DNA • Progressive Web Components

DNA aims to unleash the true power of Custom Elements through a declarative definition API, with builtin elements extension support and a simpler composition mechanism (yes, it does not use ShadowDOM).

DNA simplifies and encourages the use of customized built-in elements, which inherit methods and properties from standard HTML, preserving usability and accessibility features.

DNA offers @property and @state decorators for adding reactivity to a component's class fields, ensuring that any changes are reflected in the component's template. These properties and states can be monitored, synchronized with attributes, and trigger change events.

DNA uses event delegation for listening to events from a component's elements or slotted contents, offering the @listen decorator to streamline the process. Events can be asynchronous and dispatched from the component's class.

DNA uses Quantum instead of ShadowDOM to render slotted children, simplifying the usage of custom elements inside forms and providing a more flexible management of slotted contents. Unlike ShadowDOM, Quantum also works for built-in elements, allowing you to use even inside buttons.

Install via NPM:

npm i @chialab/dna

yarn add @chialab/dna

import { Component, customElement, listen, property } from '@chialab/dna';

@customElement('hello-world')
class HelloWorld extends Component {
    // define an observed property
    @property() name: string = '';

    render() {
        return (
            <>
                <input
                    name="firstName"
                    value={this.name}
                />
                <h1>Hello {this.name || 'World'}!</h1>
            </>
        );
    }

    // delegate an event
    @listen('change', 'input[name="firstName"]')
    private onChange(event: Event, target: HTMLInputElement) {
        this.name = target.value;
    }
}

Then use the element in your HTML:

<hello-world></hello-world>

Install the dependencies and run the build script:

yarn install

yarn build

This will generate the bundles in the dist folder, as well as the declaration files.

Run the test script:

yarn test

DNA is released under the MIT license.