Theme

DEFAULT_THEME_COLOR_SCHEME

_const

The Office default colour scheme, matching the theme part the writer emits for a workbook with none.

const DEFAULT_THEME_COLOR_SCHEME: Readonly<Record<"accent1" | "accent2" | "accent3" | "accent4" | "accent5" | "accent6" | "dk1" | "dk2" | "folHlink" | "hlink" | "lt1" | "lt2", string>>

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DEFAULT_THEME_FONTS

_const

The Office default typefaces, matching the theme part the writer emits for a workbook with none.

const DEFAULT_THEME_FONTS: ThemeFontScheme

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isThemeColorSlot

_function

Narrow a raw <a:clrScheme> child name to a known ThemeColorSlot.

function isThemeColorSlot(value: string): value is ThemeColorSlot;

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THEME_COLOR_SLOTS

_const

The twelve colour-scheme slots in the order a theme="n" attribute indexes them.

This order is not the order the slots appear in the theme part. ISO/IEC 29500 §20.1.6.2 documents the <a:clrScheme> child sequence as dk1, lt1, dk2, lt2, accent1…6, hlink, folHlink, and that is how the XML is written. But SpreadsheetML's theme="n" does not index that sequence: Excel swaps each dark/light pair: index 0 is lt1, 1 is dk1, 2 is lt2, 3 is dk2.

Verified against Excel Desktop rather than inferred, because the two orders differ only in the first four entries and reading either one into the other silently inverts text against background. See docs/knowledge/specs/theme-color-index-order.md and the recorded observation in test/corpus/fixtures/excel-oracle/theme-color-index-order.json. The stylesheet's own default font is the everyday witness: it carries <color theme="1"/> and renders black, which is dk1.

const THEME_COLOR_SLOTS: readonly ["lt1", "dk1", "lt2", "dk2", "accent1", "accent2", "accent3", "accent4", "accent5", "accent6", "hlink", "folHlink"]

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ThemeColorScheme

_type

A theme's colour scheme: each slot's colour as a 6-hex RRGGBB string. Partial because a foreign theme is free to omit a slot (or express one in a colour model this reader does not decode), and an absent slot is honestly absent rather than silently substituted.

type ThemeColorScheme = Readonly<Partial<Record<ThemeColorSlot, string>>>;

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ThemeColorSlot

_type

One slot of a theme's colour scheme.

type ThemeColorSlot = (typeof THEME_COLOR_SLOTS)[number];

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ThemeFontScheme

_interface

The two typefaces a theme nominates: the major face headings use and the minor face body text uses. A cell's font reaches them by scheme="major"/scheme="minor" instead of naming a typeface, so changing these restyles every such cell at once.

interface ThemeFontScheme {
  readonly major?: string | undefined;
  readonly minor?: string | undefined;
}

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ThemeOverrides

_interface

What a caller can author on a workbook's theme: any subset of the colour slots and typefaces.

interface ThemeOverrides {
  readonly colors?: Readonly<Partial<Record<ThemeColorSlot, string>>> | undefined;
  readonly fonts?: ThemeFontScheme | undefined;
}