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NullReferenceException When Using TypePath of CategoricalSeriesDescriptor


Product Version 2019.2.510
Product Progress® Telerik® UI for WPF


Null Reference Exception occurs when TypePath of RadCartesianChart series descriptor is set.

This reproduces only if the Telerik.Windows.Controls.Charting dll is referenced.


This happens when the TypePath property points to a value that holds a type of Telerik.Windows.Controls.Charting.LineSeries (or any other series type), instead of Telerik.Windows.Controls.Chart.LineSeries as expected by the descriptor.

To resolve this use one of the following two solutions.

  • When setting the type of the series, use also its namespace or add a using directive that points to Telerik.Windows.Controls.ChartView namespace.

  • Or remove the reference to the Telerik.Windows.Controls.Charting dll. It hosts the old RadChart controls.

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