Problem with annotation and CategoricalAxis

[Andrew]

Hi, i am creating an annotation dynamically using custom behavior (user set annotation points by clicking on scatter plot). The problem is to bound the annotation to categorical axis. I need to have annotation in any place user wants, not only in one of the CategoricalAxis values (for example in the middle of two categories). Can you help me with some ideas how can i do that?

[Martin Ivanov]

Hello Andriy,

The annotations of the chart are positioned using values presented on the chart axes. This said, you cannot place an annotation between two categories, but only on the concrete category position.

A possible way to achieve your requirement is to place a Canvas panel on top of the chart and manually add Ellipse controls in the panel when necessary. You can use the Conversion API of the chart to convert between screen position and data values. Also, you can get the plot area so you can restrict where the Ellipses can be drawing using the PlotAreaClip property of the chart.

I hope this helps.

Regards, Martin Ivanov
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