PendingStateController

Examples

Description #

The PendingStateController is a class that helps manage the pending state of a reactive element. It provides a standardized way to indicate when an element is in a pending state, such as during an asynchronous operation. When the components is in a pending state it supplies the pending state UI sp-progress-circle which gets rendered in the component. It also updates the value of ARIA label of the host element to its pending-label based on the pending state.

The HostWithPendingState interface defines the properties that a host element must implement to work with the PendingStateController.

Usage #

See it on NPM! How big is this package in your project?

yarn add @spectrum-web-components/reactive-controllers

Import the PendingStateController via:

import { PendingStateController } from '@spectrum-web-components/reactive-controllers/src/PendingState.js';

Example #

import { LitElement } from 'lit';
import { PendingStateController } from '@spectrum-web-components/reactive-controllers/src/PendingState.js';
class Host extends LitElement{

    /** Whether the items are currently loading. */
    @property({ type: Boolean, reflect: true })
    public pending = false;

    /** Defines a string value that labels the Picker while it is in pending state. */
    @property({ type: String, attribute: 'pending-label' })
    public pendingLabel = 'Pending';
    public pendingStateController: PendingStateController<this>;

    /**
     * Initializes the `PendingStateController` for the Picker component.
     * The `PendingStateController` manages the pending state of the Component.
     */
    constructor() {
        super();
        this.pendingStateController = new PendingStateController(this);
    }
    render(){
        return html`
        <host-element></host-element>
        ${when(
                this.pending,
                () => {
                    return this.pendingStateController.renderPendingState();
                }
            )}
        `
    }

}