Sets the cell shading fill (foreground) color to one of the 12 Office theme color slots with an optional tint adjustment. Companion of
Interior.Color for callers who want to address Office theme colors directly (so Excel can re-tint the cell with the workbook's theme palette) instead of pinning a fixed RGB. Available since v2.61.0 (chart backlog wave D phase 4).
Syntax
procedure SetThemeColor(ThemeIdx: Word; Tint: Double);
Parameters
ThemeIdx — 0-based theme slot:
0=lt1, 1=dk1, 2=lt2, 3=dk2,
4..9=accent1..accent6, 10=hlink, 11=foHlink.
Matches the standard Office theme order used by the XLSX side.
Tint — spec-style lighter/darker adjustment in the range -1.0 .. +1.0.
0.0 uses the theme slot's base color; negative values darken (HSL luminance toward 0),
positive values lighten (HSL luminance toward 1). The HotXLS reader encodes this as a Q15 signed
integer in the FullColorExt.nTintShade field of the XFExt record.
Remarks
The setter walks two paths so the same cell renders correctly in both Excel 2007+ and Excel 2003:
- Indexed icv on the XF record (legacy) — the theme + tint resolves through the workbook's BIFF theme palette into an RGB, which then picks the closest 56-color palette index. Excel 97-2003 sees this approximation when the file is opened.
- FullColorExt slot on XFExt $087D (Excel 2007+) — the writer emits a rich-color side record with
xclrType=3 (theme), xclrValue=ThemeIdx, and nTintShade derived from Tint. Excel 2007+ uses this to recover the exact theme intent and re-tints the cell whenever the workbook theme palette changes — the same backward-compatibility trick Microsoft uses when "Save As" downgrades a theme-styled .xlsx to .xls.
Cells set via
SetThemeColor round-trip on load:
Interior.Color returns the resolved RGB (theme + tint applied through the BIFF theme palette) so callers always see a concrete LongWord value.
Custom theme palettes set in Excel via Page Layout → Colors survive load and save through the BIFF8 Theme ($0892) record, so any caller-side SetThemeColor reference resolves through the workbook's actual theme rather than the default Office scheme.
Example
Fills the header row with accent1 and tags warning cells with a 50% lightened red accent (accent2 + 0.5 tint).
var
Header : IXLSRange;
Warnings : IXLSRange;
begin
Header := Workbook.Sheets[1].Range['A1', 'G1'];
Header.Interior.SetThemeColor(4, 0.0); // accent1, base shade
Warnings := Workbook.Sheets[1].Range['G2', 'G20'];
Warnings.Interior.SetThemeColor(5, 0.5); // accent2, 50% lighter
Workbook.SaveAs('ThemeFills.xls', xlExcel97);
end;
See also