POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor.

ABOUT POLYMER 1.0

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES REGISTRATION AND LIFECYCLE

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor.

ABOUT POLYMER 1.0

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES REGISTRATION AND LIFECYCLE

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

POLYMER LIBRARY

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling ENCAPSULATED ROUTING WITH ELEMENTS Introduction. Polymer is designed with a set of principles in mind: encapsulation, composition, and separation of concerns. When we set out to tackle routing, we knew we wanted to do it in a way that adheres to these principles. Most client side routers are monolithic black boxes that require a complete and centralized route

configuration with

OBSERVERS AND COMPUTED PROPERTIES Observers are methods invoked when observable changes occur to the element's data. There are two basic types of observers: Simple observers observe a single property. Complex observers can observe one or more properties or paths.; You use different syntax for declaring these two types of observers, but in most cases they function the same

way.

PUBLISH AN ELEMENT

Publish. There are two steps to publishing an element on GitHub: Push your work to a GitHub repo and tag it with a release number, so people can install it using Bower. In this step you create a master branch containing the bare-minimum of code that needs to be consumed by other

apps or elements.

POLYMER 3.0: NEW YEAR, NEW PREVIEW npm replaces Bower. For more details, you can see the original announcement: Polymer 3.0 preview: npm and ES6 Modules. Polymer 3.0 is intended to be a purely mechanical upgrade, using the Polymer Modulizer tool. We're using this tool to convert the core library and our elements. You'll be able to use this tool to convert your

elements, too.

STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

HANDLE AND FIRE EVENTS By default, custom events stop at shadow DOM boundaries. To make a custom event pass through shadow DOM boundaries, set the composed flag to true when you create the event: var event = new CustomEvent ('my-event', {bubbles: true, composed: true}); Backwards compatibility. The fire instance method in the legacy API sets both bubbles and composed BUILD FOR PRODUCTION Even simpler starter. The rollup-starter-app repo is a bare-bones starter project for building an app with Rollup. Although the repo doesn’t include LitElement, it includes everything you need to bundle a LitElement app. If you want to use this project as a model for your own project, the most important files to look at are package.json and rollup.config.js.

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once

"DIRECTIVES/GUARD"

Example: html` < div > ${guard(, => html``)} In this case, the template only renders if either user.id or company.id changes.. guard() is useful with immutable data patterns, by preventing expensive work until data updates.

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once

"DIRECTIVES/GUARD"

Example: html` < div > ${guard(, => html``)} In this case, the template only renders if either user.id or company.id changes.. guard() is useful with immutable data patterns, by preventing expensive work until data updates.

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor. ENCAPSULATED ROUTING WITH ELEMENTS Introduction. Polymer is designed with a set of principles in mind: encapsulation, composition, and separation of concerns. When we set out to tackle routing, we knew we wanted to do it in a way that adheres to these principles. Most client side routers are monolithic black boxes that require a complete and centralized route

configuration with

ABOUT POLYMER 1.0

Benchmarks. As a sample of the performance difference between 0.5 and 1.0, the results from our medium-list benchmark was that Polymer 1.0 was about 3x faster on Chrome and 4x faster on Safari. The benchmark measures time to first paint for an application with a few thousand nested custom elements, with data binding.

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling EVENTS – LITELEMENT Add event listeners in connectedCallback. connectedCallback is a lifecycle callback in the custom elements API.connectedCallback fires each time a custom element is appended into a document-connected element. See the MDN documentation on using custom elements lifecycle callbacks for more information.. If your component adds an event listener to anything except itself or its children–for

LIT-HTML

Repeating templates. Rendering nothing. Caching template results: the cache directive. lit-html is a templating library that provides fast, efficient rendering and updating of HTML. It lets you express web UI as a function of data. This section introduces the main features and concepts in lit-html.

USING DECORATORS

Using decorators. Decorators are special expressions that can alter the behavior of class, class method, and class field declarations. LitElement supplies a set of decorators that reduce the amount of boilerplate code you need to write when defining a component.

POLYMER LIBRARY

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor.

ABOUT POLYMER 1.0

OBSERVERS AND COMPUTED PROPERTIES OBSERVERS AND COMPUTED PROPERTIES EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom REGISTRATION AND LIFECYCLE STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

POLYMER LIBRARY

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor.

ABOUT POLYMER 1.0

OBSERVERS AND COMPUTED PROPERTIES OBSERVERS AND COMPUTED PROPERTIES EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom REGISTRATION AND LIFECYCLE STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

POLYMER LIBRARY

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

DECLARE PROPERTIES

Key Details; type: Type: constructor . Attribute type, used for deserializing from an attribute. Polymer supports deserializing the following types: Boolean, Date, Number, String, Array and Object.You can add support for other types by overriding the element's _deserializeValue method.. Unlike 0.5, the property's type is explicit, specified using the type's constructor.

ABOUT POLYMER 1.0

Benchmarks. As a sample of the performance difference between 0.5 and 1.0, the results from our medium-list benchmark was that Polymer 1.0 was about 3x faster on Chrome and 4x faster on Safari. The benchmark measures time to first paint for an application with a few thousand nested custom elements, with data binding. ENCAPSULATED ROUTING WITH ELEMENTS Introduction. Polymer is designed with a set of principles in mind: encapsulation, composition, and separation of concerns. When we set out to tackle routing, we knew we wanted to do it in a way that adheres to these principles. Most client side routers are monolithic black boxes that require a complete and centralized route

configuration with

REGISTRATION AND LIFECYCLE Register a custom element. To register a custom element, use the Polymer function, and pass in the prototype for the new element. The prototype must have an is property that specifies the HTML tag name for your custom element.. By specification, the custom element's name must contain a dash (-).. Example:

POLYMER CLI

Polymer CLI is a command-line interface for Polymer projects. It includes a build pipeline, a boilerplate generator for creating elements and apps, a linter, a development server, and a test runner. Polymer CLI works with two types of projects: Elements projects. OBSERVERS AND COMPUTED PROPERTIES Observers are methods invoked when observable changes occur to the element's data. There are two basic types of observers: Simple observers observe a single property. Complex observers can observe one or more properties or paths.; You use different syntax for declaring these two types of observers, but in most cases they function the same

way.

PUBLISH AN ELEMENT

Publish. There are two steps to publishing an element on GitHub: Push your work to a GitHub repo and tag it with a release number, so people can install it using Bower. In this step you create a master branch containing the bare-minimum of code that needs to be consumed by other

apps or elements.

BUILD FOR PRODUCTION Even simpler starter. The rollup-starter-app repo is a bare-bones starter project for building an app with Rollup. Although the repo doesn’t include LitElement, it includes everything you need to bundle a LitElement app. If you want to use this project as a model for your own project, the most important files to look at are package.json and rollup.config.js.

LIT-HTML

Repeating templates. Rendering nothing. Caching template results: the cache directive. lit-html is a templating library that provides fast, efficient rendering and updating of HTML. It lets you express web UI as a function of data. This section introduces the main features and concepts in lit-html.

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

ABOUT POLYMER 1.0

Benchmarks. As a sample of the performance difference between 0.5 and 1.0, the results from our medium-list benchmark was that Polymer 1.0 was about 3x faster on Chrome and 4x faster on Safari. The benchmark measures time to first paint for an application with a few thousand nested custom elements, with data binding. OBSERVERS AND COMPUTED PROPERTIES Computed properties are virtual properties based on one or more pieces of the element's data. A computed property is generated by a computing function—essentially, a complex observer that returns a value. Unless otherwise specified, notes about observers apply to simple observers, complex observers, and computed properties. STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom EVENTS – LITELEMENT Add event listeners in connectedCallback. connectedCallback is a lifecycle callback in the custom elements API.connectedCallback fires each time a custom element is appended into a document-connected element. See the MDN documentation on using custom elements lifecycle callbacks for more information.. If your component adds an event listener to anything except itself or its children–for

LIT-HTML

Repeating templates. Rendering nothing. Caching template results: the cache directive. lit-html is a templating library that provides fast, efficient rendering and updating of HTML. It lets you express web UI as a function of data. This section introduces the main features and concepts in lit-html.

USING DECORATORS

Using decorators. Decorators are special expressions that can alter the behavior of class, class method, and class field declarations. LitElement supplies a set of decorators that reduce the amount of boilerplate code you need to write when defining a component.

PWA STARTER KIT

About PWA Starter Kit. This project is no longer under development. This documentation site and the GitHub repo are still available for reference. If you're interested in continuing to use PWA Starter Kit, feel free to fork and modify it as you like. Our other projects, LitElement and lit-html are production-ready and under active

development.

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

ABOUT POLYMER 1.0

Benchmarks. As a sample of the performance difference between 0.5 and 1.0, the results from our medium-list benchmark was that Polymer 1.0 was about 3x faster on Chrome and 4x faster on Safari. The benchmark measures time to first paint for an application with a few thousand nested custom elements, with data binding. OBSERVERS AND COMPUTED PROPERTIES Computed properties are virtual properties based on one or more pieces of the element's data. A computed property is generated by a computing function—essentially, a complex observer that returns a value. Unless otherwise specified, notes about observers apply to simple observers, complex observers, and computed properties. STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom EVENTS – LITELEMENT Add event listeners in connectedCallback. connectedCallback is a lifecycle callback in the custom elements API.connectedCallback fires each time a custom element is appended into a document-connected element. See the MDN documentation on using custom elements lifecycle callbacks for more information.. If your component adds an event listener to anything except itself or its children–for

LIT-HTML

Repeating templates. Rendering nothing. Caching template results: the cache directive. lit-html is a templating library that provides fast, efficient rendering and updating of HTML. It lets you express web UI as a function of data. This section introduces the main features and concepts in lit-html.

USING DECORATORS

Using decorators. Decorators are special expressions that can alter the behavior of class, class method, and class field declarations. LitElement supplies a set of decorators that reduce the amount of boilerplate code you need to write when defining a component.

PWA STARTER KIT

About PWA Starter Kit. This project is no longer under development. This documentation site and the GitHub repo are still available for reference. If you're interested in continuing to use PWA Starter Kit, feel free to fork and modify it as you like. Our other projects, LitElement and lit-html are production-ready and under active

development.

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

API REFERENCE

API Reference - Polymer.Element - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 2.x Tutorial: Build an element 1. Get set up 2. Add local DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 2.0 Upgrade guide Hybrid

elements Release

EVENTS - POLYMER PROJECT Use Polymer.dom (event) to get a normalized event object that provides equivalent target data on both shady DOM and shadow DOM. Specifically, the normalized event has the following properties: rootTarget: The original or root target before shadow retargeting (equivalent to event.path under shadow DOM or event.target under shady DOM). OBSERVERS AND COMPUTED PROPERTIES STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

INTRODUCTION

LitElement is a simple base class for creating fast, lightweight web components that work in any web page with any framework. LitElement uses lit-html to render into shadow DOM, and adds API to manage properties and attributes. Properties are observed by default, and elements update asynchronously when their properties change. DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom

SAMPLE APPS

Books ( code, demo) app that searches for books using the Google Books API. shows how to use the Embedded Viewer API to display book content. shows how to use the Google Books API to list/update favorites on the authenticated user’s bookshelf. pattern for using UI loading placeholders. pattern for re-fetching data when the network state

changes.

LIT-HTML

lit-html is a simple, modern, safe, small and fast HTML templating library for JavaScript. lit-html lets you write HTML templates in JavaScript using template literals with embedded JavaScript expressions. lit-html identifies the static and dynamic parts of your

templates so it

STYLES – LITELEMENT The static styles property is usually the best way to add styles to your component, but there are some use cases you can’t handle this way—for example, linking to an external style sheet. For alternate ways to add styles, see Define scoped styles in the template.. Expressions in static styles. Static styles apply to all instances of a component. Any expressions in CSS are evaluated once LIFECYCLE – LITELEMENTSEE MORE ON LIT-ELEMENT.POLYMER-PROJECT.ORG

POLYMER LIBRARY

The Polymer library is in maintenance mode. For new development, we recommend Lit . The Polymer library provides a set of features for creating custom elements. These features are designed to make it easier and faster to make custom elements that work like standard DOM elements. Similar to standard DOM elements, Polymer elements can be:

DECLARE PROPERTIES

Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling

ABOUT POLYMER 1.0

Benchmarks. As a sample of the performance difference between 0.5 and 1.0, the results from our medium-list benchmark was that Polymer 1.0 was about 3x faster on Chrome and 4x faster on Safari. The benchmark measures time to first paint for an application with a few thousand nested custom elements, with data binding. OBSERVERS AND COMPUTED PROPERTIES Computed properties are virtual properties based on one or more pieces of the element's data. A computed property is generated by a computing function—essentially, a complex observer that returns a value. Unless otherwise specified, notes about observers apply to simple observers, complex observers, and computed properties. STEP 3: USE DATA BINDING AND PROPERTIES Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling DOM-REPEAT – API REFERENCE dom-repeat – API Reference - Polymer Project. Search Polymer site. Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom EVENTS – LITELEMENT Add event listeners in connectedCallback. connectedCallback is a lifecycle callback in the custom elements API.connectedCallback fires each time a custom element is appended into a document-connected element. See the MDN documentation on using custom elements lifecycle callbacks for more information.. If your component adds an event listener to anything except itself or its children–for

LIT-HTML

Repeating templates. Rendering nothing. Caching template results: the cache directive. lit-html is a templating library that provides fast, efficient rendering and updating of HTML. It lets you express web UI as a function of data. This section introduces the main features and concepts in lit-html.

USING DECORATORS

Using decorators. Decorators are special expressions that can alter the behavior of class, class method, and class field declarations. LitElement supplies a set of decorators that reduce the amount of boilerplate code you need to write when defining a component.

PWA STARTER KIT

About PWA Starter Kit. This project is no longer under development. This documentation site and the GitHub repo are still available for reference. If you're interested in continuing to use PWA Starter Kit, feel free to fork and modify it as you like. Our other projects, LitElement and lit-html are production-ready and under active

development.

Polymer Project

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Black Lives Matter. Support the Equal Justice Initiative and Campaign Zero

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Polymer Project

Libraries, tools, and standards for a better web: LitElement

, lit-html

, web components...

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LITELEMENT

A simple base class for creating fast, lightweight web components.

LIT-HTML

An efficient, expressive, extensible HTML templating library for

JavaScript.

MATERIAL WEB COMPONENTS High-fidelity realizations of Google's Material Design spec that work anywhere on the web.

Prerelease

WEB COMPONENTS POLYFILLS A suite of polyfills supporting the Web Components specs.

POLYMER LIBRARY

Our original web component library.

Maintenance

POLYMER ELEMENTS

Our original sets of web components, built with the Polymer library.

Maintenance

ABOUT THE POLYMER PROJECT AS FRONT-END ENGINEERS IN THE CHROME TEAM, OUR MISSION IS TO MAKE THE

WEB BETTER.

WE WORK ON

LIBRARIES & TOOLS

to help developers unlock the web’s full potential, taking advantage of cutting-edge features like Web Components, Service Workers and

HTTP/2.

WE EXPERIMENT WITH

NEW PATTERNS

for building faster and smaller web applications.

WE ADVOCATE FOR

STANDARDS

helping ensure that web developers have a strong voice in the process.

WHY WEB COMPONENTS?

We’re best known for our work on Web Components, a set of modern web standards that give you the power to extend HTML. With Web Components, you can create and share custom elements that work on any site, interoperate seamlessly with the browser’s built-in elements, and play nicely with frameworks of all kinds. If you like, you can build your app entirely out of Web Components. Breaking your app up into right-sized components helps make your code cleaner and less expensive to maintain. Products like LitElement and PWA Starter Kit make Web Components easier to use and highlight best practices, helping you get great

results.

Learn more

LATEST NEWS

LITELEMENT 3.0 & LIT-HTML 2.0: EARLY PREVIEW RELEASE Preview the next major versions of LitElement and lit-html.

Blog Post

NATIVE WEB COMPONENTS COME TO MICROSOFT EDGE With the release of Microsoft's new Chromium-based Edge, all major evergreen browsers now support Web Components natively.

Blog Post

LIGHTNING-FAST TEMPLATES & WEB COMPONENTS: LIT-HTML & LITELEMENT

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Copyright 2015–2020 The Polymer Project Authors. Code licensed under the BSD License . Documentation licensed under CC BY 3.0.