Where communities thrive

  • Join over 1.5M+ people
  • Join over 100K+ communities
  • Free without limits
  • Create your own community
Repo info
    Shaihd Nauman
    How come I know that which web component is dependent on my component? Or in simple words, my component is included as dependencies of which other webcomponent over "webcomponents.org"?
    Hi! I have a question. What do you guys think that to use web components or situation of using web components?
    I’m usually using React.js, also I don’t wanna write components in .html. web components, especially web components with lit-html or litElement is cool combination but if I make new app, it would rather useful to use React.js itself.
    I've read Micro Frontends. https://micro-frontends.org/
    If I implement feature for big or midium app which several team are involved with it, it would be nice to make components by using web components, but if not, I can’t come up any idea. What do you think about it?
    Avichay Eyal
    Web compoments are futute proof, for the "day after react". Rewriting the ui is expensive and time consuming which you can avoid
    I know React will be obsolete someday. but I don’t think React will be obsolete right now and at least a year. I’m kind of feeling like waste of time if I adapt to use web components for making new app as a main view component.
    Avichay Eyal
    @takahiro-saeki Micro frontends are an approach to deal with multiple client-side frameworks or multiple stacks that might have conflicts and naively cannot be used together on the same application
    Web Components are just one part of dealing with the situation.
    I would advise to create the “atomic” or “molecules” parts of the UI with web components standards as it would save time in the future porting them into new stack. The “main” view or those big parts who consist some logic may be written anyway you like, because they are easier to migrate.
    Dzintars Klavins
    @takahiro-saeki I share with you your thoughts about React. I am programming newbie in general, but started to build my enterprise level Web App with Go and vanilla Web Components. Yes, they doesn't work on all browsers, yes, there are some small issues with SVG... but i really don't care. I believe that i will have the huge benefit in long term to have own component library and i believe that at time of releasing my software WC will be implemented in all major browsers.
    I don't think React's vDOM diffing is the most effective way to re-render whole UI
    Avichay Eyal
    @takahiro-saeki If performance is on the table: shadow-dom is fast as the styles computing is less expensive. If the elements are built correctly, you beat the VDOM by far. https://i.imgur.com/k0GFfb7.png
    slim.js is web components based, it's as fast as VDOM.
    Avichay Eyal
    If anyone is interested, I just had a talk at a meet up at Sisense (Tel-Aviv) about web components and WHY web components, here are the slides. https://docs.google.com/presentation/d/13PMwoT9OWgwugiQ5fxrA5Ht8t8jFmQCflV0DOnOjDso
    I'm creating a Polymer 3 app, and I need to upload an Image with AJAX and grab request. I cannot make iron-form work for me. I've seen some interesting components but all require Bower and not NPM as specified by Polymer 3. Can anyone help me? What could I use? Can I use bower components too or do you know of any NPM components I may use? Many thanks indeed
    Hi all,
    I am a newbie.
    How to use https://ga-dev-tools.appspot.com/polymer-elements/ ?
    Please help me. Thank you very much.

    Hi to all, we build a library to create web components heres a demo

    Hope your feedback thanks.

    Binh Bui
    @quangpro1610 What do you need help with?
    @binhbbbb Thank you for response, I have completed my work with this tool.
    Hi guys here is some updating I've done to x-tag v1 => https://github.com/KipOmaha/HTMLElements-XTag. I was just wondering if anyone is using this and was interested in updating it, because v2 is still beta. If your using it and was interested in an update pipe in on the issues in the repo.
    Hi Guys, need some input. Recently there is vulnerability reported with event-stream.js and Webcomponents-lite.js has a dependency on this library. What y'all expert think about it. I am not sure for what specific purpose is event-stream getting used and should we be concerned. We are using Polymer for building a highly secure financial application and any such vulnerability raises a huge concern. Your input is much appreciated
    Andrew Robbins
    I'm not sure who to ask
    but the demos on webomponents.org are not working
    there is a warning
    "Warning: You're viewing the Bower docs. This element has migrated to NPM."
    how do I view the demos on npm?
    Andrew Robbins
    n/m, I found the demos on npm, and it just redirects to webcomponents.org
    Hi all, I needed some guidance on how to fix the document.registerElement depreciation warning for Chrome M73 version. Right now I am using version 0.6.0-58c8709 of webcomponents.lite.js which is an old version.
    Do I need to update the library to latest polyfills? Or the old version will still be fine to go with as I do see in FF and IE where document.registerElement is already depreciated polyfill replacing the functionality
    Linda Giorgi

    hi guys!
    I'm a newbie regarding the webcomponents, but I would like to try them out and, to convince my co-workers and management to start using them, I'm preparing a small presentation which include a small demo on how to create a webcomponent.
    I found I really nice example here: https://coryrylan.com/blog/introduction-to-web-components, but I would like to show a WebC is also easily testable and I'm currently blocked: we are using Jest, but I don't understand how I can use it to test a WebC: as soon as I run a simple test I got
    `TypeError: Cannot read property 'define' of undefined

       9 | }
      10 |
    > 11 | window.customElements.define("zp-counter", Counter);
         |                       ^
      12 |
      at Object.define (src/js/counter.js:11:23)
      at Object.<anonymous> (__tests__/counter.js:2:1)

    Any idea what should I include to make Jest work?

    Avichay Eyal
    Correct me if I am wrong, last time I have checked JSDOM does not work with custom elements without polyfills. If you are running unit-tests for web components, you may want to check a dedicated universal tool: showroom.js
    Kartik Sharma
    Can anyone confirms if youtube uses shadow dom or not?
    its built on polymer, but could'nt find any shadow dom ref
    Daan Haitsma
    There are a bunch of custom elements (["yt-activity-manager", "yt-guide-manager", "yt-gfeedback-manager", "yt-navigation-manager", "yt-network-manager", "yt-playlist-manager", "yt-player-manager", "yt-visibility-monitor", "ytd-page-manager", "ytd-playlist-sidebar-renderer", "ytd-settings-sidebar-renderer", "ytd-thumbnail-overlay-time-status-renderer", "ytd-player", "video", "ytd-guide-entry-renderer", "ytd-guide-collapsible-section-entry-renderer", "yt-page-navigation-progress"]), but those indeed do not seem to use shadow dom
    Kartik Sharma
    Wondering is slots can be used without shadow Dom. Also, it seems for internet explorer of YouTube website is rendered instead. Wondering if there are any limitations in polyfills.
    Avichay Eyal
    There is no need for shadow dom in youtube. Therefor it is not used.
    Andreas Hahn
    Shadow Dom is never "needed". It's about using the platform and how to do it.
    Guilherme Humberto
    Hello guys! I would like to make a floating chat component, similar to tawk.to. Do you know if there is a project?
    Avichay Eyal
    @drdreo it's needed of course, depends in the context. Polyner and Lit chose to use shadow dom always, which i think is not always the right case.
    Hari Krishna Gaddipati
    Hi Guys I am trying to use the cellClassNameGenerator property and assigned a function that returns a class name. But the class did not get applied.
    should I set the value of column or returning the class name si enough?
    Help my guys
    I have this web component rendered with lit-html
        <paper-dropdown-menu label="Dinosaurs">
          <paper-listbox slot="dropdown-content" >
    -- To do a search i need the selected value of this paper component, what is the best way to achieve this?
    Tim Sweet
    the paper-dropdown-menu needs to emit events for when the items are changed. if it isn't then you're going to have a harder time
    if it is, then you just need to add the event listener after it is rendered.
    Hey guys I need to create a web components using react and I need to use that Components in html or js file which is present in different folder
    Do we need any dependence packages
    Help me out guys
    Georges Gomes
    Check out React and Preact templates on webcomponents.dev