is performace degraded if we use jquery with reactjs?
because jquery changes directly DOM elements where as reactjs works with Virtual DOM.
is there any example reactjs with jquery?
is performace degraded if we use jquery with reactjs?
Not necessarily.
because jquery changes directly DOM elements where as reactjs works with Virtual DOM.
You are correct that jQuery does not utilize React's virtual DOM. Aside from rewriting core parts of jQuery to utilize it, vanilla jQuery will not. A wrapping component that does participate in React's virtual DOM can patch it in though.
The performance of this entirely depends on your usage. Keep in mind that React does still manipulate the DOM at the end of the virtual DOM work.
You can find the most up to date, official example at the Use React with Other Libraries page of the official React docs but it is admittedly light on the details.
is there any example reactjs with jquery?
If you check out this unit of react-training on wrapping DOM[-manipulating] libraries you can find a beautiful, comprehensive example of using ReactJS with both jQuery and jQuery UI.
Using the result of that article as a baseline, you will be using jQuery at time of React's initial mount time to minimally to do the DOM work and provide classnames for styling as needed, and React's pre-render props changing lifecycle event to re-render from changes through React. You are obviously free to use other events, such as shouldComponentUpdate or manually triggering renders as well, as your needs dictate.
Your performance will largely be tied to what you do in that re-render step.
Here are some tips that may help stave off some common performance vampires:
Ensure you are caching selectors and functions wherever possible
Ensure collection member's identities are properly keyed so that they aren't resulting in constant cache misses and thus constant re-renders
Especially if you are using unidirectional data flows or immutable data stores.
Some mapping operating always return new objects and so need extra care or a different api call.
Aside from that, keeping in mind both React best practices and jQuery best practices will take you a long way.
At the end of the day it's just JavaScript - React tries to keep away unnecessary heavy true DOM object creation/manipulation where jQuery allows misusing it just fine - but there is nothing by its nature to prevent making a performant jQuery app.
Related
I'm fairly new to react; just learning it. From what I understand react gives you ability to render data more dynamically. But couldn't this be achieved using flask rest api endpoints? Kind of making AJAX calls and rendering it's response dynamically?
What's the difference?
I'm currently trying to develop a full stack application. Trying to choose what I should use for frontend, typically on a normal day I tend to use pure HTML/CS/JS to accomplish most of my front-end task without having to use JS libraries such as react to render data dynamically, I want to improve my ways around handling front-end stuff hence wanted to learn more about react and how it can benefit me; before actually diving in it.
What can help is; if someone can lay it out for me; describing work scenario using reactjs and how I can be benefiting from using the js library.
Thanks.
In my opinion, React is all about how effectively you can render your dom elements.
Rendering DOM (Painting your webpage with your HTML elements) is considered to be one of the costliest operation. And if you consider using other libraries( apart from react), there is a chance that your HTML will be rendered even if it doesnt change.
Here comes the power of React. React uses the concept of Virtual DOM which helps in rendering HTML to browser only when there is a change. For example, if you have a list of items being displayed, and if one list item changed because of some action, React will trigger a change to render only that element(of course we write very minimal code for this).
So if you use React as your front end library, you can easily benefit fast rendering of HTML and stopping unnecessary rendering of your DOM
I just want to do something simple like:
ReactDOM.find('img')
I can't seem to find anything in the documentation that does this. Do I just need to use jQuery? In my componentDidMount method, I want to add a listener to all img tags.
React does not have wrappers for convenient DOM access / DOM manipulation similar to jQuery because React recommends against having to access the DOM at all.
The DOM should be treated just as a rendering layer, not as a data store - your application state should entirely reside in javascript. Hence you never need to either access the DOM nor query it.
I've been reading about react.js library from Facebook lately, but I cannot see any difference between React and jQueryUI widget factory. Can someone make comparison between the two and tell me why should I use react.js instead of jQuery widget factory ?
Thanks
They aren't comparable, as they solve vastly different problems. jQueryUI widget factory is more a stateful wrapper around manipulating the dom with jquery. Not much different than writing objects where your render/update calls do jQuery DOM operations. ReactJS is more about 1 directional data flow & rendering. So when the state changes, it makes it all the dom changes behind the scenes on its virtual dom. Then diffs the updates to the real dom. Making it to be very fast, and very clean.
I've been learning React.js for a couple of months now, and my number 1 reason to use React.js is because of how it forces you to structure things. Keeping components self contained, and only manipulating the output by changing a state is vastly powerful. I've also come to like the Flux pattern, with the one direction of data flow.
Some of the non-react libraries I'm using perform some DOM generation with javascript. Ideally, I'd like this to occur in react's render cycle but react doesn't implement some DOM functions.
ie. one library wants to create a fragment for showing a title (using jQuery) which in turn ends up calling document.createDocumentFragment.
A simple work around is to have the library do it's rendering on component mount or update. But I'm trying to render using the virtual DOM. Is there a better approach to re-creating or porting the library?
You need a "Portal".
Take a look at https://github.com/ryanflorence/react-training/blob/gh-pages/lessons/05-wrapping-dom-libs.md
This explains the solution very well, like so:
Methodology:
DOM libs usually manipulate the DOM
React tries to re-render and finds a different DOM than it had last time and freaks out
We hide the DOM manipulation from React by breaking the rendering tree and then reconnecting around the DOM the lib manipulates.
Consumers of our component can stay in React-land.
React relies on the data-react-checksum attribute for reusing markup, which is only set in renderComponentToString (used for server-side rendering of components).
How can I reuse the react-component markup when the component is rendered client-side only?
Background
I'm working on a client-side only webapp. One of the project's goals is to render as quickly as possible, reducing UI "lag" from uninitialized elements, JS loading/parsing, and so forth.
I'm want to cache the rendered react-components markup using localStorage so the previous UI state can be restored as early as possible (again for performance reasons without waiting ~200ms for react to be loaded and parsed).
Strictly speaking, there's no way to turn a string of markup into a live React component (at least not in a performant way). Plus, it doesn't really make sense as your component might have had hidden state that aren't shown on the final rendered DOM string. If you try to revert the string into a component, it'll lead to state inconsistencies.
Something neat to do is to serialize your data into localStorage, and then reproduce your components from that data. But this more or less helps in your case.
But still, you can roll your own small logic on putting the string markup, then letting React destroy it subsequently by rendering a second time.