Yako Celebrations

Full-screen celebrations for Flutter in one line: flames, spinning coins, confetti, fireworks, your own logo popping up everywhere, a slamming title, flash, shake, sound and haptics.

  

_{Classic  CelebrationTier.legendary   ·   Lottie  CelebrationTier.lottieLegendary}

• One line. YakoCelebration.show(context, tier: CelebrationTier.epic). It covers the screen, plays its sound and haptics, and cleans up after itself.
• Ten ready-made tiers in two styles. Five sizes drawn in code, and five built from designer-made Lottie animations.
• Your brand. Your icon pops up in the show and your name sits in a small badge.
• Sound and haptics in time with the picture. The built-in sounds are synthesised by the package's own script, so you can ship them in any app.
• Build your own from 14 effects, each on the same clock.
• Never in the way. It ignores touches, respects reduced motion, and one clock means slow motion and widget tests just work.

Installing

dependencies:
  yako_celebrations: ^1.0.0

Quick start

import 'package:yako_celebrations/yako_celebrations.dart';

YakoCelebration.show(context, tier: CelebrationTier.epic);

That's it: the celebration covers the whole screen, plays its sound and haptics, and cleans up after itself. It sits over everything in the root Overlay; to keep one inside a part of your screen, see Inside one part of the screen.

Change the text, or keep a handle to change it while it runs:

final handle = YakoCelebration.show(
  context,
  tier: CelebrationTier.legendary,
  title: 'Level 10!',
  subtitle: 'NEW RECORD',
  onComplete: () => print('done'),
);

handle.updateSubtitle('+2,500 XP');
handle.cancel(); // stop early

Tiers

Classic tiers

Drawn in code: particles, glows and flames painted every frame.

Tier	Length	What happens
subtle	1.2 s	A quick sparkle and a small chime. For "saved", "done".
nice	2.2 s	Title pop, a burst of confetti, sparkles.
great	3.4 s	Title slam, light rays, confetti cannons, streamers, a few brand pops.
epic	5 s	Flames, coins, fireworks, a storm of brand pops, flash and shake.
legendary	7.5 s	Rainbow flames, a wall of fire, giant brand pops, fireworks, big flash and shake.

Each tier is longer and bigger than the one below it, and each has its own sound, as long as the celebration itself.

Lottie tiers

The same five sizes, built from Lottie animations (light rays, confetti, streamers, fireworks, a coin rain, fire) with a gold title that slams in and catches a light sweep:

Tier	Length	What happens
lottieSubtle	2.4 s	Light rays and a confetti pop, a soft indigo flash.
lottieNice	3 s	Turning violet rays, streamers, a firework cluster.
lottieGreat	3.6 s	Gold title, confetti and fireworks.
lottieEpic	5.2 s	Fire from below, a coin rain, fireworks, warm flash and shake.
lottieLegendary	8 s	A wall of flames, coins in both corners, fireworks everywhere.

YakoCelebration.show(context, tier: CelebrationTier.lottieEpic);

Lottie files take a moment to parse, so load them once at start-up:

YakoCelebration.preload(CelebrationTier.lottieValues);

The Lottie files are free animations from LottieFiles under the Lottie Simple License, not MIT: see assets/lottie/LICENSE.md.

Your brand

Give the package your name and icon once. The icon pops up in the brand-pop effect, alongside the flames and coins; the name shows in a small badge on the bigger tiers.

void main() {
  YakoCelebration.configure(
    brand: CelebrationBrand(
      name: 'MyApp',
      image: const AssetImage('assets/logo.png'), // or icon: MyLogo()
    ),
  );
  runApp(const MyApp());
}

The package ships no icon of its own: use a PNG from your assets as above, or any widget. For an SVG, add flutter_svg to your app and pass icon: SvgPicture.asset('assets/logo.svg').

Pass brand: to show to use another one for a single call. Without a brand, a neutral star pops up instead. A square icon with a transparent background looks best.

Build your own

A tier is just a CelebrationConfig. Start from a preset...

final streak = CelebrationTier.custom(
  CelebrationTier.epic.config.copyWith(
    title: 'STREAK!',
    color: Colors.pinkAccent,
    duration: const Duration(seconds: 4),
  ),
);
YakoCelebration.show(context, tier: streak);

...or from scratch:

final levelUp = CelebrationTier.custom(
  CelebrationConfig(
    duration: const Duration(seconds: 4),
    title: 'Level up!',
    subtitle: '+1 skill point',
    color: Colors.teal,
    backgroundDim: 0.4,
    effects: const [
      TitleSlamEffect(slamFrom: 2.4),
      LightRaysEffect(),
      ConfettiEffect(count: 150, launch: ConfettiLaunch.cannons),
      CoinsEffect(count: 40, start: 0.1, end: 0.8),
      FireworksEffect(shells: 3, area: CelebrationArea.topBand),
      FlashEffect(strength: 0.5, start: 0.03, end: 0.12),
      ShakeEffect(strength: 10, start: 0.03, end: 0.2),
    ],
    sound: const CelebrationSound.builtIn(CelebrationTier.epic),
    haptics: const CelebrationHaptics([
      HapticPulse(0.05, CelebrationHapticKind.heavy),
    ]),
  ),
);

start and end are fractions of the whole length, so a tweaked duration keeps everything in step. Handy helpers: config.without<ShakeEffect>(), config.withEffects([...]).

Effect	What it draws	Main options
TitleSlamEffect	Title slamming in with a bounce, plus the subtitle	slamFrom, fontSize, style, alignment, colors, glow, shimmer
FlamesEffect	Little flames bursting out and drifting	count, size, area (burst, fountain, shower, drift)
CoinsEffect	Spinning gold coins raining down	count, size, area
ConfettiEffect	Fluttering paper confetti	count, size, launch (cannons, burst, rain)
StreamersEffect	Long curly ribbons	count, size, launch
FireworksEffect	Shells rising and bursting	shells, sparks, size, area
SparklesEffect	Twinkling stars	count, size, area
LightRaysEffect	Turning beams behind the title	rays, spin, opacity
BrandPopEffect	Your icon popping up in a staggered storm	count, minSize, maxSize, glow
FireWallEffect	Big animated flames along the bottom	height, tongues, embers
FlashEffect	A full-screen camera flash	strength, color
ShakeEffect	Screen shake	strength, frequency
EdgeGlowEffect	A pulsing glow around the edges	strength, pulse
LottieEffect	A bundled Lottie animation, or your own with LottieEffect.asset	anchor, scale, loop, tint, spinTurns, fadeBottom

Every effect takes a palette: CelebrationPalette.gold, .fire, .party, .rainbow (hue-shifting over time), .accent (shades of the config's color) or your own list of colours.

Your own layers

Your own Lottie file joins like any effect:

LottieEffect.asset('assets/trophy.json',
    anchor: LottieAnchor.center, scale: 0.6, loop: false, start: 0.1)

Any other widget can join on the same clock:

CelebrationConfig(
  extraLayers: [
    (context, progress) => MyWidget(progress: progress),
  ],
)

progress runs from 0 to 1 and follows slow motion and cancelling like every built-in effect.

Sound

Every tier plays its own built-in sound. Change it per call, per tier, or turn it off:

// Just this once.
YakoCelebration.show(context,
    tier: CelebrationTier.epic,
    sound: const CelebrationSound.asset('assets/sounds/win.mp3'));

// App-wide, per tier, and a global mute.
YakoCelebration.configure(
  sounds: const {
    CelebrationTier.legendary: CelebrationSound.url('https://example.com/win.mp3'),
    CelebrationTier.subtle: CelebrationSound.none(),
  },
);
YakoCelebration.muted = true;

Sources: CelebrationSound.builtIn(tier), .asset(path), .file(path), .url(url), .none().

• Sounds play through audioplayers and are preloaded by configure, so the first celebration starts instantly.
• By default the package sets an iOS audio session that mixes with the user's music and respects the silent switch, and takes no audio focus on Android. If your app configures audioplayers itself, pass manageAudioSession: false.
• Have your own audio stack? Pass onPlaySound and the package hands you the sound instead of playing it. Built-in sounds are package assets: (sound as BuiltInCelebrationSound).assetKey.

Haptics

Each tier has a haptic pattern on the celebration's clock (heavy thump on the title hit, lighter taps on each firework...). It uses Flutter's own HapticFeedback, no plugin. Turn it off with YakoCelebration.hapticsEnabled = false.

Shake your app

The title always shakes on the hit. To shake your whole app too, wrap it once:

MaterialApp(
  builder: (context, child) => CelebrationShaker(child: child!),
);

Only the paint position moves; layout and touches keep working.

Inside one part of the screen

show uses the root overlay. To keep a celebration inside a widget (and shake just that widget), use a controller:

final controller = CelebrationController();

CelebrationOverlay(
  controller: controller,
  child: GameBoard(),
);

controller.celebrate(tier: CelebrationTier.great, subtitle: 'Combo x3');

Previews

CelebrationPreview draws any moment of a celebration without playing it: great for a settings screen, a scrubber, or screenshots.

CelebrationPreview(
  tier: CelebrationTier.legendary,
  progress: const AlwaysStoppedAnimation(0.3),
)

Accessibility and performance

• When the user asks for reduced motion (MediaQuery.disableAnimations), a short, calm version plays instead: no flash, no shake, nothing flying; the title fades in. Set your own with CelebrationConfig.reducedMotion.
• The title is announced to screen readers.
• Everything runs off one AnimationController, so timeDilation slows it all down together.
• Particles are pure functions of time with prebuilt paints, paths and colour tables; each layer sits in its own RepaintBoundary.

Example

The example app has a gallery of every tier in both styles, a playground to build your own (effects, length, colours, brand, sound, scrubbing), a 0.25× speed button and a mute button.

Check out other Yako packages:

Badges

Settings UI

Status Alert

Full Screen Menu

Diagonal decoration

Theme Switch

and more to come!