Source: carousel.js

/**
 * Carousel Component<BR>
 * <BR><BR><img src=/tk/lib/components/w/img/carousel.png width=90% style="border:1px lime dashed;padding:20px">
 * <BR><BR><a href="/tk/lib/components/w/html/carousel.html">DEMO</a>
 */
class Carousel extends HTMLElement {
    constructor() {
        wc.group("Carousel.constructor")
	
        super();

        wc.groupEnd();
    };
    
    /**
     * Set observable values here. When Changed, attributeChangedCallback is invoked
     * @observedAttributes
     */
    static get observedAttributes() {
        wc.group("Carousel.observedAttributes");

	this.observables = [];

        wc.groupEnd();
        return this.observables;
    };

    /**
     * This function is called when this is attached to DOM
     * @connectedCallback. 
     */
    connectedCallback() {
        wc.group("Carousel.connectedCallback")
	
	let self = this;

	// GET PROPERTIES AND INTERESTING ELEMENTS
	this._initialize();

	// REPLACE CONTENT IF NECESSARY WITH NEW STUFF
	this.innerHTML = this.dom.content;

	this.classList.add("slider");
	this.classList.add("responsive");

	var opts = JSON.parse(this.getAttribute("options"));

	var options = {
	    dots:		typeof opts.dots	   === "undefined" ? false : opts.dots,
	    speed:		typeof opts.speed	   === "undefined" ? false : opts.speed,
	    swipe:		typeof opts.swipe	   === "undefined" ? false : opts.swipe,
	    autoplay:		typeof opts.autoplay	   === "undefined" ? false : opts.autoplay,
	    arrows:		typeof opts.arrows	   === "undefined" ? true  : opts.arrows,
	    infinite:		typeof opts.infinite	   === "undefined" ? true  : opts.infinite,
	    slidesToShow:	typeof opts.slidesToShow   === "undefined" ? false : opts.slidesToShow,
	    slidesToScroll:	typeof opts.slidesToScroll === "undefined" ? 1     : opts.slidesToScroll,
	    initialSlide:	typeof opts.initialSlide   === "undefined" ? 0     : opts.initialSlide,
	};

	wc.log("OPTIONS:", options);

	$(this).slick({
	    speed:	    options.speed,
	    dots:	    options.dots,
	    autoplay:	    options.autoplay,
	    arrows:	    options.arrows,
	    swipe:	    options.swipe,
	    slidesToShow:   options.slidesToShow,
	    slidesToScroll: options.slidesToScroll,
	    initialSlide:   options.initialSlide,
	    infinite:	    options.infinite,
	    pauseOnHover:   true,
	    mobileFirst:    true,

	    responsive: [{
		breakpoint: 1024,
		settings: {
		    slidesToShow: 3,
		    slidesToScroll: 3,
		}
	    }, {
		breakpoint: 600,
		settings: {
		    slidesToShow: 2,
		    slidesToScroll: 2,
		}
	    }, {
		breakpoint: 480,
		settings: {
		    slidesToShow: 1,
		    slidesToScroll: 1,
		}

	    }]
	});

	// ADD STATS AND OTHER FINAL STUFF
	this._finalize();

	// PUBLISH INTERESTING EVENTS
	//this._publish();
	
        wc.groupEnd();
    };

    /**
     * Publish all events
     * @private
     * @_publish
     */
    _publish() {
	wc.group("Carousel.publish");

	this.addEventListener("click", e => {
	    this._click();
	});
		
	wc.groupEnd();
	return true;
    }

    /**
     * A sample callback usage function - see connectedCallback()
     * @private
     * @_click
     */
    _click() {
	wc.group("Carousel._click:", this.id);

	wc.publish("wc-carousel", {
	    time: new Date().getTime(),
	    action: "click",
	    id: this.id,
	    uparam: this.properties.uparam
	});

	wc.groupEnd();
    };

    /**
     * Invoked When component is removed. Usually with a .remove() function call
     * @disconnectedCallback
     */
    disconnectedCallback() {
        wc.group("Carousel.disconnectedCallback")

	/* CLEAN UP NOW */

        wc.groupEnd();
    };

    /**
     * Called with .setAttribute(...) function call
     * @attributeChangedCallback
     */
    attributeChangedCallback(attr, oldval, newval) {
        wc.group("Carousel.attributeChangedCallback:", attr, oldval, newval);

	this.properties = this.properties || [];

	let obs = Carousel.observedAttributes;

	for (let i = 0; i < obs.length; i++) {
	    if (newval) {
		this.properties[obs[i]] = newval;
	    }
	}
	
	// YOUR CODE FOR CHANGES GO HERE (MAYBE NULL FIRST TIME THROUGH)
	try {
	    switch(attr) 
	    {
		case "background":
		break;
		
		default:
		break;
	    }
	}
	catch(e) {
	    wc.warn(e.name + ' > ' + e.message);
	}

        wc.groupEnd();
    };

    /**
     * Stores DOM elements of interest for future use
     * @private
     * @_fetchElements
     */
    _fetchElements() {
	wc.group("Carousel._fetchElements");
	
	this.dom = this.dom || [];
	this.dom.content = this.innerHTML;

	wc.groupEnd();
    };

    /**
     * Component attributes are _fetched and defaults are set if undefined
     * @private
     * @_fetchAttributes
     * @param {string} [modal=true] mode for our carousel
     */
    _fetchAttributes() {
	wc.group("Carousel._fetchAttributes");
	
	this.properties = {
	    cname      : "Carousel",
	    author     : "Mel Heravi",
	    version    : "1.0"
	};
	
	// SAVE WIDGET SPECIFIC PROPERTIES
	this.propertiesW = [];

	// SAVE ALL OTHER PROPERTIES
	let attrs = wc.getAttributes(this)
	
 	for (var key in attrs) {
	    let attr = this.getAttribute(key) || this.properties.key;
	    this.properties[key]  = this.getAttribute(key);
	    this.propertiesW[key] = this.getAttribute(key);
	    wc.log(key + ": " + attrs[key]);
	}

	// SET ALL INITIAL ATTRIBUTES
 	for (var key in this.properties) {
	    switch(key) 
	    {
		case "background":
		break;
		
		case "header":
		break;
		
		default:
		break;
	    }
	}

	wc.log("ATTRIBUTES: ", this.properties);

	wc.groupEnd();
    };

    /**
     * A sample callback usage function - see connectedCallback()
     * @private
     * @_onClick
     */
    _onClick() {
	wc.group("Carousel._onClick:", this.id);

	wc.publish("wc-carousel", {
	    action: "click",
	    id: this.id,
	    uparam: this.properties.uparam
	});

	wc.groupEnd();
    };

    /**
     * Destroy the instance object and artifacts
     * @private
     * @_destroy
     */
    destroy() {
	wc.group("Carousel.destroy:", this.id);

	// FREE ALL MEMORY
	// you should delete all created objects here

	// FREE POINTER
	delete this;

	// REMOVE ITEM FROM DOM
	this.parentNode.removeChild(this);

	wc.groupEnd();
    };

    /**
     * configure the instance object and artifacts
     * @private
     * @_configure
     */
    configure(options) {
	wc.group("Carousel.configure:", JSON.stringify(options));

	// PROCESS ALL OPTIONS HERE

	wc.groupEnd();
    };

    /**
     * SAVE DATA FOR ANALYTICS
     * @private
     * @_initialize
     */
    _initialize() {
	wc.group("Carousel._initialize:", this.id);

	// FETCH ALL INTERESTING ELEMENTS
	this._fetchElements();

	// FETCH ALL ATTRIBUTES
	this._fetchAttributes();
	
	wc.groupEnd();
    };

    /**
     * SAVE DATA FOR ANALYTICS
     * @private
     * @_finalize
     */
    _finalize() {
	wc.group("Carousel._finalize:", this.id);

	this.classList.add("wc");

	// ADD ANALYTICS HERE
	wc.setStats(this, this.properties.cname, this.properties.version);
	
	// SHOW IT NOW (NO FLICKERS) 
	this.style.visibility = "visible";

	this._caption();

	$(window).resize(e => {
	    $(".wc-carousel-img-caption").each(function() {
		let w = $(this).parent().parent().width() - 50;

		$(this).css({
		    "width": w + "px",
		    "position":"relative",
		    "z-index": 999999,
		    "background": red
		});
	    });
	});

	wc.groupEnd();
    };

    /**
     * SAVE DATA FOR ANALYTICS
     * @private
     * @_caption
     */
    _caption() {
	wc.group("Carousel._caption:", this.id);

	let self = this;

	$("#" + this.id + " [slick-caption]").each(function() {
	    let caption = $(this).attr("slick-caption");
	    
	    let w = $(this).width() - 50;

	    $(this).parent().append("<span>" + caption + "</span>");
	});

	wc.groupEnd();
    };
}

window.customElements.define('wc-carousel', Carousel);