Firing a Click event on a navigation button of a SplitterElement involves calling a complex logic considering the collapsing and the expanding of panels, their direction and state.
On a more general level I understand that you need to programmatically collapse or expand a SplitPanel. You can easily achieve this task by setting the value of the Collpased property of the SplitPanel. Please see my code snippet below:
I am also sending you a gif file showing the result on my end.
I hope this helps. Should you have further questions please do not hesitate to write back.
Regards,
Hristo Merdjanov
Telerik
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