Flattery is a library for building HTML elements using Widgets.

Widgets are just Dart objects whose purpose is to represent some user interface element. They are implemented using the awesome dart:html package, and do not try to hide it - so you can use your HTML/CSS knowledge to enhance existing widgets, and to create your own, type safely.


A simple usage example:

import 'dart:html' hide Text;

import 'package:flattery/flattery_widgets.dart';

/// Simple Counter Model.
class Counter {
  int value = 0;

/// A Counter Widget.
/// By implementing [ShadowWidget], we make our widget use a shadow root
/// to isolate its contents.
class CounterView extends Counter with Widget, ShadowWidget {
  final text = Text('')..style.textAlign = 'left';

  /// Build the component's Element.
  /// Uses a 2x2 grid to place the child Widgets
  Element build() => Grid(columnGap: '10px', classes: [
      ], children: [
        [text, text],
        // row 1 (repeat the element so it takes up both columns)
          // row 2 contains 2 buttons to inc/decrement the counter
          Button(text: 'Increment', onClick: (e) => value++),
          Button(text: 'Decrement', onClick: (e) => value--),
        // row 2

  CounterView() {
    stylesheet = '* { font-family: sans-serif; }'
        'button { height: 4em; }'
        '.main-grid { width: 25em; }';

  /// All model's setters that affect the state of the view need to be
  /// overridden in the Widget extending it, so that they update the view.
  set value(int value) {
    super.value = value;

  _update() => text.text = 'The current count is $value';


pub get

Run the example

webdev serve example

Running the tests

Unit tests:

pub run test

Use option -r json or r -expanded to see details.

Browser tests:

pub run test -p chrome

Features and bugs

Please file feature requests and bugs at the issue tracker.

Dart Test Documentation:



Flattery is a library for building HTML elements using Widgets. [...]
Extension of main flattery library that exposes several useful widgets to make it easier to implement web applications.