Recently our team got hands-on with React SuspenseList for controlling load order and accumulated quite a bit of experience. I'm writing it up as a reference, hoping it helps others doing similar work.
Core Concepts
Building on this, we can optimize further:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This pattern is very useful in large projects and significantly cuts maintenance cost.
In-Depth Analysis
In real projects the usage gets a bit more complex:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This approach improves both the testability and extensibility of the code.
Implementation Experience
Here is a complete example:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
Pay attention to edge-case handling—it is critical in production.
Tuning Strategies
The key is understanding the core logic:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
Performance optimization has to be tuned to the actual scenario—not everything needs over-optimization.
Important Notes
We can improve it in the following ways:
import { useReducer, useCallback } from 'react'
const initialState = { items: [], filter: '', sort: 'date' }
function reducer(state, action) {
switch (action.type) {
case 'SET_ITEMS': return { ...state, items: action.payload }
case 'SET_FILTER': return { ...state, filter: action.payload }
case 'ADD_ITEM': return { ...state, items: [...state.items, action.payload] }
case 'REMOVE_ITEM': return { ...state, items: state.items.filter(i => i.id !== action.payload) }
default: throw new Error(`Unknown: ${action.type}`)
}
}
This approach has been running stably in production for over half a year and is proven in practice.
Summary
- Don't adopt new tech just for its own sake.
- The code examples are for reference only; adapt them to your use case.
- React SuspenseList for controlling load order isn't a silver bullet—pick it based on project size and tech stack.
- Understanding the underlying principles matters more than memorizing APIs.
