I am glad that the suggested solution was helpful for your case.
As to the provided code snippet, it seems that you are applying a specific format to the column which is expected to affect the displayed text, not the editor indication. Please have in mind that all cells in RadGridView are displayed with plain text when they are not being edited. Once you activate the editor, the respective element for editing the value will be displayed.
Since RadGridView uses data virtualization, all cell elements are created only for the currently visible cells and they are being reused during operations like scrolling, filtering, etc. Displaying only the cell's text is purposed to improve the performance compared to the case with individual style for each column.
Feel free to adopt the suggested solution in order to get the desired editor's indication.
Should you have further questions please let me know.
Dess | Tech Support Engineer, Sr.
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