As per this documentation article:
you can use the
TKCalendarDelegate protocol and implement its calendar:upateVisualsForCell: method to change the styles of a cell depending on its state.
In this method you have a reference to the cell in question which exposes API to help you understand if it is selected or not. Take a look at the API ref:
Based on that state you can use the style
property to change the shape which is exposed by the shape
I hope this is helpful.
Telerik by Progress
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