The grid moves up/down with the arrow keys, when there is no cell opened for edit. When such is opened, the editor will handle the keyboard (if needed), so the spinner or the date time picker can change their values.
Please refer to the following post of mine, where I have provided an example how to prevent value change of the spin editor with the arrow keys, and move the row selection instead: http://www.telerik.com/forums/gridviewdecimalcolumn-up-down-key#yaJobaxmWEyB16Qaub1Zww
I hope that you find this information useful. Should you have any other questions, do not hesitate to contact us.
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