Handling topic.

When using the widget as an ASP.NET MVC Control, specify this option using the ChartElementSelectionMode enum. This enum accepts the following values: Single and Multiple.

In most cases, you can organize the array that is assigned to the chart's dataSource option in the following way.

[
    {arg: arg1Value, series1Value: val11, series2Value: val12, ...}
    {arg: arg2Value, series1Value: val21, series2Value: val22, ...}
    ...
    {arg: argNValue, series1Value: valN1, series2Value: valN2, ...}
]

Each object that is included in the array represents an argument value and the values of all series for this argument.

However, there are some scenarios in which you do not know exactly how many series will be added. In these cases, you will not be able to define the data source in the manner detailed above. Instead, define it in the following way.

[
    {seriesName: series1, arg: arg11Value, val: value11 }
    {seriesName: series1, arg: arg12Value, val: value12 }
    ...
    {seriesName: seriesM, arg: argM1Value, val: valueM1 }
    {seriesName: seriesM, arg: argM2Value, val: valueM2 }
    ...
]

If you define a data source in this manner, set the argument and value fields using the argumentField and valueField properties of the commonSeriesSettings configuration object (for all series at once). Then, define a template for the series using the seriesTemplate configuration object. Within this object, set the data source field that specifies the series name to the nameField option.

If you need to specify individual values for options of a particular series, assign a callback function to the customizeSeries option of the seriesTemplate object.

The widget occupies its container's entire area by default. Use the size object to specify the widget's size if it should be different from that of its container. Assign 0 to size object's height and width options to hide the widget.

A theme is a widget configuration that gives the widget a distinctive appearance. Use can use one of the predefined themes or create a custom one. Changing the option values in the widget's configuration object overrides the theme's corresponding values.

When using the widget as an ASP.NET MVC Control, specify this option using the VizTheme enum. This enum accepts the following values: GenericLight, GenericDark, GenericContrast, GenericCarmine, GenericDarkMoon, GenericSoftBlue, GenericDarkViolet, GenericGreenMist, Android5Light, IOS7Default, Win10Black and Win10White.

The widget's title is a short text that usually indicates what is visualized. If you need to specify the title's text only, assign it directly to the title option. Otherwise, set this option to an object with the text and other fields specified.

The title can be accompanied by a subtitle elaborating on the visualized subject using the title.subtitle object.

A tooltip is a miniature rectangle displaying values of a series point. A tooltip appears when the end-user hovers the cursor over a series point. You can enable/disable tooltips, change their appearance and format their text using fields of the tooltip configuration object.

In a polar coordinate system, the argument axis is a circle because it tracks a continuous angle change. When the argument in the chart's data source is discrete, you may want to display the argument axis as a discrete axis. For this purpose, set the useSpiderWeb option to true. In this instance, the argument axis, as well as the value axis' grid lines, will be displayed by straight lines between axis ticks/grid lines.

The spider web option is supported in the following series types.

• line
• area
• scatter

View Demo

For charting, the polar coordinate system is used to determine each point uniquely on a plane through two numbers, the argument and the value of the point. A circular and straight lines (the axis of arguments and the axis of values) are specified to define the coordinates. To define the argument axis, use the argumentAxis configuration object. To define the value axis, use the valueAxis configuration object.

To set the properties of all axes to a common value, use the commonAxisSettings configuration object. It exposes properties that can be specified for all axes simultaneously. Note that the value specified for an axis individually (in the argumentAxis or valueAxis object) overrides the value that specified in the commonAxisSettings object.