I'm trying to add a background to a cell that I'm exporting from a XamDataGrid to Excel.

In the CellExporting event, I'm conditionally applying a formula, then setting the fill.

This works fine for cells without a formula, however, the color is not showing on cells that contain formulas. What do I need to change?

private void grid_CellExporting (object sender, CellExportingEventArgs e)
{
var cell = e.CurrentWorksheet.Rows[e.CurrentRowIndex].Cells[e.CurrentColumnIndex];

...

if (hasFormula)
{
cell.ApplyFormula(formula);
}
...

e.FormatSettings.FillPatternBackgroundColor = Color.Yellow;
e.FormatSettings.FillPatternForegroundColor = Color.Yellow;
e.FormatSettings.FillPattern = FillPatternStyle.Solid;
}