JavaScript / React Native / React

Comparing the DOM in Traditional Web Development and React Native's Component Tree

April 17, 20243 min read
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Comparing the DOM in Traditional Web Development and React Native's Component Tree

The DOM in traditional web development and the component tree used in React Native are fundamentally different in how they are structured and managed, reflecting the distinct environments they operate within—browsers for the traditional DOM and mobile platforms for React Native. Here’s a breakdown of the key differences:

1. Nature of the DOM vs. React Native's Component Tree

  • Traditional DOM: The Document Object Model (DOM) is a tree-like structure that represents the HTML elements of a webpage in the browser. It allows JavaScript to access and manipulate HTML elements to dynamically change styles, content, and structure. The DOM is heavy and can be slow to manipulate due to its complexity and the dynamic nature of HTML.

  • React Native Component Tree: React Native does not use the traditional DOM. Instead, it utilizes a component tree that is an abstraction similar to the Virtual DOM used in React. This tree is made up of React components, which are ultimately translated into native UI components on iOS and Android, not HTML elements.

2. Rendering Process

  • Traditional DOM Rendering: In web development, when you manipulate the DOM (e.g., changing an element's style or content), these changes are reflected directly in the web browser. Frequent DOM manipulations can lead to performance issues due to reflows and repaints, where the browser recalculates element positions and redraws them on the screen.

  • React Native Rendering: In React Native, JavaScript runs in a separate thread and communicates with the native platform via a bridge. When a React component’s state changes, React Native updates the component tree and sends a batch of changes to the native side, where they are translated into native UI updates. This process is optimized to reduce the performance impact of updates.

3. Element Types

  • HTML Elements: In traditional web development, the elements are HTML tags like <div>, <span>, <img>, etc. These are standardized elements that browsers are designed to display.

  • Native Components: React Native uses components that correspond to native UI elements, such as <View>, <Text>, <Image>, etc. These components map directly to native platform-specific UI components (like UIView in iOS and android.view in Android).

4. Styling

  • CSS in Traditional DOM: Styling in traditional web applications is done using CSS, which directly styles HTML elements. CSS provides features like pseudo-classes, animations, and media queries.

  • Styling in React Native: React Native uses a JavaScript object-based styling system that closely resembles CSS but does not support all its features. Instead of using CSS, styles are applied using the style prop on components, leveraging a subset of CSS properties.

5. Performance Considerations

  • Traditional DOM: Manipulating the DOM can be slow and inefficient if not handled carefully, especially with complex applications that require frequent updates.

  • React Native: By abstracting the actual rendering to native components and minimizing bridge communication, React Native aims to offer smoother performance on mobile devices, making it more suitable for creating complex and performance-sensitive mobile applications.

In summary, while both systems create user interfaces, the traditional DOM is a more general and less optimized approach for dynamic web content, whereas React Native provides a more specialized and performance-optimized method tailored for mobile app development by leveraging native components.

JavaScriptReact NativeDOMComponent Tree