preact-material-components
Version:
preact wrapper for "Material Components for the web"
82 lines (67 loc) • 2.33 kB
JavaScript
import { FORCE_RENDER } from './constants';
import { extend } from './util';
import { renderComponent } from './vdom/component';
import { enqueueRender } from './render-queue';
/** Base Component class.
* Provides `setState()` and `forceUpdate()`, which trigger rendering.
* @public
*
* @example
* class MyFoo extends Component {
* render(props, state) {
* return <div />;
* }
* }
*/
export function Component(props, context) {
this._dirty = true;
/** @public
* @type {object}
*/
this.context = context;
/** @public
* @type {object}
*/
this.props = props;
/** @public
* @type {object}
*/
this.state = this.state || {};
}
extend(Component.prototype, {
/** Returns a `boolean` indicating if the component should re-render when receiving the given `props` and `state`.
* @param {object} nextProps
* @param {object} nextState
* @param {object} nextContext
* @returns {Boolean} should the component re-render
* @name shouldComponentUpdate
* @function
*/
/** Update component state by copying properties from `state` to `this.state`.
* @param {object} state A hash of state properties to update with new values
* @param {function} callback A function to be called once component state is updated
*/
setState(state, callback) {
let s = this.state;
if (!this.prevState) this.prevState = extend({}, s);
extend(s, typeof state==='function' ? state(s, this.props) : state);
if (callback) (this._renderCallbacks = (this._renderCallbacks || [])).push(callback);
enqueueRender(this);
},
/** Immediately perform a synchronous re-render of the component.
* @param {function} callback A function to be called after component is re-rendered.
* @private
*/
forceUpdate(callback) {
if (callback) (this._renderCallbacks = (this._renderCallbacks || [])).push(callback);
renderComponent(this, FORCE_RENDER);
},
/** Accepts `props` and `state`, and returns a new Virtual DOM tree to build.
* Virtual DOM is generally constructed via [JSX](http://jasonformat.com/wtf-is-jsx).
* @param {object} props Props (eg: JSX attributes) received from parent element/component
* @param {object} state The component's current state
* @param {object} context Context object (if a parent component has provided context)
* @returns VNode
*/
render() {}
});