How to use the react-native-notifications.getDeliveredNotifications function in react-native-notifications

clearChannelNotifications(channelId) {
        NotificationsIOS.getDeliveredNotifications((notifications) => {
            const ids = [];
            let badgeCount = notifications.length;

            if (this.reduxStore) {
                const totalMentions = getBadgeCount(this.reduxStore.getState());
                if (totalMentions > -1) {
                    badgeCount = totalMentions;
                }
            }

            for (let i = 0; i < notifications.length; i++) {
                const notification = notifications[i];

                if (notification.channel_id === channelId) {
                    ids.push(notification.identifier);
                }

getDeliveredNotifications(callback) {
        NotificationsIOS.getDeliveredNotifications(callback);
    }