@stringsync/vexml/dist/esm/events/nativebridge.d.ts

MusicXML to Vexflow

import * as components from '../components';
import { Topic } from './topic';
import { EventListener } from './types';
export type EventMapping<V extends string[]> = {
    src: 'scroll' | 'overlay';
    vexml: V;
    native: {
        [K in keyof HTMLElementEventMap]?: EventListener<HTMLElementEventMap[K]>;
    };
};
/**
 * This class is responsible for lazily managing the activation and deactivation of native events on a host element.
 *
 * - Activation is the process initializing the native event machinery needed for a given vexml event.
 * - Deactivation is the process of cleaning up the native event machinery when a given vexml event is no longer needed.
 * - Native events are only added to the host element when they are needed.
 */
export declare class NativeBridge<V extends string> {
    private root;
    private mappings;
    private nativeEventTopic;
    private nativeEventOpts;
    private handles;
    constructor(root: components.Root, mappings: Array<EventMapping<V[]>>, nativeEventTopic: Topic<HTMLElementEventMap>, nativeEventOpts: {
        [K in keyof HTMLElementEventMap]?: AddEventListenerOptions;
    });
    /** Returns whether the vexml event is activated. */
    isActivated(vexmlEventName: V): boolean;
    /**
     * Activates a vexml event, initializing the native event machinery if needed.
     *
     * NOTE: vexml events cannot be activated if they are already active. It is the caller's responsibility to ensure that
     * the event is not already active.
     */
    activate(vexmlEventName: V): void;
    /**
     * Deactivates a vexml event, cleaning up the native event machinery if needed.
     *
     * NOTE: vexml events cannot be deactivated if they are already inactive. It is the caller's responsibility to ensure
     * that the event is not already inactive.
     */
    deactivate(vexmlEventName: V): void;
    /** Deactivates all vexml events. */
    deactivateAll(): void;
    /**
     * Forwards a native event to its respective topic.
     *
     * NOTE: This is done in this manner so we can have a reference to the function that is added as a native event
     * listener. This is necessary for unsubscribing from the native event listener when the dependent vexml events are
     * deactivated.
     */
    private publishNativeEvent;
}