Madelyn  Frami

Madelyn Frami

1600676940

7 Ways to Implement Conditional Rendering in React Applications

Introduction

With React, we can build Single Page Applications that are dynamic and highly interactive. One way we fully utilize such interactivity is through conditional rendering.

Conditional rendering as a term describes the ability to render different UI markup based on certain conditions. In React-speak, it is a way to render different elements or components based on a condition. This concept is applied often in the following scenarios:

  • Rendering external data from an API
  • Showing/hiding elements
  • Toggling application functionality
  • Implementing permission levels
  • Authentication and Authorization

In this article, we examine seven(7) ways to implement such conditional rendering in React applications.

The Challenge

As a challenge, based on the value of isLoggedIn in our component state, we want to be able to display a Login button if the user isn’t logged in, and a Logout button if he/she is.

This is what our starter component looks like:

Visually:

Code:

import React, { Component } from "react";
import ReactDOM from "react-dom";
import "./styles.css";

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      isLoggedIn: true
    };
  }
  render() {
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        <button>Login</button>
        <button>Logout</button>
      </div>
    );
  }
}

const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

Copy

Bear in mind that  … within the code snippets implies that some code which isn’t directly connected with the point being explained goes there.

#react

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7 Ways to Implement Conditional Rendering in React Applications
Autumn  Blick

Autumn Blick

1598839687

How native is React Native? | React Native vs Native App Development

If you are undertaking a mobile app development for your start-up or enterprise, you are likely wondering whether to use React Native. As a popular development framework, React Native helps you to develop near-native mobile apps. However, you are probably also wondering how close you can get to a native app by using React Native. How native is React Native?

In the article, we discuss the similarities between native mobile development and development using React Native. We also touch upon where they differ and how to bridge the gaps. Read on.

A brief introduction to React Native

Let’s briefly set the context first. We will briefly touch upon what React Native is and how it differs from earlier hybrid frameworks.

React Native is a popular JavaScript framework that Facebook has created. You can use this open-source framework to code natively rendering Android and iOS mobile apps. You can use it to develop web apps too.

Facebook has developed React Native based on React, its JavaScript library. The first release of React Native came in March 2015. At the time of writing this article, the latest stable release of React Native is 0.62.0, and it was released in March 2020.

Although relatively new, React Native has acquired a high degree of popularity. The “Stack Overflow Developer Survey 2019” report identifies it as the 8th most loved framework. Facebook, Walmart, and Bloomberg are some of the top companies that use React Native.

The popularity of React Native comes from its advantages. Some of its advantages are as follows:

  • Performance: It delivers optimal performance.
  • Cross-platform development: You can develop both Android and iOS apps with it. The reuse of code expedites development and reduces costs.
  • UI design: React Native enables you to design simple and responsive UI for your mobile app.
  • 3rd party plugins: This framework supports 3rd party plugins.
  • Developer community: A vibrant community of developers support React Native.

Why React Native is fundamentally different from earlier hybrid frameworks

Are you wondering whether React Native is just another of those hybrid frameworks like Ionic or Cordova? It’s not! React Native is fundamentally different from these earlier hybrid frameworks.

React Native is very close to native. Consider the following aspects as described on the React Native website:

  • Access to many native platforms features: The primitives of React Native render to native platform UI. This means that your React Native app will use many native platform APIs as native apps would do.
  • Near-native user experience: React Native provides several native components, and these are platform agnostic.
  • The ease of accessing native APIs: React Native uses a declarative UI paradigm. This enables React Native to interact easily with native platform APIs since React Native wraps existing native code.

Due to these factors, React Native offers many more advantages compared to those earlier hybrid frameworks. We now review them.

#android app #frontend #ios app #mobile app development #benefits of react native #is react native good for mobile app development #native vs #pros and cons of react native #react mobile development #react native development #react native experience #react native framework #react native ios vs android #react native pros and cons #react native vs android #react native vs native #react native vs native performance #react vs native #why react native #why use react native

Mathew Rini

1615544450

How to Select and Hire the Best React JS and React Native Developers?

Since March 2020 reached 556 million monthly downloads have increased, It shows that React JS has been steadily growing. React.js also provides a desirable amount of pliancy and efficiency for developing innovative solutions with interactive user interfaces. It’s no surprise that an increasing number of businesses are adopting this technology. How do you select and recruit React.js developers who will propel your project forward? How much does a React developer make? We’ll bring you here all the details you need.

What is React.js?

Facebook built and maintains React.js, an open-source JavaScript library for designing development tools. React.js is used to create single-page applications (SPAs) that can be used in conjunction with React Native to develop native cross-platform apps.

React vs React Native

  • React Native is a platform that uses a collection of mobile-specific components provided by the React kit, while React.js is a JavaScript-based library.
  • React.js and React Native have similar syntax and workflows, but their implementation is quite different.
  • React Native is designed to create native mobile apps that are distinct from those created in Objective-C or Java. React, on the other hand, can be used to develop web apps, hybrid and mobile & desktop applications.
  • React Native, in essence, takes the same conceptual UI cornerstones as standard iOS and Android apps and assembles them using React.js syntax to create a rich mobile experience.

What is the Average React Developer Salary?

In the United States, the average React developer salary is $94,205 a year, or $30-$48 per hour, This is one of the highest among JavaScript developers. The starting salary for junior React.js developers is $60,510 per year, rising to $112,480 for senior roles.

* React.js Developer Salary by Country

  • United States- $120,000
  • Canada - $110,000
  • United Kingdom - $71,820
  • The Netherlands $49,095
  • Spain - $35,423.00
  • France - $44,284
  • Ukraine - $28,990
  • India - $9,843
  • Sweden - $55,173
  • Singapore - $43,801

In context of software developer wage rates, the United States continues to lead. In high-tech cities like San Francisco and New York, average React developer salaries will hit $98K and $114per year, overall.

However, the need for React.js and React Native developer is outpacing local labour markets. As a result, many businesses have difficulty locating and recruiting them locally.

It’s no surprise that for US and European companies looking for professional and budget engineers, offshore regions like India are becoming especially interesting. This area has a large number of app development companies, a good rate with quality, and a good pool of React.js front-end developers.

As per Linkedin, the country’s IT industry employs over a million React specialists. Furthermore, for the same or less money than hiring a React.js programmer locally, you may recruit someone with much expertise and a broader technical stack.

How to Hire React.js Developers?

  • Conduct thorough candidate research, including portfolios and areas of expertise.
  • Before you sit down with your interviewing panel, do some homework.
  • Examine the final outcome and hire the ideal candidate.

Why is React.js Popular?

React is a very strong framework. React.js makes use of a powerful synchronization method known as Virtual DOM, which compares the current page architecture to the expected page architecture and updates the appropriate components as long as the user input.

React is scalable. it utilises a single language, For server-client side, and mobile platform.

React is steady.React.js is completely adaptable, which means it seldom, if ever, updates the user interface. This enables legacy projects to be updated to the most new edition of React.js without having to change the codebase or make a few small changes.

React is adaptable. It can be conveniently paired with various state administrators (e.g., Redux, Flux, Alt or Reflux) and can be used to implement a number of architectural patterns.

Is there a market for React.js programmers?
The need for React.js developers is rising at an unparalleled rate. React.js is currently used by over one million websites around the world. React is used by Fortune 400+ businesses and popular companies such as Facebook, Twitter, Glassdoor and Cloudflare.

Final thoughts:

As you’ve seen, locating and Hire React js Developer and Hire React Native developer is a difficult challenge. You will have less challenges selecting the correct fit for your projects if you identify growing offshore locations (e.g. India) and take into consideration the details above.

If you want to make this process easier, You can visit our website for more, or else to write a email, we’ll help you to finding top rated React.js and React Native developers easier and with strives to create this operation

#hire-react-js-developer #hire-react-native-developer #react #react-native #react-js #hire-react-js-programmer

Dipen Shah

Dipen Shah

1571987532

7 Ways to Implement Conditional Rendering in React Applications

With React, we can build Single Page Applications that are dynamic and highly interactive. One way we fully utilize such interactivity is through conditional rendering.

Conditional rendering as a term describes the ability to render different UI markup based on certain conditions. In React-speak, it is a way to render different elements or components based on a condition. This concept is applied often in the following scenarios:

  • Rendering external data from an API
  • Showing/hiding elements
  • Toggling application functionality
  • Implementing permission levels
  • Authentication and Authorization

In this article, we examine seven(7) ways to implement such conditional rendering in React applications.

Table of Contents

The Challenge

As a challenge, based on the value of isLoggedIn in our component state, we want to be able to display a Login button if the user isn’t logged in, and a Logout button if he/she is.

This is what our starter component looks like:

Visually:

7 Ways to Implement Conditional Rendering in React Applications

Code:

import React, { Component } from "react";
import ReactDOM from "react-dom";
import "./styles.css";

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      isLoggedIn: true
    };
  }
  render() {
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        <button>Login</button>
        <button>Logout</button>
      </div>
    );
  }
}

const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

Starter Code Fork this CodeSandBox to get started.

START HERE 👉🏾 https://codesandbox.io/s/conditional-rendering-demo-ei72f

Let’s Begin!

The Solution

Please bear in mind that … within the code snippets implies that some code which isn’t directly connected with the point being explained goes there.

1. Using an If…else Statement

An if…else statement allows us to speficy that a particular action be carried out if a condition evaluates to true as well as do something else if it doesn’t. Using the sample project, we will examine two ways if…else conditions may be used to implement conditional rendering in React.

  • Extracting the conditional rendering into a function

In JSX, we are able to mix up JavaScript code with our markup to ensure stunning interactivity within our application. To do this we use a set of curly braces {} and write our JavaScript within. The caveat however is that there is a limit to what can be done within such braces. As a result the code snippet below would fail to achieve the desired result.

// index.js
...
render() {
    let {isLoggedIn} = this.state;
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {
          if(isLoggedIn){
            return <button>Logout</button>
          } else{
            return <button>Login</button>
          }
        }
      </div>
    );
}
...

To understand more about this behaviour, visit this link.

To solve this, we extract the conditional logic into a function as shown below:

// index.js
...
render() {
    let {isLoggedIn} = this.state;
    const renderAuthButton = ()=>{
      if(isLoggedIn){
        return <button>Logout</button>
      } else{
        return <button>Login</button>
      }
    }
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {renderAuthButton()}
      </div>
    );
  }
...

Notice that we extract the logic from JSX into a function renderAuthButton. Thus, we only need to execute the function within the JSX curly braces.

  • Multiple return statements.

In using this method, the component must be kept as simple as possible to avoid a wasted re-render of sibling or parent components. As a result of this, we create a new functional component called AuthButton.

// AuthButton.js

import React from "react";

const AuthButton = props => {
  let { isLoggedIn } = props;
  if (isLoggedIn) {
    return <button>Logout</button>;
  } else {
    return <button>Login</button>;
  }
};
export default AuthButton;

AuthButton returns various elements/components depending on the value of state that is passed down via the isLoggedIn props. Thus we import it in our index.js and pass down the appropriate state as shown below:

// index.js
...
import AuthButton from "./AuthButton";

...
  render() {
    let { isLoggedIn } = this.state;
    return (
      <div className="App">
      ...
        <AuthButton isLoggedIn={isLoggedIn} />
      </div>
    );
  }
...

You must avoid doing this:

// index.js
...
render() {
    let { isLoggedIn } = this.state;
    if (isLoggedIn) {
      return (
        <div className="App">
          <h1>
            This is a Demo showing several ways to implement Conditional
            Rendering in React.
          </h1>
          <button>Logout</button>;
        </div>
      );
    } else {
      return (
        <div className="App">
          <h1>
            This is a Demo showing several ways to implement Conditional
            Rendering in React.
          </h1>
          <button>Login</button>
        </div>
      );
    }
  }
}
...

The snippet above would achieve the same result but bloat the component unnecessarily while introducing performance issues as a result of constantly rerendering an unchanging component.

2. Using Element Variables

Element variables are an extension of **Extracting the conditional rendering into a function** as shown above. Element variables are simply variables that hold JSX elements. Thus we can conditionally assign elements/ components to these variables outside our JSX and only render the variable within JSX. See demo below:

// index.js
...
render() {
    let { isLoggedIn } = this.state;
    let AuthButton;
    if (isLoggedIn) {
      AuthButton = <button>Logout</button>;
    } else {
      AuthButton = <button>Login</button>;
    }
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {AuthButton}
      </div>
    );
  }
...

Notice how we conditionally assign values(components) to AuthButton and then we only have to render it neatly within our JSX.

3. Using a Switch Statement

As shown previously, we can conditionally return different markup from a component based on set conditions using an if…else statement. The same could be achieved with a switch statement where we can specify the markup for various conditions. See example below:

// AuthButton.js
import React from "react";

const AuthButton = props => {
  let { isLoggedIn } = props;
  switch (isLoggedIn) {
    case true:
      return <button>Logout</button>;
      break;
    case false:
      return <button>Login</button>;
      break;
    default:
      return null;
  }
};
export default AuthButton;

Notice how we return various buttons based on the value of isLoggedIn. It is more reasonable to apply this method when there’s more than two possible values or outcomes. You may also do away with the break statement as the return statement automatically terminates the execution.

Note: Returning **null** from a component will cause it to hide itself/display nothing. This a good way to toggle visibility of components.

4. Ternary Operators

The conditional (ternary) operator is the only JavaScript operator that takes three operands. This operator is frequently used as a shortcut for the if statement.

If you are familiar with ternary operators, then you are aware that is is simply a more concise way to write an if statement. Thus we have:

// index.js
...
render() {
    let { isLoggedIn } = this.state;
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {isLoggedIn ? <button>Logout</button> : <button>Login</button>}
      </div>
    );
  }
...

In cases where, this approach makes the component bloated, bulky or less readable, you may encapsualte the conditional within a functional component as shown below:

// AuthButton.js
import React from "react";

const AuthButton = props => {
  let { isLoggedIn } = props;
  return isLoggedIn ? <button>Logout</button> : <button>Login</button>;
};

export default AuthButton;

5. Logical && (Short Circuit Evaluation with &&)

Short circuit evaluation is a technique used to ensure that there are no side effects during the evaluation of eperands in an expression. The logical && helps us specify that an action should be taken only on one condition, otherwise, it would be ignored entirely. This is useful for situations where you only need to take an action when a certain condition is true, otherwise do nothing.

For instance if we only needed to show the Logout button if the person is logged in, otherwise we do nothing. We’d have something like this:

// index.js
...
render() {
    let { isLoggedIn } = this.state;
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {isLoggedIn && <button>Logout</button>}
      </div>
    );
  }
...

This would display the logout button if isLoggedIn is true otherwise it’d display nothing. We could adapt this to fit our use case as shown below. However, it is not advisable.

// index.js
...
return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {isLoggedIn && <button>Logout</button>}
        {!isLoggedIn && <button>Login</button>}
      </div>
    );
  }
...

This would render the right button based on the value of isLoggedIn. However, this isn’t recommended as there are better, cleaner ways to achieve the same effect. Also this could easily make your code look messy and uninuitive once the component gets slightly larger.

6. Using Immediately Invoked Function Expressions(IIFEs)

Okay! Rememeber how we said JSX had limitations and wouldn’t be able to execute every JavaScript code? Well, this is isn’t entirely true as there are ways to bypass such behaviour. One such way is by using IIFEs.

An IIFE (Immediately Invoked Function Expression) is a JavaScript function that runs as soon as it is defined. It’s used in the format below.

(function () {
    statements
})();

You may learn more here.

With this technique, we are able to to write conditional logic directly within JSX but wrapped within an anonymous function that is immediately invoked on evaluation of that portion of our code. See example below:

//index.js
...
render() {
    let { isLoggedIn } = this.state;
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {(function() {
          if (isLoggedIn) {
            return <button>Logout</button>;
          } else {
            return <button>Login</button>;
          }
        })()}
      </div>
    );
  }
...

This can also be written in a slightly more concise manner using an arrow function as shown below:

// index.js
...
return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        {(()=> {
          if (isLoggedIn) {
            return <button>Logout</button>;
          } else {
            return <button>Login</button>;
          }
        })()}
      </div>
    );
  }
...

7. Using Enhanced JSX

Certain libaries expose functionality to extend JSX, thus making it possible to implement conditional rendering directly with JSX. One of such libraries is JSX Control Statements. It is a Babel plugin that transforms component-like control statements into their JavaScript counterparts during transpilation. See example below for how this may be implemented.

// index.js
...
return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        <Choose>
          <When condition={isLoggedIn}>
             <button>Logout</button>;
          </When>
          <When condition={!isLoggedIn}>
             <button>Login</button>;
          </When>
        </Choose>
      </div>
    );
  }
...

This approach is however not recommended as the code you write is eventually transpiled to a regular JavaScript conditional. It is probably always better to just write JavaScript than add an extra dependency over something so trivial.

Performance Concerns

As a general rule, it is best to ensure that in implemementing conditional rendering you:

  • Do not change the position of components arbitrarily in order to prevent components from unmounting and remounting unnecessarily.
  • Change only the markup that is concerned with the conditional rendering and leave out every other unchanging bit of the component.
  • Do not bloat your component unnecessarily within the render method, thus causing components to delay in rendering.

For more on writing high performing conditionals in React, see this article by Cole Williams.

Conclusion

We have successfully examined 7 ways to implement conditional rendering in React. Each method has it’s own advantage and the choice of which to use is mostly dependent on the use case. Things to consider include:

  • The size of markup to be rendered conditionally

  • The number of possible outcomes

  • Which would be more intuitive and readable

    Generally,I would recommend that:

  • When there is only one expected outcome, the Logical && Operator comes in very handy.

  • For boolean situations or use cases with only 2 possible outcomes, you may use If…else, Element variables, Ternary Operators and IIFEs.

  • For cases of more than 2 outcomes, you may use a Switch statement, an extracted function or extracted functional component.

This is however merely a recommendation and the choice of which to go with is primarily yours.

#react #javascript #web-development

Madelyn  Frami

Madelyn Frami

1600676940

7 Ways to Implement Conditional Rendering in React Applications

Introduction

With React, we can build Single Page Applications that are dynamic and highly interactive. One way we fully utilize such interactivity is through conditional rendering.

Conditional rendering as a term describes the ability to render different UI markup based on certain conditions. In React-speak, it is a way to render different elements or components based on a condition. This concept is applied often in the following scenarios:

  • Rendering external data from an API
  • Showing/hiding elements
  • Toggling application functionality
  • Implementing permission levels
  • Authentication and Authorization

In this article, we examine seven(7) ways to implement such conditional rendering in React applications.

The Challenge

As a challenge, based on the value of isLoggedIn in our component state, we want to be able to display a Login button if the user isn’t logged in, and a Logout button if he/she is.

This is what our starter component looks like:

Visually:

Code:

import React, { Component } from "react";
import ReactDOM from "react-dom";
import "./styles.css";

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      isLoggedIn: true
    };
  }
  render() {
    return (
      <div className="App">
        <h1>
          This is a Demo showing several ways to implement Conditional Rendering
          in React.
        </h1>
        <button>Login</button>
        <button>Logout</button>
      </div>
    );
  }
}

const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);

Copy

Bear in mind that  … within the code snippets implies that some code which isn’t directly connected with the point being explained goes there.

#react

What are hooks in React JS? - INFO AT ONE

In this article, you will learn what are hooks in React JS? and when to use react hooks? React JS is developed by Facebook in the year 2013. There are many students and the new developers who have confusion between react and hooks in react. Well, it is not different, react is a programming language and hooks is a function which is used in react programming language.
Read More:- https://infoatone.com/what-are-hooks-in-react-js/

#react #hooks in react #react hooks example #react js projects for beginners #what are hooks in react js? #when to use react hooks