Context extensions

Convenience accessors for ThemeData on BuildContext, defined in extensions.dart as the ThemeContext extension.

How the theme flows

Provider
  └── Theme (InheritedWidget)     ← propagates ThemeData
        └── DefaultTextStyle              ← set to typography.defaultStyle
              └── SnackbarHandler ← overlay for snackbar
                    └── child

ThemeData aggregates six sub-objects: colorScheme, typography, motion, shadows, breakpoints, iconography. Components read them via the BuildContext extensions below rather than calling Theme.of(context) directly.

ThemeContext getters

Getter	Type	Equivalent to
theme	ThemeData	Theme.of(this) — the full theme from the nearest Theme ancestor.
colorScheme	ColorScheme	theme.colorScheme
typography	Typography	theme.typography
motion	Motion	theme.motion
shadows	Shadows	theme.shadows
breakpoints	Breakpoints	theme.breakpoints
iconography	Iconography	theme.iconography

Usage inside a component:

import 'package:catalyst_ui/catalyst_ui.dart';
import 'package:flutter/widgets.dart';

Widget build(BuildContext context) {
  return DecoratedBox(
    decoration: BoxDecoration(
      color: context.colorScheme.surface,
      borderRadius: Radii.mdAll,
      boxShadow: context.shadows.sm,
    ),
    child: Text(
      'Hello',
      style: context.typography.body,
    ),
  );
}

Every built-in component reads styling exclusively through these getters — never hardcoding colours, fonts, durations, breakpoint values, or icon data — so overriding any ThemeData sub-object (see ColorScheme, Typography, Motion, Shadows, and Tokens) propagates automatically to every component beneath the Theme in the tree.

BrightnessFilter extension

extensions.dart also defines a BrightnessFilter extension on Widget:

Method	Type	Description
withBrightness(double amount)	Widget	Applies a multiplicative brightness factor via a colour-matrix filter. 1.0 leaves the widget unchanged; values below 1.0 darken it — used for pressed/active feedback on interactive elements.

MyIcon().withBrightness(0.85) // dims the widget for a pressed state

This extension is unrelated to ThemeData — it operates directly on any Widget and does not require a BuildContext or an ambient Theme.