atomic_ui_kit

A small kit of domain-free Flutter widgets: neumorphic buttons and containers, gradient text, switches, badges, and more. The widgets use only Flutter and decimal. They do not know about app models, state management, or platform plugins.

Widgets

Widget	Description
`NeuButton`	Neumorphic button with an ink splash and an optional gradient.
`NeuContainer`	Neumorphic container that paints the neu shadows.
`NeumorphicCard`	Neumorphic card with padding around its child.
`NeumorphicProgress`	Linear progress bar with the neu shadows.
`NeuTheme`	`ThemeExtension` with the shared neu shadows, background color, and radius.
`AtomicTheme`	`ThemeExtension` with the base color, shadow colors, depth, and radius.
`AtomicTextField`	Inset neumorphic text field with a label, hint, error text, and icons.
`AtomicSegmentedControl`	Animated pill selector with keyboard and semantics support.
`PressableScale`	Scales its child down while pressed.
`AppFlatButton`	Flat button with an ink splash and an optional border.
`GradientText`	Paints text with a `Gradient` through a `ShaderMask`.
`Indicator`	Colored shape followed by a bold label.
`DropdownMenuIcon`	Button that opens an overlay menu and reports the selected item.
`AnimatedListItem`	List item that scales and tilts into place on the first build.
`PercentSwitch`	Row of 25 %, 50 %, 75 %, and MAX options.
`TimeRangeSwitch`	Row of 1Y, 1M, 1W, and 1D options.
`PriceBadge`	Price change badge: green for a positive change, red for a negative change.
`slideUpRoute`	`Route` that slides a page up from the bottom of the screen.

Install

flutter pub add atomic_ui_kit

Usage

MaterialApp(
  theme: ThemeData(
    extensions: const [
      NeuTheme(
        keyBackgroundColor: Color(0xFF252F45),
        borderRadius: 12,
      ),
    ],
  ),
  home: Center(
    child: NeuButton(
      height: 56,
      width: 200,
      onTap: () {},
      child: const Text('Buy'),
    ),
  ),
);

PercentSwitch reports 0.25, 0.5, 0.75, or 1.0. TimeRangeSwitch reports TimeRangeSwitchValue.day, .week, .month, or .year:

PercentSwitch(
  onChanged: (percent) {
    // 0.25, 0.5, 0.75 or 1.0
  },
);

TimeRangeSwitch(
  onChanged: (range) {
    // TimeRangeSwitchValue.day, .week, .month or .year
  },
);

Theming

AtomicTheme carries the shared values of the kit: the base color, the light and dark shadow colors, the depth, and the radius. Register it on the ambient ThemeData:

MaterialApp(
  theme: ThemeData(
    extensions: const [
      AtomicTheme(
        baseColor: Color(0xFF252F45),
        depth: 2,
        radius: 12,
      ),
    ],
  ),
  home: const NeumorphicCard(child: Text('Themed card')),
);

The neumorphic widgets resolve each value in this order: the explicit widget argument, the NeuTheme extension, the AtomicTheme extension, and the built-in defaults. The built-in defaults reproduce the original look of the package.

depth is the shadow offset, and the blur radius is depth * 4. The default depth of 1 reproduces the original shadows exactly. AtomicTheme.of(context) returns the registered extension, or the default values when the app registers none.

AtomicTheme.light() and AtomicTheme.dark() build ready-made palettes. They derive the shadow colors from the base color and use a radius of 16:

MaterialApp(
  theme: ThemeData(
    extensions: <ThemeExtension<dynamic>>[AtomicTheme.dark()],
  ),
  home: const NeumorphicCard(child: Text('Dark preset')),
);

Pass a baseColor, lightShadow, darkShadow, depth, or radius to adjust a preset.

NeumorphicCard

NeumorphicCard paints the neu shadows behind a rounded surface and pads its child:

NeumorphicCard(
  padding: EdgeInsets.all(20),
  child: Text('Card content'),
);

The card reads the ambient theme by default. Pass color, radius, shadows, or depth to override a value.

NeumorphicProgress

NeumorphicProgress shows a fraction between 0.0 and 1.0 as a linear bar:

NeumorphicProgress(
  value: 0.6,
  height: 14,
  color: Colors.green,
);

The bar paints the neu shadows by default and reads the theme. color sets the filled part and trackColor sets the track. The bar announces its percentage value to assistive technologies.

AtomicTextField

AtomicTextField draws a neumorphic inset field. The dark shadow sits at the top left and the light shadow at the bottom right; focus strengthens both:

AtomicTextField(
  label: 'E-mail',
  hint: 'you@example.com',
  prefixIcon: Icon(Icons.mail_outline),
  errorText: 'Enter an e-mail address.',
);

controller, focusNode, maxLines, obscureText, keyboardType, onChanged, and onSubmitted work like their TextField counterparts.

AtomicSegmentedControl

AtomicSegmentedControl shows a row of options with an animated indicator behind the selected one:

AtomicSegmentedControl<String>(
  segments: const [
    AtomicSegment(value: '1D', label: '1D'),
    AtomicSegment(value: '1W', label: '1W'),
    AtomicSegment(value: '1M', label: '1M'),
  ],
  selected: period,
  onChanged: (value) => setState(() => period = value),
);

The control announces each segment with its selected state. Tap a segment, or focus the control and press the left and right arrow keys. Set enabled to false to ignore input.

PressableScale

PressableScale adds a press-down scale to any widget:

PressableScale(
  onPressed: () {},
  child: const NeumorphicCard(child: Text('Tap me')),
);

The wrapper is a gesture target, so wrap content that does not handle taps itself. When the platform asks for reduced motion, the child does not scale.

Platforms

atomic_ui_kit is pure Flutter with no native code and no platform plugins. It runs on Android, iOS, web, macOS, Windows, and Linux.

Example

A runnable app in example/ shows the widgets. It has a components gallery and a trading dashboard.

Screenshots

Widget gallery