Custom Elements in ES2015 / JS6

Question

What is the ES205 / JS6 way, to make a custom element equivalent to this one made by DartLang

@CodeiSir I found this, but not catching the point https://github.com/domenic/webcomponents/blob/constructor-dmitry-revisions/proposals/Constructor-Dmitry.md — Hasan A Yousef, Nov 26 '15 at 20:03
@CodeiSir, this site was helpful to me, and I posted my solution below: https://www.code-labs.io/codelabs/chrome-es2015/index.html?index=..%2F..%2Fchrome-dev-summit&viewga=UA-41980257-1#0 — Hasan A Yousef, Nov 27 '15 at 21:02
@Blazemonger this question is not a duplicate of what you are considering, pls re read both of them, and the techniques used in solving each — Hasan A Yousef, Nov 30 '15 at 19:59
Perhaps you should spend some time **explaining** your answers, then, as well as providing details in your questions to indicate why they're different from other questions. As it is, you're just pasting similar-looking code over and over again in what looks like an effort to rack up points. — Blazemonger, Nov 30 '15 at 21:07

score 1 · Accepted Answer · edited May 23 '17 at 10:30

I was able to do it, below is how I did it for those who are interested to do so:

       "use strict";

   // DART: class SaveBtn extends HtmlElement { static final tag = 'save-button';
   // ES2015 / JS6
   class SaveBtn extends HTMLElement {

   // DART: factory SaveBtn([String name]) => (new Element.tag(tag) as SaveBtn)..name = name;
   // ES2015 / JS6 
   constructor() {
       super();    
    }

    // DART:  SaveBtn.created() : super.created() {
    // ES2015 / JS6   
    createdCallback(){
        //  Create a Shadow Root, DART & ES2015
        var shadow = this.createShadowRoot();
        // Create a standard element and set it's attributes.
        // DART: innerButton = new ButtonElement()..id='btn';
        // ES2015 / JS6
        var innerButton = document.createElement('button');
        innerButton.id='btn';

        innerButton.addEventListener('click',() => console.log('The button had been clicked'));
        shadow.appendChild(innerButton); 
     }

     // DART: void attached() { }
     // ES2015 / JS6
     attachedCallback(){
         console.log(this.dataset);
         console.log(this.textContent);
          this.shadowRoot.querySelector('#btn').textContent = this.textContent != '' ? this.textContent : this.dataset['text'];
      }

      detachedCallback(){

       }

        attributeChangedCallback(textContent) {

        }

        set text(v) {
            this.textContent = v;
        }

        get text() {
             return this.textContent;
        } 
    }

     var MySaveBtn = document.registerElement("save-button", SaveBtn);
     var x = new MySaveBtn;
     x.text = 'test';
     console.log(x.text);
     document.querySelector('#placeholder').appendChild(x);

the HTML file I used was:

  <!doctype html>
  <html lang="en">
  <head>
     <meta charset="UTF-8">
     <title>ES2015 / JS6 Custom Elements</title>
     <script src="default.js" type="text/javascript"></script>
  </head>
  <body>

  Here is some non-custom stuff.

  <div id="placeholder"><p>Please wait, loading cool things<p></div>

  <save-button data-text='click this'></save-button>
  </body>

  </html>

another way to solve it without using SHADOWROOT is here

Custom Elements in ES2015 / JS6

1 Answers1