Data Item selection will limit one series to be selected across the chart, unless you set use one with that includes series in the name. eg. PerSeriesAndDataItemMultiSelect
. This has no restraints.
Other selection modes offer various methods of selection. For example using SelectionBehavior with PerDataItemMultiSelect will select all series in entire category when multiple series are present, but only one category at a time, deselecting anything selected previously.
You would use "PerDataItemSingleSelect" selection when your series are bound to the same data source and you want to select all items in a record in that datasource. For example if the records in the datasource have fields label, value1, value2 and series 1 is bound to value1 and series 2 is bound to value2 then selecting a point on either series would select values from both series.
The following is a code example that implements multiple selection across all data items and series:
<ig:XamDataChart x:Name="Chart" SelectionMode="SelectionColorFill" SelectionBehavior="PerSeriesAndDataItemMultiSelect">
<ig:XamDataChart.Series>
<ig:ColumnSeries ValueMemberPath="Coal"
</ig:ColumnSeries>
<ig:ColumnSeries ValueMemberPath="Gas"
</ig:ColumnSeries>
</ig:XamDataChart.Series>
</ig:XamDataChart>
var chart = new XamDataChart();
chart.SelectionMode = SeriesSelectionMode.SelectionColorFill;
chart.SelectionBehavior = SeriesSelectionBehavior.PerSeriesAndDataItemMultiSelect;