What is react-fiber ?
React Fiber is an internal reimplementation of the way React works under the hood. It's designed to make React more flexible and efficient, especially for large and complex applications.
Think of React like a chef in a kitchen cooking a meal. When React works on updating your app's UI, it's like the chef preparing ingredients and cooking the dish. Previously, React worked like a chef who couldn't pause cooking once they started. They had to finish cooking a dish before they could start another, even if something more urgent came up. This could lead to delays and inefficient use of resources.
With React Fiber, the chef can now pause cooking one dish if something more urgent comes up, like if a new order comes in or if an ingredient is running out. Then, the chef can quickly switch to another dish or handle the new order without wasting time.
In the context of React, this means that React Fiber allows React to pause and prioritize updates more effectively, leading to smoother and more responsive user interfaces.
Here's a simple example to illustrate React Fiber:
Let's say you have a social media app with a feed of posts. Each post has comments that users can interact with. When a user likes a comment, React needs to update the UI to reflect the new number of likes.
Without React Fiber:
- If a user likes a comment while React is updating the UI, React might wait until it's finished updating everything before it updates the number of likes. This delay could make the app feel sluggish or unresponsive.
With React Fiber:
- If a user likes a comment while React is updating the UI, React Fiber can pause the current update, quickly handle the like action, and then resume updating the UI. This makes the app feel more responsive, even during busy times.
In summary, React Fiber helps React prioritize and handle updates more efficiently, resulting in smoother and more responsive user interfaces, especially in large and complex applications.
How the terms Reconciliation and Virtual DOM are connected with react-fiber and also explain these terms ?
Reconciliation
Reconciliation is the process through which React updates the UI to match the current application state. When something changes in your React application (like user input or data updates), React determines what needs to change in the UI and efficiently updates only those parts.
For example, if a user clicks a button that triggers a change in the application state, React needs to figure out what parts of the UI need to be updated to reflect this change. Reconciliation is the process where React compares the previous state of the UI with the new state and computes the minimal set of changes needed to update the UI accordingly.
Virtual DOM
The Virtual DOM is a concept in React where a lightweight representation of the actual DOM (Document Object Model) is kept in memory. This virtual representation mirrors the structure of the real DOM but is much faster to manipulate. When changes occur in the application, React first updates the Virtual DOM rather than directly manipulating the real DOM.
For example, when you write JSX in your React components, you're essentially creating a virtual representation of the UI. React then compares this virtual representation with the previously rendered virtual DOM to determine what changes need to be made.
Connection to React Fiber
React Fiber is a reimplementation of React's core algorithm designed to improve its ability to handle complex and asynchronous updates. It's called "Fiber" because it represents the individual units of work (like the fibers in a thread) that React can pause, prioritize, and rearrange as needed.
React Fiber enhances React's reconciliation process by allowing it to pause and resume work, change priorities dynamically, and handle updates more efficiently. This capability is crucial for creating smoother and more responsive user interfaces, especially in applications with a lot of dynamic content or complex interactions.
In summary, React Fiber, reconciliation, and the virtual DOM are all interconnected parts of how React manages and updates the UI. React Fiber provides the infrastructure for React to perform reconciliation efficiently, while the virtual DOM serves as a lightweight representation of the UI that React uses during the reconciliation process to compute and apply the necessary changes to the real DOM.