Material Design 3 Only #

A comprehensive toolkit for implementing Material Design 3 in Flutter. Build beautiful and consistent UIs aligned with official metrics and guidelines using a powerful set of design tokens and ready-to-use helper widgets.

This package encapsulates the Material 3 guidelines into easy-to-use tokens, allowing you to focus on your app logic while maintaining visual fidelity.

Installation #

Add this line to your project's pubspec.yaml file:

dependencies:
  material_design: ^0.6.2

Then run flutter pub get.

Usage #

Import the package to start using the tokens:

import 'package:material_design/material_design.dart';

Core Tokens #

This package provides a comprehensive set of Material 3 design tokens, allowing you to build consistent and beautiful UIs.

Color #

The color system is based on a seed color, which generates a full ColorScheme for both light and dark modes.

• ColorScheme.fromSeed({seedColor, brightness}): Generates a full M3 color scheme.

Example:

MaterialApp(
  theme: ThemeData(
    useMaterial3: true,
    colorScheme: ColorScheme.fromSeed(
      seedColor: Colors.blue,
      brightness: Brightness.light,
    ),
  ),
  darkTheme: ThemeData(
    useMaterial3: true,
    colorScheme: ColorScheme.fromSeed(
      seedColor: Colors.blue,
      brightness: Brightness.dark,
    ),
  ),
)

• M3TonalColor.fromElevation(context, elevation): Calculates the surface color with an elevation-based tint, crucial for M3's tonal elevation.

Example:

Container(
  color: M3TonalColor.fromElevation(context, M3Elevation.level2),
)

Typography #

The full M3 type scale is available via the M3TypeScale class.

• M3TypeScale: Provides 15 TextStyle tokens, from displayLarge to labelSmall.

Example:

MaterialApp(
  theme: ThemeData(
    useMaterial3: true,
    textTheme: TextTheme(
      displayLarge: M3TypeScale.displayLarge,
      displayMedium: M3TypeScale.displayMedium,
      displaySmall: M3TypeScale.displaySmall,
      ...
    ),
  ),
)

final textTheme = Theme.of(context).textTheme;
Text(
  'Display Large',
  style: textTheme.displayLarge,
)

Shape & Corner Radius #

Apply shapes and rounded corners to your widgets using a three-tiered token system: M3Shape, M3BorderRadius, and M3Radius. This structure provides everything from ready-to-use RoundedRectangleBorder objects to raw Radius values for advanced customizations.

M3Shape (High-Level) #

Use M3Shape for the most direct application of shapes. This class provides pre-defined RoundedRectangleBorder objects that can be used directly in the shape property of widgets like Card, Material, or ShapeDecoration.

Available tokens: none, extraSmall, small, medium, large, largeIncreased, extraLarge, extraLargeIncreased, extraExtraLarge, and full (StadiumBorder).

When to use: This is the ideal choice in most cases, whenever you need to apply a standard Material 3 shape to a widget.

Example:

Dart

Container(
  decoration: ShapeDecoration(
    shape: M3Shape.large, // 16dp circular RoundedRectangleBorder
  ),
)

M3BorderRadius (Mid-Level) #

Use M3BorderRadius when you need a BorderRadius object to apply the same radius to all corners. It's perfect for the borderRadius property of a BoxDecoration or for clipping widgets like ClipRRect.

When to use: In a BoxDecoration or to control the rounding of an InkWell splash effect or a ClipRRect.

Example:

Dart

Container(
  decoration: BoxDecoration(
    borderRadius: M3BorderRadius.large, // 16dp circular BorderRadius
  ),
)

M3Radius (Low-Level) #

M3Radius provides the raw Radius values. Use this class for custom scenarios where you need to define different radii for specific corners of a widget.

When to use: For creating complex or asymmetrical shapes using BorderRadius.only() or BorderRadius.vertical()/horizontal().

Example:

Dart

Container(
  decoration: BoxDecoration(
    borderRadius: BorderRadius.only(
      topLeft: M3Radius.extraLarge, // 28dp circular Radius
      bottomRight: M3Radius.extraLarge, // 28dp circular Radius
    ),
  ),
)

Summary: Which One to Use? #

Elevation #

Use elevation tokens for surface depth and shadow tokens for casting shadows.

• M3Elevation: Defines 6 elevation levels from level0 (0dp) to level5 (12dp).
• M3Shadow: Provides BoxShadow lists for each elevation level (level0 to level5).

Example:

final useShadow = true;
final elevation = M3Elevation.level5;
final elevationSurfaceColor = M3TonalColor.fromElevation(context, elevation);
final elevationShadows = useShadow ? M3Shadow.fromElevation(elevation) : <BoxShadow>[];
Container(
  decoration: ShapeDecoration(
    shape: M3Shape.small,
    color: elevationSurfaceColor,
    shadows: elevationShadows,
  ),
),

Spacing & Layout #

A granular scale for consistent spacing, margins, and layouts.

• M3Spacing: Provides spacing values from none to space128 based on a 4dp grid. Ideal for padding and small gaps between UI elements.

Example:

Padding(
  padding: const EdgeInsets.all(M3Spacing.space16), // 16dp padding
  child: Text('Hello, Material!'),
)

• M3Margin: Provides semantic margin values for the outer edges of the screen layout.

  • screen (16dp) for compact/medium screens.

  • screenLarge (24dp) for large/extra-large screens.

Example:

Container(
  margin: const EdgeInsets.symmetric(horizontal: M3Margin.screen),
  child: Text('Content with screen margins'),
)

• M3Spacer: pane (24dp) for the gap between two content panes.

  • screen (16dp) for compact/medium screens.

  • screenLarge (24dp) for large/extra-large screens.

Example:

Row(
  children: [
    Expanded(child: ContentPane1()),
    const SizedBox(width: M3Spacer.pane),
    Expanded(child: ContentPane2()),
  ],
)

Density #

Adjust component density for different interaction models.

• M3Density: An enum with comfortable (default) and compact values.

Example:

// Use a switch to toggle between density settings
final density = isCompact ? M3Density.compact : M3Density.comfortable;

// This could be used to adjust layout constraints
final horizontalPadding = density == M3Density.compact
    ? M3Spacing.space8
    : M3Spacing.space16;

Motion #

Standardized duration and easing curves for animations.

• M3MotionDuration: Provides duration values from short1 to extralong4.
• M3MotionEasing: Provides duration values from emphasizedAccelerate to standardDecelerate.

Example:

AnimatedContainer(
  duration: M3MotionDuration.long2,
  curve: M3MotionEasing.emphasizedAccelerate,
  // ...
)

Other Tokens #

The library also includes tokens for various other UI properties.

• M3Border: Standard border widths.

  • thin (1dp)

  Example:

  Container(
    decoration: BoxDecoration(
      border: Border.all(width: M3Border.thin),
    ),
  )
  

• M3StateLayerOpacity: Opacity values for states and elements.

  • hover (0.08), focus (0.10), pressed (0.10), dragged (0.16)
  • disabledContent (0.38), disabledContainer (0.12)

  Example:

// Apply a state layer overlay for interaction feedback
final isPressed = true;
final stateLayerOpacity = isPressed ? M3StateLayerOpacity.pressed : 0.0;

Stack(
  children: [
    // Main widget content
     Positioned.fill(
      child: AnimatedContainer(
        duration: M3MotionDuration.short3,
        decoration: BoxDecoration(
          color: Theme.of(context).colorScheme.primary.withOpacity(stateLayerOpacity),
        ),
      ),
    ),
  ],
)

• M3Breakpoint: Breakpoints for responsive layouts.

• compact (0), medium (600), expanded (840), large (1200), extraLarge (1600)

Example:

final screenWidth = MediaQuery.of(context).size.width;
if (screenWidth >= M3Breakpoint.medium) {
  // Use a two-column layout
}

• M3IconSize: Standard icon size.

  • standard (24dp)

  Example:

  Icon(
    Icons.favorite,
    size: M3IconSize.standard,
  )
  

• M3ZIndex: Conventional z-index values for layering.

  • content (1), floating (10), drawer (100), modal (1000), snackbar (2000), tooltip (9999)

  Example:

  Stack(
    children: [
      Positioned(
        zIndex: M3ZIndex.content,
        child: Text('Content'),
      ),
      Positioned(
        zIndex: M3ZIndex.floating,
        child: FloatingActionButton(onPressed: () {}),
      ),
    ],
  )
  

Example App #

The included example app serves as a complete visual style guide, showcasing all tokens available in this package. Explore it to see the tokens in action.

More content #

https://flutterweb-wasm.web.app/