I am not entirely sure what kind of data you have bound to your column. That is why I attached a sample project that demonstrates a common scenario with RadGridView. In general if you have a string property bound to the GridViewDataColumn, your default CellEditTemplate should be TextBox and the CellTemplate a TextBlock. For more information about RadGridView you can refer to our documentation, online demos and sdk examples:
1) Getting Started documentation article.
2) Online Demos.
3) SDK Examples - Although GitHub is a very well-known platform we saw a better and easier approach for reviewing our examples by developing our SDK Samples Browser.
I hope this helps.
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