My requirement is how to detect the device level notification on/off in android device using javascript (don't use any kind of plug-in only you can use plug-in if this plugin support to PWA application).  As per if notification off I need to show...

Polymer 3 uses import to load external Javascript. For example  import {GoogleCharts} from 'google-charts';   However, it seems for this to work, the external library should use exports.  I am trying to use mapbox-gl.js library. This library,...

I'm trying to understand/implement two way attribute binding in a Polymer 3 web component. I've got the following code:   import {html, PolymerElement} from '@polymer/polymer/polymer-element.js';   class CustomInputComponent extends P...

I am using this polymer-redux repo from github in my examples:     https://github.com/tur-nr/polymer-redux/tree/dev/v2.x   I have the redux-todo component which connects the todoApp with the redux store. I also created a mixin from where I would like...

Is there a way to create a custom event in in Lit-Element/Polymer, such as a mouse-over event? I've been searching for this a while now, but I can seem to find a way of doing it. I know about events in Lit-Element, like @click, but nothing about...

I am working with lit-element 2.0 and I am having an issue where I am getting an error code   Uncaught TypeError: Cannot read property 'querySelectorAll' of undefined  this is the code that is generating the error          console.log(this._r...

I'd like to know how to implement noUiSlider in a web component like Polymer 3/LitElement, I tried the below code which got an error as nouislider.create is not function and the server ended with a response as non-JavaScript MIME type of "tex...

I am learning web components using polymer. I am a beginner in web development.  How can I understand what does dot notation means in .checked attributes or property of HTML element?   <input id="state" type="radio" name=${this.gro...

firstUpdated() {   let element = this.renderRoot.getElementById('input');       element.addEventListener('focusout', e => {         this.inputFocus = false;         this.requestRender();       }); }  <dropdown-list id="list&...

I'm running into "TypeError: Constructor requires 'new' operator" at line 4 of    function PropertiesChanged() {   var _this;   babelHelpers.classCallCheck(this, PropertiesChanged);   _this = babelHelpers.possibleConstructorReturn...