useTheme @astryx-svelte/core v0.3.0 · theme
Usage
Programmatic access to theme tokens for non-CSS consumers like SVG, canvas, Vega, D3, maps, or chart libraries that need values in JavaScript instead of CSS custom property references.ts
Best practices
| Guidance | Practices |
|---|---|
| Do | Use tokens or token(name) when integrating theme colors into SVG attributes, canvas drawing, chart options, or other non-CSS configuration objects inside React components. |
| Do | Use resolveThemeTokens(theme, {mode}) for the same token resolution outside React hooks. |
| Do | Prefer CSS variables or StyleX tokens for ordinary component styling; use this hook only when JavaScript needs token values. |
| Do | Use data visualization tokens such as --color-data-categorical-blue for chart series instead of arbitrary UI colors. |
| Don't | Hardcode light/dark colors in data visualizations: resolve them through the current theme instead. |
| Don't | Assume the hook reflects every CSS cascade override. It resolves tokens for the current Theme mode; local media-surface overrides and arbitrary external CSS may not be represented. |
Returns
| Field | Type | Default | Description |
|---|---|---|---|
name | string | — | Name of the nearest theme, or default when no provider is present. |
mode | 'dark' | 'light' | — | Resolved effective color mode. system mode is resolved to light or dark. |
token | (name: string) => string | — | Resolve a single design token to its current CSS value for the effective mode. |
tokens | Record<string, string> | — | All tokens resolved for the current mode, including defaults and theme overrides. Stable until the active theme or mode changes; uses the same resolution logic as resolveThemeTokens(theme, {mode}). |
Examples
Common configurations, variations, and states.useTheme — Token Values
Read resolved theme token values with useTheme for non-CSS consumers like SVG charts.