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What Is Web Component and Why You Should Be Using Them?

May 25, 2023 1629 Views

Are you sick and worn out of facing the same old problems in web development? Have you ever struggled with the reuse and maintainability of your code? If so, this article is for you. Web developers run into these problems frequently. This is why web components have gained popularity as a remedy in recent years. Furthermore, we’ll explore the world of web components and the benefits of employing them in this blog post. We’ll also introduce Ext JS, a complete JavaScript framework for creating data-intensive, cross-platform online and mobile applications.

What Are Web Components?

Web components are code chunks that you wrap and reuse. You can also use this on any web page. They are created with a specific purpose in mind and offer a clear division of duties. This makes them simple to maintain and reuse. Using these components, programmers may build modular, adaptable user interface pieces that can be applied to a web platform and application.

Web Component Libraries?

What are web components libraries

Web component libraries are collections of already-made, reusable components that may be applied throughout a complete web application. The goal of these libraries is to offer a standardized collection of UI components that are simple to integrate into web projects, speeding up development and enhancing uniformity throughout an application. Ext JS, Polymer, and LitElement are a few popular web component libraries that each offer a special combination of features and advantages to developers trying to speed up their online development process.

Why Build a Design System Using Web Components?

Creating a design system utilizing web components can have several advantages for web developers and designers. Designers may assure uniformity throughout a web application, increase accessibility, and speed up development by employing web components.

Easy to Customize and Standardize Styles

Using these components, you can easily customize and standardize a web application’s styles. These components can have unique styles that don’t clash with those of other components on the page. This means that by utilizing web components, developers may quickly establish a uniform look and feel throughout an application.

Supported by Modern Browsers

All major browsers, including Chrome, Opera, Safari, Firefox, and Edge, support web components. As a result, developers can use web components to create applications confidently, knowing that their code will function on all popular web browsers.


Web components can be used with any front-end web component framework or component library or even without one because they are framework-independent. Because of this, developers may more easily incorporate web components into current projects without having to rewrite their existing codebases entirely.


It is possible to make web components accessible to everyone, including people with disabilities. A web component must be keyboard focusable to be interactive, including any UI control. Web components are more accessible if they follow practices such as WAI-ARIA Authoring Practices (Web Accessibility Initiative Accessible Rich Internet Applications).


A crucial component of web components, the Shadow DOM, offers style encapsulation. By giving each component its own DOM, the Shadow DOM isolates a component’s styling from the rest of the document. Because you separate styles within a component, code maintenance and updating are simple.

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How Web Components Interact With Other Elements

How Web Components Interact With Other Elements

UI components are made to be largely independent of outside resources. They can still communicate with other page elements via APIs like the Shadow DOM, HTML templates, and custom events.

The Shadow DOM

Shadow DOM provides a method for protecting styles and DOM fragments from being impacted by other styles on the page. To do this, one can build a unique “shadow” DOM tree and tie it to the host element of the web component.

HTML Templates

You can generate reusable code snippets that you can copy and alter as necessary using the custom HTML elements. Although templates are in the HTML markup of the page, they don’t render until JavaScript activates them.

Template Slots

Slots offer a blank space for material that you can fill in at runtime. This allows you to alter the template of a web component. You can place any acceptable HTML content in the slots. This is usually within the shadow DOM of the web component.

The Declarative Shadow DOM

Without utilizing JavaScript, the declarative Shadow DOM enables you to define the shadow DOM for a web component spec using only HTML markup. Since the entire component’s structure and styling can be defined in the HTML markup, this makes it simpler to develop web components that can be rendered on the server.

Using Web Components in Ext JS Framework

Sencha Ext JS is an extensive JavaScript framework that provides a full set of 140+ pre-integrated, high-performance UI components for building cross-platform, data-intensive online and mobile applications for any modern device. These user interface elements come with a wide range of capabilities, such as menus, toolbars, panels, windows, grids, pivot grids, charts, layouts, forms, and more. Hundreds of user extensions are available from the Sencha community in addition to the pre-built components.

Sencha Ext JS has accessibility features that comply with the ADA Standards for Accessible Design. The Ext JS ARIA package offers tools to include accessibility support in applications so that people who use assistive technologies like screen readers to navigate the web can use those applications.

Web Component Issues

Although there have been significant advancements in Web Component development, some potential problems exist for developers.

Styling Difficulties

Styling issues with components are one of the difficulties. The Shadow DOM separates styles from the outside world; however, applying styles to them might be difficult. To solve this problem, programmers should add content directly to their own element rather than using the Shadow DOM. Alternatively, they can apply scoped CSS styles using the :host class.

CSS custom properties (variables) are an additional helpful tool for decorating Web Components. Developers can define a variable in an outer container and utilize it within the custom elements since custom properties can cascade into Web Components. Another way to decorate an inner component with a part attribute is to use shadow parts.

Ignored Inputs

Any <input>, <textarea>, or <select> fields in the Shadow DOM are not automatically connected with the containing form. This is another problem with Web Components. Early adopters of Web Components might include hidden fields in the page’s DOM or alter values through the FormData interface.

What Are the Advantages of Using Web Components?

Web developers can benefit from using these components in a number of ways. First and foremost, they encourage code reuse both inside and outside of a project, which streamlines the organization of the program and speeds up development. Second, components are encapsulated, which means they are separate from the rest of the application’s code. This eliminates conflicts and makes the code more straightforward, well-structured, and modular. These two characteristics boost efficiency, which is crucial in today’s cutthroat marketplaces where minimizing developer effort is crucial.

Components also have the advantage of being framework agnostic, which means they may be used with any framework, such as React, Vue, and Angular, or even no framework at all. They are simpler to share and reuse because of their versatility, especially when working on projects involving several technological stacks. They are a dependable and effective solution since they employ native HTML element standards, CSS, and JavaScript frameworks and have native compatibility with contemporary browsers.

The ability to connect particular custom parts without bringing in complex dependencies gives components another edge in terms of dependencies. Due to this important distinction from well-known frameworks, components are a quick and effective solution for web development or app development.


Web components have many benefits for web development, such as reusability, encapsulation, productivity, framework independence, HTML standardization, simplicity in sharing and reuse, and lack of complex dependencies. Developers can make the program’s structure relatively simpler, and speed up the development process by employing the same component in several projects.

However, web components have significant drawbacks, such as styling issues and disregarded inputs. Maintaining styling can be challenging since some inputs in the Shadow DOM are not always connecting to the containing form. Best practices, such as avoiding the Shadow DOM, using host classes, custom properties, shadow parts, and handing in styles as attributes, are useful to overcome these difficulties.


What Is a Component in Ext JS?

In Ext JS, a component is a modular, reusable UI element that combines data, presentation, and behavior.

What Are the Features of Ext JS?

Ext JS features include robust theming, built-in UI components, a responsive layout system, powerful data management, and rich charting capabilities.

What Are the Powerful Parts of the Ext JS Framework?

The data package, component architecture, and theming system of the Ext JS framework are its most potent features.

Why Use Web UI Elements?

Web UI Elements include benefits including ease of sharing and reuse, no complex dependencies, productivity, encapsulation, and framework independence.

How Do I Use UI Components?

You can create UI components as custom elements and use them as a tag in your HTML documents to leverage UI components.

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