Is it possible to show a custom tool tip when the focus is in the cell, as the user navigates through a grid using the keyboard using the tab key?
The code posted here probably won't work, since the tooltip won't show up unless the mouse hovers over a cell.
If you want to force a tooltip to show up based on the current active cell, then you could use the UltraToolTipManager component and call the ShowToolTip method in the AfterCellActivate event of the grid.