datachart-series-highlighting.adoc

Series Highlighting

Topic Overview

Purpose

This topic provides information on enabling the series highlighting feature along with a listing of the supported series. This topic also explains how to configure the series highlighting using the available events.

Required background

The following topic is a prerequisite to understanding this topic:

Topic	Purpose
Getting Started with Data Chart	The {DataChartName} requires a data object model to be mapped to control’s DataContext property. This article will provide a simple data object model but you can create your own and use it with this sample code instead.

In this topic

This topic contains the following sections:

• Series Highlighting

  • Overview

  • Preview

  • Properties

  • Example

• Events

  • Overview

  • Event Arguments Properties

  • Example

• Related Content

Series Highlighting

Overview

This feature allows you to highlight an entire series or individual items within the series. For example, highlights the entire line in a series such as the LineSeries as it is all one shape; however, highlights can be applied to each individual column in a series such as ColumnSeries. Individual markers can be highlighted in all supported series.

Currently the feature only supports highlighting via the mouse.

The series highlighting feature is supported for the following series types:

• Category Series

• Range Category Series

• Financial Series

• Financial Indicators

Preview

The following screenshot is a preview of the xam DataChart control with a ColumnSeries and the series highlighting feature enabled.

Properties

The following table summarizes the properties used for series highlighting. These properties are set on the supported series.

Property Name	Property Type	* Description*
IsHighlightingEnabled	Boolean	Enables the series highlighting feature, by default it is set to False.
HighlightingTransitionDuration	TimeSpan	Determines the duration that the highlighting change takes.

Example

The screenshot, following the table, demonstrates how a chart with the IsHighlightingEnabled and HighlightingTransitionDuration properties of the ColumnSeries looks as a result of the following settings:

Property	Value
IsHighlightingEnabled	True
HighlightingTransitionDuration	00:00:10

Following is the code that implements this example:

Events

Overview

There are two events that are specifically related to the series highlighting feature.

• AssigningCategoryStyle

• AssigningCategoryMarkerStyle (not supported for Financial Series or Financial Indicators)

The series highlighting feature is supported for the following series types:

• Category Series

• Range Category Series

• Financial Series

• Financial Indicators

These events can be configured to achieve the following:

• Modify the way that the highlighting is represented

• Modify the appearance properties assigned to the entire series such as a LineSeries, or each individual item in the series for the series having individual items such as ColumnSeries.

When using the above events to configure the highlighting on the series, only the properties that are available on that particular series can be used. For example, overriding the Fill or RadiusX property of a LineSeries does not have any affect since those properties do not affect the LineSeries.

Event Arguments Properties

The following table summarizes the properties of the AssigningCategoryStyleEventArgsBase.

Property Name	Property Type	* Description*
StartIndex	Int	Start index of the range of data that is currently being highlighted.
EndIndex	Int	End index of the range of the data that is currently being highlighted.
StartDate	DateTime	Start date of the range of data that is currently being highlighted.
EndDate	DateTime	End date of the range of data that is currently being highlighted.
GetItems	GetCategoryItemsEventHandler	Actual items from the data source being highlighted. However, if there is a lot of data and you called it every time the event was fired, will negatively impact performance.
Fill	Brush	Overrides the default Fill property of the series. However, this property only takes affect if the Fill property only affects that particular series.
Stroke	Brush	Overrides the default Stroke property of the series.
Opacity	Double	Overrides the default the Opacity property of the series.
HighlightingInfo	HiglightingInfo	Determine the styling of the highlighted series.
MaxAllSeriesHighlightingProgress	Double	Progress state of the highlighting of the series. Value from 0 to 1.
SumAllSeriesHighlightingProgress	Double	Progress state of the highlighting of the series. Value from 0 to 1.
HighlightingHandled	Bool	When set to True the default highlighting does not apply.
HasDateRange	Bool	Determines the event has a valid date range

The AssigningCategoryMarkerStyleEventArgs inherit all the same properties as the AssigningCategoryStyleEventArgsBase as listed in the table above.

Example

The following screenshot displays an example of using the AssigningCategoryStyle event to change the highlighting feature to fade non highlighting columns instead of changing the highlighting column.

Following is the code implemented for this example:

Related Content

Topics

The following topics provide additional information related to this topic:

Topic	Purpose
Getting Started with Data Chart	The {DataChartName}™ requires a data object model to be mapped to control’s DataContext property. This article will provide a simple data object model but you can create your own and use it with this sample code instead.
Configuring {DataChartName}	This section is your gateway to important conceptual and task-based information that will help you to use the various features and functionalities provided by the {DataChartName}™ control.