Vegard  Sandnes

Vegard Sandnes

1564039968

How to Creat a Dynamic <select> Menu with React

React is still new to me, along with everything that is software development. Therefore, it takes a bit more mental computation to understand exactly what I’m trying to accomplish.

In this case, I needed to understand how to get previously-stored values into a element in a form. The idea is that the user is utilizing this form to record meditation sessions — or what I refer to as mindful moments — and in this form the user records the location where they had that mindful moment. Chances are they’re going to meditate in the same location more than once, so we need to make it so that the user can either use an already-existing location, or create a new one.

Code Walk-through

Let’s see how to do this…

// LocationSelect component
import React from 'react';
import { connect } from 'react-redux';
import { getMoments } from '../actions/moments';

Of course, we need to import React and connect, and also the action to get our list of moments — a call to our API — which contains the location that we need for our later on.

Let’s initialize our component’s state:

class LocationSelect extends React.Component {
  constructor(props){
    super(props);
    this.state = {
      location: ''
    };
  }

So we’re telling our component to store a location key in its state, but not yet giving it a value. We just giving that value a place to go later on.

Let’s get our moments object from our API:

  componentDidMount(){
    if (this.props.authToken){
     getMoments(this.props.authToken);
    }
  }

If our props contains the authToken , then run the getMoments action with that authToken. We want this to happen once this component mounts.

Inside our render(), we want to sort our select menu’s options to make it more user-friendly. To do this, we need to first get all of our previously-entered data, store it in a new array, then sort that array.

render() {
  let momentsList = [];
**  this**.props.moments.forEach(({ *id*, *location* }) => momentsList.push({ id, location }));
  let uniqueSet = [...new Set(momentsList.map(*moment* => moment.location))];

So we create our new array, momentsList. Since they’re passed as props, we need to grab them from there, and run a forEach, grabbing the id and the location from *each *iteration (in this case, each moment). Then, we’re pushing id and location into our new array from each moment we iterate over. We only want the id and location, not any other information that might be stored in that object.

We then need to create a new Set, so that we can store data of any type. We’re saying, Create a new array called uniqueSet, which will be a new Set created from a map() over our previous array, grabbing the location.

*I know this is rather messy — I’d love to know of a more succinct way to do this if possible!

Next, let’s sort that new array alphabetically:

let sortedList = uniqueSet
  .sort((*a*, *b*) => {
    *if* (a < b) *return* *-1*;
    *else* *if* (a > b) *return* *1*;
    *return* *0*;
  })
  .map((*location*, *index*) => <option key={index}>{location}</option>);

Here, we’re just sorting alphabetically. this is a rather common process. Basically, if parameter a is less than parameter b, return -1, but if a is greater than b, return 1, otherwise return 0.

As I understand it, this is looking at each bit and determining whether it is greater or less than the bit next to it, and sorting it according to our specifications. The least value letter is a, while the greatest value is z.

Our map function is taking the location and index of each of those now-sorted items and putting them into an for our to use later. Notice we’re using the index as our key for React, and location as our text to display.

Inside our return statement is where we’re going to see all of this come to fruition on the user-side.

return (
      <div className="dropdown">
        <label htmlFor="location">Location</label>
        <input
          required
          className="form-input"
          type="text"
          name="location"
          placeholder="create or choose"
          value={this.props.location}
          onChange={event => this.handleTextFieldChange(event, 'location')}
          maxLength="20"
          autoComplete="off"
        />
        <select onChange={event => this.handleTextFieldChange(event, 'location')}>
          {sortedList}
        </select>
      </div>
    );

Here you can see that we are rendering to the page an and our . Our input is the text field used to create a new location, while our select is where we’re rendering all previously-enter location items.

Our select is receiving our sortedList array to be used as s — remember when we wrote that above?

If we scroll up in our imaginative document here, we need to write our onChange handler, handleTextFieldChange.

handleTextFieldChange(event) {
    let location = event.target.value;
    let text = location // capitalize first letter
      .toLowerCase()
      .split(' ')
      .map(s => s.charAt(0).toUpperCase() + s.substr(1))
      .join(' ');
    this.props.setLocation(text, 'location');
  }

event.target.value is either our input or our select. If we type into our input field, or if we select an option from the menu. We’re also manipulating all text that gets put into that input field; we’re capitalizing the first character. This helps to keep things looking tidy. Users might feel like capitalizing one day, or using all lowercase the next. This way, our stored data is uniform.

Then we finish off our component:

const mapStateToProps = state => ({
  moments: state.moments.moments,
  authToken: state.auth.authToken
});
export default connect(mapStateToProps)(LocationSelect);

and render it in our parent component after importing it.

I understand this is a rough how-to. As one with not a ton of experience with React and JavaScript, and having no one in-person to bounce ideas off of, I was left with reading docs and seeing what others have done. I never did find something doing this same thing, so I had to utilize what I could piece together. For instance, Set is very new to me, and I honestly don’t think I used it in the correct manner. That said, it’s what worked for what I needed.

I do hope this has helped someone, and I very much welcome any and all input. Below, you can find the component in its entirety:

import React from 'react';
import { connect } from 'react-redux';
import { getMoments } from '../actions/moments';

class LocationSelect extends React.Component {
constructor(props) {
super(props);
this.state = {
location: ‘’
};
}

componentDidMount() {
if (this.props.authToken) {
getMoments(this.props.authToken);
}
}

handleTextFieldChange(event) {
let location = event.target.value;
let text = location // capitalize first letter
.toLowerCase()
.split(’ ‘)
.map(s => s.charAt(0).toUpperCase() + s.substr(1))
.join(’ ');
this.props.setLocation(text, ‘location’);
}

render() {
let momentsList = [];
this.props.moments.forEach(({ id, location }) => momentsList.push({ id, location }));
let uniqueSet = […new Set(momentsList.map(moment => moment.location))];

// sort list alpha, map to render
let sortedList = uniqueSet
.sort((a, b) => {
if (a < b) return -1;
else if (a > b) return 1;
return 0;
})
.map((location, index) => <option key={index}>{location}</option>);

// store locations to state
return (
<div className=“dropdown”>
<label htmlFor=“location”>Location</label>
<input
required
className=“form-input”
type=“text”
name=“location”
placeholder=“create or choose”
value={this.props.location}
onChange={event => this.handleTextFieldChange(event, ‘location’)}
maxLength=“20”
autoComplete=“off”
/>
<select onChange={event => this.handleTextFieldChange(event, ‘location’)}>
{sortedList}
</select>
</div>
);
}
}

const mapStateToProps = state => ({
moments: state.moments.moments,
authToken: state.auth.authToken
});


export default connect(mapStateToProps)(LocationSelect);


Thanks for reading. If you liked this post, share it with all of your programming buddies!

Further reading

How to Build First React Website

Learn about Video Navigation in React

☞ React - The Complete Guide (incl Hooks, React Router, Redux)

☞ Modern React with Redux [2019 Update]

☞ Best 50 React Interview Questions for Frontend Developers in 2019

☞ Learn React - Full Course for Beginners - React Tutorial 2019

☞ React (without Redux) - JWT Authentication Tutorial & Example

☞ React vs Angular vs Vue.js by Example

☞ MERN Stack Tutorial - Build a MERN App From Scratch ❤


This post was originally published here

#reactjs #react-native #javascript #web-development

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How to Creat a Dynamic <select> Menu with React
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

Einar  Hintz

Einar Hintz

1593229920

Android Menu - Steps to implement Menu in Android - DataFlair

Types of Android Menu

Let us see the various types of menu in Android:

1. Android Options Menu

The Options Menu is a collection of options for an activity. It has a set of items that are useful to perform actions. It helps us to combine multiple actions together.

Following is an example of Options Menu:

Options Menu in Android

2. PopUp Menu

Pop-Up menu is a menu that displays a list of items in a popup window. A pop-up menu appears below the view by default, in case there is no space, it appears above it.

Android Pop Up menu

3. Contextual Menu

A contextual menu is a floating menu. It appears only when the users long-press an element or right clicks on that. It generally affects the selected element.

Contextual menu

#android tutorials #android menu #android menu types #contextual menu #menu android #menu in android #options menu #types of menu in android

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

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

Aria Barnes

Aria Barnes

1627031571

React 18: Things You Need To Know About React JS Latest Version

The most awaited version of React 18 is finally out now. Its team has finally revealed the alpha version of React 18 and its plan, though the official launch is still pending. This time the team has tried something and released the plan first to know their user feedback because the last version of React 17 was not that much appreciated among developers.

According to Front-end Frameworks SurveyReact JS has ranked top in the list of most loved frameworks. Thus, the developer communities expect a bit higher from the framework, so they are less appreciative of the previous launch.
ReactJS stats.pngSo, this time React 18 will be a blast. For beginners, the team is working on a new approach. They have called a panel of experts, library authors, educators, and developers to take part in a working group. Initially, it will be a small group.

I am not a part of this release but following the team on their GitHub discussion group. After gathering the information from there, I can say that they have planned much better this time.

React 17 was not able to meet the developer's community. The focus was all primarily centered on making it easier to upgrade React itself. React 18 release will be the opposite. It has a lot of features for react developers.

Read more here: React 18: Things You Need To Know About React JS Latest Version

#hire react js developers #hire react js developers india #react developers india #react js developer #react developer #hire react developers