What is useOptimistic?
useOptimistic is a React hook that enables optimistic UI updates. It provides a way to show a temporary, “optimistic” state to the user immediately after an action is taken, while the actual asynchronous operation (like a network request) is in progress. This makes the user interface feel more responsive and faster.
Optimistic updates mean:
- Immediate Feedback: When a user performs an action that triggers an asynchronous operation (like sending data to a server), you update the UI immediately as if the operation has already succeeded.
- Assumption of Success: You “optimistically” assume the operation will be successful.
- Reversion if Failure: If the asynchronous operation fails, the UI is then reverted to its previous state.
Why is it useful?
It significantly improves the user experience by:
- Making the UI feel faster and more responsive: Users don’t have to wait for a network request to complete before seeing a visual change. This creates a smoother and more engaging interaction.
- Reducing perceived latency: Even if the actual operation takes time, the instant UI update gives the impression of speed.
How it Works:
Imagine you’re sending a message in a chat application:
- User types and clicks “Send”:
- Instead of waiting for the message to be sent to the server and then appear in the chat, useOptimistic immediately adds the message to the chat display on the user’s screen. (This is the “optimistic” part).
- Message is sent to the server:
- In the background, the actual network request to send the message is happening.
- Server responds:
- If successful: The optimistic update remains as is. The user never notices any delay.
- If it fails (e.g., network error): The useOptimistic hook automatically reverts the UI, removing the message that was optimistically added. The user then knows the message wasn’t sent.
Syntax
const [optimisticState, applyOptimisticUpdate] = useOptimistic(initialState, updaterFunction);
EXAMPLE CODE
