Preventing Unnecessary Child Component Rerenders
React offers various optimizations for reducing unnecessary renders in child components, one being the utilization of React’s React.memo higher-order component. This optimization strategy focuses on re-rendering a component solely when its props undergo modification. However, if a parent component consistently provides a new function instance during each render—even if the function remains unchanged—React.memo will interpret this as a prop alteration, resulting in unnecessary re-renders of the child component.
Here, useCallback assumes significance by ensuring the preservation of the same function instance across renders. By maintaining consistency in function references, useCallback mitigates the risk of React.memo and similar optimizations in child components misinterpreting a new function instance as a change in props. Consequently, this practice minimizes redundant re-renders, thereby optimizing performance, particularly in complex component hierarchies.
const
NestedComponet = React.memo(({ onClick }) => {
//
});
const
MainComponent = () => {
const
handleClicked = useCallback(() => {
console.log('Clicked Done!');
}, []);
return
<NestedComponent onClick={handleClicked} />;
};
Optimizing Performance with useMemo and useCallback Hooks
In React applications, optimizing performance is crucial for ensuring smooth user experiences, especially in components with complex computations or frequent re-renders. Two hooks provided by React, useMemo, and useCallback, offer efficient ways to achieve performance improvements by memoizing values and callback functions, respectively.
Table of Content
- Understanding the Need for Optimization
- Determining When to Utilize These Hooks
- useMemo: Preserving Computation Results
- useCallback: Memoizing Functions
- How useCallback works?
- Preventing Unnecessary Child Component Rerenders
- Benefits of useMemo an useCallback Hooks
- Conclusion