Method _removeEventHandler

docs/app/js/sanddance-app.js:92434–92456

* Process the event deregistration for a single event + handler.

(event, handler)

    /**
     * Process the event deregistration for a single event + handler.
     */ _removeEventHandler(event, handler) {
        if (typeof event !== "string") {
            // If `event` is a map, call `off()` for each entry.
            for(const eventName in event)this._removeEventHandler(eventName, event[eventName]);
            return;
        }
        const { events  } = this;
        // Alias to a recognized gesture as necessary.
        const eventAlias = (0, _constants.GESTURE_EVENT_ALIASES)[event] || event;
        const eventRegistrar = events.get(eventAlias);
        if (!eventRegistrar) return;
        eventRegistrar.remove(event, handler);
        if (eventRegistrar.isEmpty()) {
            const { recognizerName  } = eventRegistrar;
            // Disable recognizer if no more handlers are attached to its events
            let isRecognizerUsed = false;
            for (const eh of events.values())if (eh.recognizerName === recognizerName && !eh.isEmpty()) {
                isRecognizerUsed = true;
                break;
            }
            if (!isRecognizerUsed) this._toggleRecognizer(recognizerName, false);
        }
    }
}
exports.default = EventManager;