mantle_core #

Weave your own widgets. Mantle is a Flutter theming architecture where the theme owns more than colors — it owns the design tokens (and, across the Mantle packages, the structure of every widget).

mantle_core is the runtime foundation: token primitives, MantleTheme, MantleProvider, and root-theme access via the Mantle facade.

Inspired by Mantine. Sister packages (mantle_widgets, mantle_basic, codegen, …) build on this core.

• Gallery: mantle.leslmosnk.com
• Docs: leslmosnk2.github.io/Flutter-Mantle/#/core

Install #

dependencies:
  mantle_core: ^1.1.0

A runnable sample lives in example/.

Quick start #

Provide a theme at the root of your app (above WidgetsApp so overlays still find it):

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

void main() {
  runApp(
    MantleProvider(
      theme: myTheme, // a MantleTheme with your tokens
      child: WidgetsApp(
        color: const Color(0xFF228BE6),
        builder: (context, child) => const HomePage(),
      ),
    ),
  );
}

Read tokens from context (rebuilds when that aspect of the theme changes):

@override
Widget build(BuildContext context) {
  final mantle = MantleTheme.of(context);
  return ColoredBox(
    color: mantle.colors['gray'][0],
    child: Padding(
      padding: mantle.spacing.all('md'),
      child: Text('Hello', style: mantle.typography.body),
    ),
  );
}

Or via the root-theme facade (no BuildContext, no rebuild subscription — fine outside build, or when the root theme is stable):

final color = Mantle.theme.colors['red'][6];

What's included #

License #

MIT. See LICENSE.