CLASS 32
Custom Hooks
REVIEW, RESEARCH AND DISCUSS
What does a component’s lifecycle refer to?
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Each component in React has a lifecycle which you can monitor and manipulate during its three main phases. The three phases are:
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mounting -
updating -
unmounting
Why do you sometimes need to “wrap” functions in useCallback when called from within useEffect
- useCallback will help in avoiding regeneration of functions when the functional component re-renders. However there isn’t much of a performance difference caused by recreation of functions.
Why are functional components preferred over class components?
- Functional component are much easier to read and test because they are plain JavaScript functions without state or lifecycle-hooks.
TERMS:
state hook
or useState() allows you to use state and other React features without writing a class. Hooks are the functions which “hook into” React state and lifecycle features from function components.
effect hook
or useEffect() tells your component needs to do something after render. React will remember the function you passed, and call it later after performing the DOM updates.
reducer hook
or useReducer() is usually preferable to useState when you have complex state logic that involves multiple sub-values or when the next state depends on the previous one.