Source: dialog.js

/**
 * Dialog Component<BR>
 * <BR><BR><img src=/tk/lib/components/w/img/dialog.png width=30% style="border:1px lime dashed;padding:20px">
 * <BR><BR><a href="/tk/lib/components/w/html/dialog.html">DEMO</a>
 */
class Dialog extends HTMLElement {
    constructor() {
        wc.group("Dialog.constructor")
	
        super();

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

	this.observables = [];

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

    /**
     * Initial Markup
     * @private
     * @_template
     */
    _template() {
        wc.group("Dialog.template");
	
	let t = this.querySelector("wc-dialog-title").innerHTML;
	let b = this.querySelector("wc-dialog-body").innerHTML;
	let c = this.querySelector("wc-dialog-controls");
	
	if (c) {
	    c = '<div class="modal-footer">' + c.innerHTML + '</div>';
	} else {
	    c = "";
	}
	
	if (this.properties.closeable == "true") {
	    var close = '<button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>';
	} else {
	    var close = "";
	}

	let id = this.id + "-modal";

	var temp = `
	<div class="modal" id="${id}" tabindex="-1" role="dialog" aria-labelledby="${id}-label" aria-hidden="true">
	    <div class="modal-dialog" role="document">
		<div class="modal-content" style="width:${this.properties.width};height:${this.properties.height};margin-top:${this.properties.top}">
		    <div class="modal-header">
			<h5 class="modal-title" id="${id}-label">${t}</h5>

			${close}
		    </div>

		    <div class="modal-body">
			${b}
		    </div>

		    ${c}
		</div>
	    </div>
	</div>`

        wc.groupEnd();
        return temp;
    };

    /**
     * Called when this is attached to DOM
     * @connectedCallback. 
     */
    connectedCallback() {
        wc.group("Dialog.connectedCallback")
	
	// GET PROPERTIES AND INTERESTING ELEMENTS
	this._initialize();

	// ADD COMPONENT MARKTOP
	this.innerHTML = this._template()

	// PUBLISH EVENTS
	this._publish();
	
	// REPOSITION WHEN A MODAL IS SHOWN
	$('.modal').on('show.bs.modal', this._reposition);

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

        wc.groupEnd();
    };

    /**
     * Centers the dialog
     * @private
     * @_reposition
     */
    _reposition() {
	wc.group("Dialog._reposition");

        var modal = $(this), dialog = modal.find('.modal-dialog');
        modal.css('display', 'block');
        
        // Dividing by two centers the modal exactly, but dividing by three 
        // or four works better for larger screens.
        dialog.css("margin-top", Math.max(0, ($(window).height() - dialog.height()) / 2));

	wc.groupEnd();
    }

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

	let c = this.querySelectorAll(".modal-footer .btn");
	
	$(c).each(function() {
	    $(this).on("click", function() {
		wc.publish("wc-dialog", {
		    time: new Date().getTime(),
		    action: "click",
		    id: this.id
		});
	    });
	});
	
	wc.groupEnd();
    }

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

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

	let obs = Dialog.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 "header":
		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("Dialog._fetchElements");
	
	this.dom = this.dom || [];
	this.dom.content = this.innerHTML;

	wc.groupEnd();
    };

    /**
     * Component attributes are _fetched and defaults are set if undefined
     * @private
     * @_fetchAttributes
     */
    _fetchAttributes() {
	wc.group("Dialog._fetchAttributes");
	
	this.properties = {
	    cname	: "Dialog",
	    author	: "Mel M. Heravi",
	    version	: "1.0",
	    width	: "400px",
	    height	: "250px",
	    top		: "100px",
	    closeable	: "true"
	};
	
	// 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 "header":
		break;
		
		default:
		break;
	    }
	}

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

	wc.groupEnd();
    };

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

	// PROCESS ALL OPTIONS HERE

	wc.groupEnd();
    };

    /**
     * Initialize component
     * @private
     * @_initialize
     */
    _initialize() {
	wc.group("Dialog._initialize:", this.id);

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

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

    /**
     * Save data for analytics and final wrap up
     * @private
     * @_finalize
     */
    _finalize() {
	wc.group("Dialog._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";

	wc.groupEnd();
    };

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

	// FREE MEMORY AND CLEANUP

        wc.groupEnd();
    };
}

window.customElements.define('wc-dialog', Dialog);