Just wasted my whole day yesterday developing a complex people search box at my job. Had to learn all this the hard way 😅 If only you'd posted this a bit sooner 😆
Me too. I was proud of myself, thinking 'I completely dominate forms in React'. But Kyle proved me wrong, and I'm thankful for that. Plus, I learned how to use useRef and useMemo (might have to read more about it to fully understand it), but overall, this was a very useful video.
One small thing I'd add to the top of the useMemo -> if (!query) return items So you don't iterate over the whole list of items if there is no query Important for large lists, and also use debouncing in large lists
This is a sort of hack but for this specific situation the best way is actually to hide the items using css attribute selectors :P then hide them with [data-search*=""] { display: none } Obviously this is an over simplification but works for very large lists
@@nguyenduy-sb4ue Why would it be messed up? It accomplishes the task without super expensive rerenders or DOM manipulation at all. If you have a list of 10,000 nodes removing those from the DOM tree is extremely expensive especially since it blocks the entire thread. Utilizing the browser's much faster css engine would be tens of times faster
@@agenticmark no shit sherlock, that's the point. Everyone knows React sucks at rendering large arrays that's why we sometimes have to use "hacks". Or tricks to get around its limitations
Nice video mpan, but to me, it's still not the most efficient way to do it because you're still storing the filtered array. Instead, you can just filter the items array directly in the render() right after the map function. Tell me if I'm missing something.
I've learned a lot from this guy since I subscribed from this channel. I always looked back from his video list whenever I got stuck from coding. Thank you man.
I don't know why, but almost every time I watch your "most people do it wrong" videos, I realise that I've been doing the given thing correctly despite the fact that I've learned React on my own through experimentation. Nevertheless, I love watching them just to confirm that there's no better approach. Great work, man, keep it up!
4:30 you can extract input value without using ref either by accessing form elements like this: console.log(e.target.elements.inputElementName), or by extracting formData like this: const data = FormData(event.target); console.log(data.get("inputElementName")); Both require you to assign the name to your input element, though.
Hey! Thanks, Kyle I was confused in my react project about adding filtration and this video solved it perfectly... Thanks really .... You mentioned that you have a free react course right? Now I'm gonna check that as well... I learned a lot...Thanks.
The third way was what i was doing from the beginning of my react learning. I thought this is how people do it because it made sense if a state changes a component rerenders so storing the input value in state makes your component rerender thus storing the filtered value in a regular variables works just fine.
Key takeaway (which is also stressed in the react docs): don't duplicate state. It is extremely rare for state needing to be duplicated (ie. the same data appearing in different states, or multiple times within the same state). The memoization is a nice addition and good to be aware of, but the docs recommend against preemptive optimizations. If you do optimise, you should keep in mind the memory footprint of that memo and most importantly whether the memo tends to be used (versus a component whose primary state changes involve changing one of the dependencies of the memo)
Hi, great video. But do you agree that react is only suitable for (very) senior devs, since there are soooo many code ‘design’ mistakes to make? As a project manager with dev skills, I just don’t dare to start a react project due to this complexity for an enterprise client.
A very good video. I love your content, they are simple and easy to understand. I love those contents were it's explained why it is not correct or vice-versa. Best regards
Have you considered switching to Vite in your future tutorials? CRA is no longer the best way to make very lightweight SPAs. You can look up videos on why that’s the case for most uses
It never was the best way to make lightweight SPA's, it was intended as a learning tool and for that it still serves its purpose (though you'd be right to point out that vite is largely just as beginner-friendly as CRA and can easily serve the same purpose, in addition to being production-friendly). That said, it would be nice for him to at least address vite and the problems with using CRA on any project that isn't just for learning.
The big problem here is that you're constantly iterating through an array for each change you make. In the real world, you're getting data from a backend upon request, so it's much more effective to just type your query and then make the request for the data so you only receive what you asked for instead of working with large chunks on FE.
Thank you, explanations are really good ! Maybe you could explain a bit more the custom hooks / useEffect concept, which is not the easiest to understand ?!
Hey kyle, can we not directly nest the filter function just before mapping the list, is it a bad approach? I’m doing this since 1 year in my company’s project 😅
Quick tip: You don't need to write return if you wrap function body in parentheses. So instead doing this: filteredItems = items.filter(item => { return item.toLowerCase()... }) You can do this: filteredItems = items.filter(item => (item.toLowerCase()... ))
You don't even need the parenthesis here because you're returning a single value. This is called implicit return. You would only need parentheses if you were returning an object, for example, items.filter( item => ({ foo: bar }) ).
Super useful.... I was just working on the filters last day.... And i used the first approach.... And now you taught me the correct method.... Thanks buddy ♥️
Another bug with the second naive approach is that if you add a new item, because you're calling "setFilteredItems", the new item will be added to your list even if you have a search term that filters it out. So if your search bar had "on", but you added "three", your list would become "one, three" until you modified the search query again, at which point it would get filtered out correctly.
I've been learning react for about a year now. I've just now gotten my first large scale app 99.9% done. I sure wish I had known about useRef 6 months ago :(
I love your video, but I am struggling to add debouncing of the filter ? (using the debounce hook of your courses). I see no other way than using useState for filteredProduct, or maybe there is away to use the custom hook useDebouce with useMemo ??? edit : by using your custom hook usedebounce, i mean, create another one but for useMemo xD not using useefecct behind lol
Really informative video also I have a question is it good to just a const like filteredItems because I have also seen people saying let react handle the state so would it be fine to keep the filteredItems inside a useState Sorry my English is not that good
Man, you are a genius programming - Thank you so much for the tutorial. It helped me a lot. a tip for everyone. {query ? setFilteredItems.map((item) => { return ("your components and etc") : null } It will display the list only when the user starts typing.
Very helpful as always... One quick question for anyone who could answer: Is it best practice, mandatory or irrelevant split your "fetch code" from your rendering component?! Thanks!!!
I would say yes. By separating them you can extend them independently like adding caching, retries or multiple sources without touching the rendering component OR switch rendering or render in more than one place or ... there are so many possible reasons you would want to do it :) And when you do, you also might want to separate out state from the actual display components, but that is a bit more nuanced.
Just don't use CRA, even if he does. There's Vite now, it's 2022. CRA made sense bc of the polyfills and bc no one wanted to set up a react env and configure webpack by hand. Now it's just a bloated and buggy piece of sh*t.
So in this particular situation the function version was used to get the previous value of the items state variable and then a filter was performed in that function. If your new value of a state is being derived from the previous value of that state you should always use the function version to pipe in the value instead of accessing it directly. so do this setCount(prevCount => prevCount + 1) and not this setCount(count + 1) and once he had removed the filtering function to it's own slice of state he no longer needed to access the previous version of the items state inside its own setState function so just using the state variable was fine
I handle this problem by storing the state of the items in an object in the list. When something is typed, i change the state of the object of the item, it is shown or not.
Still better have a query request to receive the filtered list from a server and not doing it from the front, it can be very costly in terms of performance when the list is long.
One thing to notice is that, the cost of recalculate filteredItems is not that much, but the cost of re-render filteredItems into the tree is much more bigger
@@khoinguyen-ft2ys Ahh...the blog post which you cited also addressed the same thing as my link above: "Unnecessary re-renders by themselves are not a problem: React is very fast and usually able to deal with them without users noticing anything" Therefore, most of the time, it's more likely the issue of slow render rather than Unnecessary re-render. Anw, tysm for such an in-depth article, I'm very glad that I learnt something new after all :D
Great video as usual. Is there any reason you are using an uncontrolled form? Facebook recommends use of controlled forms instead of uncontrolled forms. Just curious?
So think of a react component as just a simple function call, each time the component re-renders it is a brand new function call. So every time the component is re-rendered all the code inside the function is re-ran, any plain variables (even constant variables) are re-calculated on each call. That was one of the main driving points to the creation of React state and refs, to preserve data between renders (function calls)
@@agenticmark I'm not sure what this reply is supposedly to do with my comment. Using refs to preserve data across function calls? that is literally what refs are used for.
Thank you so much, Kyle, your contents are always excellent, I have learnt so much and am grateful. I am curious though, instead of using a useMemo, why not just have a use effect that filters the items, with items and queries in the dependency array, I think the question is, which is better? because useMemo sure comes with a cost.
useMemo is like a useState with dependencies automaticly triggering it. If you useEffect, you'd need to create a new useState to save the filtered items (if you modify a const of an array set in code it won't work because useEffect runs after the render, it wouldn't render the updated const array).. thus with useEffect/useState, 2 re-renders: one setQuery/setItems changes -> triggers -> useEffect -> triggers -> setFilteredList (which by setting a new state triggers a re-render a second time to display the updated filteredList state). Using useMemo will do the same in only one re-render, because it sets the 'returned state of useMemo' before rendering, not after. useEffect runs after the component has re-rendered.
Currently learning React, so apologies if there's something I'm not catching about how useMemo works, but wouldn't this end up using much more memory than just "duplicating" the state, especially if it fires off for every letter typed? Isn't this just hiding that under an abstraction effectively making it harder to reason about if there ever is an issue?
Answer to myself: okay so useMemo is about persisting results through rerenders when their dependencies haven't changed, so there won't be an unknown size of growing cache of previous calculations, just a persistence of the last one to avoid recalc on every render. It's effectively useState with some magic on top to abstract it away as derived state. Learning by asking, and then looking it up 😅
Does this also work for when getting data from a DB. I've always made a filter method in my backend code. Then when you type in a search box you call the API filter method and get the returned code. I've always thought this a little crazy, as you could be making several API calls. This way makes perfect sense if your array is already in state in your react app. I've just made an app using redux state management so I presume you can use a similar approach here?
Debounce the input so you don't trigger on every key press and cache the result from API. The cache rules are set by the API server. If no cache headers exist or if it explicitly says not to cache, you can still cache it locally using Redux, sessionStorage or just a JavaScript Map.
The inputRef is also unnecessary. If you name the form inputs you'll be able to access them straight through the event.target, which will be our form in the SubmitEvent. For example, if the input is named searchInput, we can access the DOM element by using event.target.searchInput.
useEffect triggers a function if something changes. useMemo just saves all values returned within it, and uses the stored values instead of running a function to figure it out again.
One mistake I've learned is that I continuously fire API or filters items on input change, so, it's better to add debounce function, wait until the typing is finished and fire API or filter.
You do not need ref to get value from Input. e.target.value is enough. And never set value ref.current.value. You should just say setValue(‘’) as it is controlled input.
Like every other turorial out there, this is nice for small projects for learning react or small scale personal websites. Id like to see a server sided pagination with filters tutorial. I think that would be very useful
Hi Kyle, do you mentor those who purchase your courses if they have problems or questions? Like a discord group or something? Love the way you take your lessons but I would really love to have some mentoring as well while I learn React. Thanks
Just wasted my whole day yesterday developing a complex people search box at my job. Had to learn all this the hard way 😅 If only you'd posted this a bit sooner 😆
Now, your mind and body will never forget how to make a search box for the rest of your time
You can just use react-select library for search input select field. Amazing library
You only wasted a day. Those are rookie numbers in this bracket
Yeah ! Kyle is a real a hole ! Kidding ofc ! Amazing content !
...? What lamo
Very helpful! I was actually doing mistake #2 in a recent project, but now I know that I'll have to change that :D
Me too. I was proud of myself, thinking 'I completely dominate forms in React'.
But Kyle proved me wrong, and I'm thankful for that. Plus, I learned how to use useRef and useMemo (might have to read more about it to fully understand it), but overall, this was a very useful video.
One small thing I'd add to the top of the useMemo -> if (!query) return items
So you don't iterate over the whole list of items if there is no query
Important for large lists, and also use debouncing in large lists
top 10 mistakes a clickbaiter makes when viewer fkin his mom [DO NOT MAKE THIS MISTAKE YOURSELF!]
true! small but awesome observation
But then again, you don't want to have large lists as you'll use server side pagination
@@parlor3115 It depends, really. Sometimes I will use large lists that are generated on the client side.
isn't that redundant with useMemo and depende. array?
My guy’s about to get cancelled for using CRA in 2022 😅
Thanks brother. I am learning react now. Hoping to see me coding like you soon in few years.
This is a sort of hack but for this specific situation the best way is actually to hide the items using css attribute selectors :P
then hide them with [data-search*=""] { display: none }
Obviously this is an over simplification but works for very large lists
What ? That is super mess up
@@nguyenduy-sb4ue Why would it be messed up? It accomplishes the task without super expensive rerenders or DOM manipulation at all. If you have a list of 10,000 nodes removing those from the DOM tree is extremely expensive especially since it blocks the entire thread. Utilizing the browser's much faster css engine would be tens of times faster
@@agenticmark no shit sherlock, that's the point. Everyone knows React sucks at rendering large arrays that's why we sometimes have to use "hacks". Or tricks to get around its limitations
Nice video mpan, but to me, it's still not the most efficient way to do it because you're still storing the filtered array. Instead, you can just filter the items array directly in the render() right after the map function. Tell me if I'm missing something.
I've learned a lot from this guy since I subscribed from this channel. I always looked back from his video list whenever I got stuck from coding. Thank you man.
I just finished going through the entire React documentation and this is the best video for me to get started on a new project with React! Thanks Kyle
Now you'll get to build your dream project sooner
@@parlor3115 lol
I don't know why, but almost every time I watch your "most people do it wrong" videos, I realise that I've been doing the given thing correctly despite the fact that I've learned React on my own through experimentation. Nevertheless, I love watching them just to confirm that there's no better approach. Great work, man, keep it up!
Fr
☝🤓
@@srpatata4172 🤓🤘!
4:30 you can extract input value without using ref either by accessing form elements like this: console.log(e.target.elements.inputElementName), or by extracting formData like this: const data = FormData(event.target); console.log(data.get("inputElementName"));
Both require you to assign the name to your input element, though.
Why do we need a state for query, wouldn't it be simpler to just do the filtering in the onChange event and just grab the value there?
Hey! Thanks, Kyle I was confused in my react project about adding filtration and this video solved it perfectly... Thanks really .... You mentioned that you have a free react course right? Now I'm gonna check that as well... I learned a lot...Thanks.
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I am really grateful for all the content, thanks Kyle!
The third way was what i was doing from the beginning of my react learning. I thought this is how people do it because it made sense if a state changes a component rerenders so storing the input value in state makes your component rerender thus storing the filtered value in a regular variables works just fine.
Key takeaway (which is also stressed in the react docs): don't duplicate state. It is extremely rare for state needing to be duplicated (ie. the same data appearing in different states, or multiple times within the same state). The memoization is a nice addition and good to be aware of, but the docs recommend against preemptive optimizations. If you do optimise, you should keep in mind the memory footprint of that memo and most importantly whether the memo tends to be used (versus a component whose primary state changes involve changing one of the dependencies of the memo)
Ever since I started watching this channel, my react skills are improving. thanks man
Hi, great video. But do you agree that react is only suitable for (very) senior devs, since there are soooo many code ‘design’ mistakes to make? As a project manager with dev skills, I just don’t dare to start a react project due to this complexity for an enterprise client.
Thank you, I'm doing my first mini-project and it helped me a lot
A very good video. I love your content, they are simple and easy to understand. I love those contents were it's explained why it is not correct or vice-versa. Best regards
Have you considered switching to Vite in your future tutorials? CRA is no longer the best way to make very lightweight SPAs. You can look up videos on why that’s the case for most uses
I'm a few weeks into react, and I keep seeing youtubers also saying not to use CRA lol. Might have to look into Vite as well. Thanks for the heads up!
It never was the best way to make lightweight SPA's, it was intended as a learning tool and for that it still serves its purpose (though you'd be right to point out that vite is largely just as beginner-friendly as CRA and can easily serve the same purpose, in addition to being production-friendly). That said, it would be nice for him to at least address vite and the problems with using CRA on any project that isn't just for learning.
His ears must have been burning bc he just released a video about using Vite instead of CRA.
@@ontheruntonowhere that doesn’t mean his ears are burning or smth, he just realized he was wrong and that’s good
@@PatrikTheDev It's a figure of speech dude. Doesn't mean he was wrong.
Hey Kyle great video as always, you could possibly show how to do this with async data too.
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Thank you, Kyle. Great video as usual!
What are your thoughts on using Vite instead of CRA, I find it so much faster to install and run
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Correct me if I am wrong. That "items" inside useMemo deps is an array so its render everytime no?
Because state isn't recreated on each render putting items in a dep array is perfectly fine ( and really the most elegant solution)
Hey Kyle could you do a video on the new react update that has changes to async await with promises?
THIS VIDEO CAME IN THE RIGHT TIME, THANK YOU SO MUCH YOU'RE THE SIMPLEST ON RUclips
thanks a lot !
We need another video for node js developers
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The big problem here is that you're constantly iterating through an array for each change you make. In the real world, you're getting data from a backend upon request, so it's much more effective to just type your query and then make the request for the data so you only receive what you asked for instead of working with large chunks on FE.
Thank you, explanations are really good !
Maybe you could explain a bit more the custom hooks / useEffect concept, which is not the easiest to understand ?!
Nice, but you don’t need a ref. You can take input value from the event in the handle submit.
Thanks for explaining that. I saw the correct way a couple of times but didn't really understand why we need to do it that way.
moral of the story every string includes empty string.
Caching was happening because you forgot to add the key in map element render.
Hey kyle, can we not directly nest the filter function just before mapping the list, is it a bad approach?
I’m doing this since 1 year in my company’s project 😅
Thought using ref like that wasn't right. You're supposed to manage your form fields
Quick tip: You don't need to write return if you wrap function body in parentheses.
So instead doing this:
filteredItems = items.filter(item => { return item.toLowerCase()... })
You can do this:
filteredItems = items.filter(item => (item.toLowerCase()... ))
You don't even need the parenthesis here because you're returning a single value. This is called implicit return. You would only need parentheses if you were returning an object, for example, items.filter( item => ({ foo: bar }) ).
@@ridiculousgames365 Yeah, you are right.
Please make videos on node js and express more. We need updated and advanced topics covered in those videos. Thanks 🙏👍🏻
Super useful.... I was just working on the filters last day.... And i used the first approach.... And now you taught me the correct method.... Thanks buddy ♥️
Another bug with the second naive approach is that if you add a new item, because you're calling "setFilteredItems", the new item will be added to your list even if you have a search term that filters it out. So if your search bar had "on", but you added "three", your list would become "one, three" until you modified the search query again, at which point it would get filtered out correctly.
I've been learning react for about a year now. I've just now gotten my first large scale app 99.9% done. I sure wish I had known about useRef 6 months ago :(
I love your video, but I am struggling to add debouncing of the filter ? (using the debounce hook of your courses).
I see no other way than using useState for filteredProduct, or maybe there is away to use the custom hook useDebouce with useMemo ???
edit : by using your custom hook usedebounce, i mean, create another one but for useMemo xD not using useefecct behind lol
Really informative video also I have a question is it good to just a const like filteredItems because I have also seen people saying let react handle the state so would it be fine to keep the filteredItems inside a useState
Sorry my English is not that good
I hardly can think of use cases for such iten lists. If you do not store them in a database, what good will they do to you?
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Thankyou
After watching WDS tutorials I am able to write React code. Thanks man!!! Very much appreciated.
Why use state for query when you can useRef() ?
Thanks for the video!
This is the first time I have seen this kind of video and realize I do it the right way 😅
Same lol this was a pleasing confidence boost for once 😂
Thanks a lot
Such a simple use case, but still so many wrong techniques to implement a search bar. Thanks for making such videos
thank you kyler for this video, it's really helpful
Can you do one on how to implement remote pagination with react
Hello web dev simplified, can you teach us how to set up and install react fully, in Vs code.
Man, you are a genius programming - Thank you so much for the tutorial. It helped me a lot.
a tip for everyone.
{query ? setFilteredItems.map((item) => { return ("your components and etc") : null } It will display the list only when the user starts typing.
Very helpful as always...
One quick question for anyone who could answer:
Is it best practice, mandatory or irrelevant split your "fetch code" from your rendering component?!
Thanks!!!
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I would say yes. By separating them you can extend them independently like adding caching, retries or multiple sources without touching the rendering component OR switch rendering or render in more than one place or ... there are so many possible reasons you would want to do it :)
And when you do, you also might want to separate out state from the actual display components, but that is a bit more nuanced.
learning React rn in school and i learn more from you than them
Just don't use CRA, even if he does. There's Vite now, it's 2022. CRA made sense bc of the polyfills and bc no one wanted to set up a react env and configure webpack by hand. Now it's just a bloated and buggy piece of sh*t.
@@EnriqueDominguezProfile oh cool, thanks! I’ll look into Vite.
Can't understand if query is " " then why in filter items we are getting all data of item.filter it should return [] ?
Why does he not need the function version anymore at 8:00 ? Why was it needed at all?
So in this particular situation the function version was used to get the previous value of the items state variable and then a filter was performed in that function. If your new value of a state is being derived from the previous value of that state you should always use the function version to pipe in the value instead of accessing it directly.
so do this
setCount(prevCount => prevCount + 1)
and not this
setCount(count + 1)
and once he had removed the filtering function to it's own slice of state he no longer needed to access the previous version of the items state inside its own setState function so just using the state variable was fine
I handle this problem by storing the state of the items in an object in the list. When something is typed, i change the state of the object of the item, it is shown or not.
why not use filter with the query before map like this,
items.filter(item => item.toLowerCase().includes(query.toLowerCase())).map(..........)
Unnecessary overhead while rendering. Makes performance terrible for long lists.
Still better have a query request to receive the filtered list from a server and not doing it from the front, it can be very costly in terms of performance when the list is long.
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no way you just called me naive and bad code writter :c but I learn something, so we cool
Thank you a lot . Good stuff
One thing to notice is that, the cost of recalculate filteredItems is not that much, but the cost of re-render filteredItems into the tree is much more bigger
@@khoinguyen-ft2ys Ahh...the blog post which you cited also addressed the same thing as my link above:
"Unnecessary re-renders by themselves are not a problem: React is very fast and usually able to deal with them without users noticing anything"
Therefore, most of the time, it's more likely the issue of slow render rather than Unnecessary re-render.
Anw, tysm for such an in-depth article, I'm very glad that I learnt something new after all :D
@@RandomGuy-jv4vd You're welcome
Great video as usual. Is there any reason you are using an uncontrolled form? Facebook recommends use of controlled forms instead of uncontrolled forms. Just curious?
Helpline 📲📩⬆️
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Fantastic tutorials. Thanks!
const filteredItems, but its actually not a constant, is it ok to do in React, or am i missing something?
So think of a react component as just a simple function call, each time the component re-renders it is a brand new function call.
So every time the component is re-rendered all the code inside the function is re-ran, any plain variables (even constant variables) are re-calculated on each call.
That was one of the main driving points to the creation of React state and refs, to preserve data between renders (function calls)
@@agenticmark I'm not sure what this reply is supposedly to do with my comment.
Using refs to preserve data across function calls? that is literally what refs are used for.
Stuff for beginners)) Perfect result in the end!
I like your videos, but the clickbait titles into 10 minutes of setup before we actually hear what the topic is is kind of irritating.
Thank you so much, Kyle, your contents are always excellent, I have learnt so much and am grateful. I am curious though, instead of using a useMemo, why not just have a use effect that filters the items, with items and queries in the dependency array, I think the question is, which is better? because useMemo sure comes with a cost.
useMemo is like a useState with dependencies automaticly triggering it. If you useEffect, you'd need to create a new useState to save the filtered items (if you modify a const of an array set in code it won't work because useEffect runs after the render, it wouldn't render the updated const array)..
thus with useEffect/useState, 2 re-renders: one setQuery/setItems changes -> triggers -> useEffect -> triggers -> setFilteredList (which by setting a new state triggers a re-render a second time to display the updated filteredList state). Using useMemo will do the same in only one re-render, because it sets the 'returned state of useMemo' before rendering, not after. useEffect runs after the component has re-rendered.
"Most Beginner React Developers Do This Wrong"
Using cra to start a project...
How is the approach for adding a bool variable like visible to display filtered content or not .
@Kyle why did we not wrap the search input inside a form?
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but... you said we shouldn't be using RCA... why not vite?
Pretty informative, thx
its crazy to see how ugly reacts code is compared to vue's code, like it's total mess and even vanilla js looks better.
Super useful
Good stuff!
this is weird,can someone tell me why there are items in filteredItem variable if condition is not matched in filter fn?
Currently learning React, so apologies if there's something I'm not catching about how useMemo works, but wouldn't this end up using much more memory than just "duplicating" the state, especially if it fires off for every letter typed? Isn't this just hiding that under an abstraction effectively making it harder to reason about if there ever is an issue?
Answer to myself: okay so useMemo is about persisting results through rerenders when their dependencies haven't changed, so there won't be an unknown size of growing cache of previous calculations, just a persistence of the last one to avoid recalc on every render. It's effectively useState with some magic on top to abstract it away as derived state.
Learning by asking, and then looking it up 😅
👍👍
Hello Kyle I thnk there's another better way
thank you bro, you're awesome!!!!
Amazing! I'm learning sooo much with your videos! Thank you!
Does this also work for when getting data from a DB. I've always made a filter method in my backend code. Then when you type in a search box you call the API filter method and get the returned code. I've always thought this a little crazy, as you could be making several API calls.
This way makes perfect sense if your array is already in state in your react app.
I've just made an app using redux state management so I presume you can use a similar approach here?
Debounce the input so you don't trigger on every key press and cache the result from API. The cache rules are set by the API server.
If no cache headers exist or if it explicitly says not to cache, you can still cache it locally using Redux, sessionStorage or just a JavaScript Map.
Best tutorial for search bar thanks❤
The inputRef is also unnecessary. If you name the form inputs you'll be able to access them straight through the event.target, which will be our form in the SubmitEvent.
For example, if the input is named searchInput, we can access the DOM element by using event.target.searchInput.
Can someone explain to me shortly, what is the difference between useEffect and useMemo? I'm a beginner in react and still confused about it.
Helpline 📲📩⬆️
Questions can come in⬆️
useEffect triggers a function if something changes. useMemo just saves all values returned within it, and uses the stored values instead of running a function to figure it out again.
базар жок Кайли!Ырзамын гой
As always great videos I directly jumped to correct filtering method
One mistake I've learned is that I continuously fire API or filters items on input change, so, it's better to add debounce function, wait until the typing is finished and fire API or filter.
How to use useRef() in TypeScript with current.value?
like the one react beta doc example
You do not need ref to get value from Input. e.target.value is enough. And never set value ref.current.value. You should just say setValue(‘’) as it is controlled input.
Like every other turorial out there, this is nice for small projects for learning react or small scale personal websites. Id like to see a server sided pagination with filters tutorial. I think that would be very useful
its very helpful
Hi Kyle, do you mentor those who purchase your courses if they have problems or questions? Like a discord group or something? Love the way you take your lessons but I would really love to have some mentoring as well while I learn React. Thanks
Helpful, thanks
Man's still running Create React App in 2022 lmao