usecallback

Should I wrap all functions that defined in component in useCallback?

由 半世苍凉 提交于 2021-02-18 21:57:58
问题 As far as I've known, functions that defined in a React's functional component are regenerated whenever the component rerenders. Since useCallback can be triggered by specific dependencies, it prevents unnecessary regeneration of these functions. Should I wrap each of them in useCallback, and pass relevant dependencies? import React from 'react' const Comp = () => { const fn1 = useCallback( ()=>{ // do something 　　　}, [dependency1]) const fn2 = useCallback( ()=>{ // do something 　　　},

Should I wrap all functions that defined in component in useCallback?

由 删除回忆录丶 提交于 2021-02-18 21:57:40
问题 As far as I've known, functions that defined in a React's functional component are regenerated whenever the component rerenders. Since useCallback can be triggered by specific dependencies, it prevents unnecessary regeneration of these functions. Should I wrap each of them in useCallback, and pass relevant dependencies? import React from 'react' const Comp = () => { const fn1 = useCallback( ()=>{ // do something 　　　}, [dependency1]) const fn2 = useCallback( ()=>{ // do something 　　　},

is there any benefit of using useCallback without React.memo?

由 流过昼夜 提交于 2021-01-28 18:45:26
问题 From what i understood from React documentation and other material across web, useCallback is used to avoid re-rendering of child component by ensuring that memoized version of callback is passed to it, thus referentially props remain same for child component. But all this is valid only if I am using React.memo on child component. Without React.memo, child component would re-render anyways. My question is what use is useCallback in this case i.e. without React.memo applied to child component.

useLoopCallback — useCallback hook for components created inside a loop

由 若如初见. 提交于 2019-12-02 07:09:25
问题 I'd like to start a discussion on the recommended approach for creating callbacks that take in a parameter from a component created inside a loop. For example, if I'm populating a list of items that will have a "Delete" button, I want the "onDeleteItem" callback to know the index of the item to delete. So something like this: const onDeleteItem = useCallback(index => () => { setList(list.slice(0, index).concat(list.slice(index + 1))); }, [list]); return ( <div> {list.map((item, index) => <div

useLoopCallback — useCallback hook for components created inside a loop

由 不羁岁月 提交于 2019-12-02 00:56:54
I'd like to start a discussion on the recommended approach for creating callbacks that take in a parameter from a component created inside a loop. For example, if I'm populating a list of items that will have a "Delete" button, I want the "onDeleteItem" callback to know the index of the item to delete. So something like this: const onDeleteItem = useCallback(index => () => { setList(list.slice(0, index).concat(list.slice(index + 1))); }, [list]); return ( <div> {list.map((item, index) => <div> <span>{item}</span> <button type="button" onClick={onDeleteItem(index)}>Delete</button> </div> )} <
订阅 usecallback