Ember.js MutableArray uniqBy() Method

Ember.js is an open-source JavaScript framework used for developing large client-side web applications which is based on Model-View-Controller (MVC) architecture. Ember.js is one of the most widely used front-end application frameworks. It is made to speed up development and increase productivity. Currently, it is utilized by a large number of websites, including Square, Discourse, Groupon, Linked In, Live Nation, Twitch, and Chipotle.

The uniqBy() method is used to get objects which unique value for the given key.

Syntax:

uniqBy(key)

Parameters:

• key: The key to get unique values.

Return Value: An array that has unique values for the given key.

To run the following examples you will need to have an ember project with you. To create one, you will need to install ember-cli first. Write the below code in the terminal:

npm install ember-cli

Now you can create the project by typing in the following piece of code:

ember new <project-name> --lang en

To start the server, type:

ember serve

Example 1: Type the following code to generate the route for this example:

ember generate route details

app/routes/details.js

import Route from '@ember/routing/route';

export default class DetailsRoute extends Route {
  details = [
    {
      name: 'Anubhav',
      mobile: '1298119967',
      city: 'Patna',
      country: 'India',
      gender: 'M',
      zipCode: '800020',
    },
    {
      name: 'Sakshi',
      mobile: '1234567890',
      city: 'Mumbai',
      country: 'India',
      gender: 'F',
      zipCode: '400001',
    },
    {
      name: 'Satyam',
      mobile: '2222222222',
      city: 'Delhi',
      country: 'India',
      gender: 'M',
      zipCode: '110012',
    },
    {
      name: 'Shivam',
      mobile: '1122113322',
      city: 'Bangalore',
      country: 'India',
      gender: 'M',
      zipCode: '530068',
    },
    {
      name: 'Ayushi',
      mobile: '2244668800',
      city: 'Jaipur',
      country: 'India',
      gender: 'F',
      zipCode: '302001',
    },
  ];
  someMoreDetails = [
    {
      name: 'Yeshwant',
      mobile: '1133557799',
      city: 'Chennai',
      country: 'India',
      gender: 'M',
      zipCode: '600001',
    },
    {
      name: 'Siddhant',
      mobile: '9911000000',
      city: 'Mangalore',
      country: 'India',
      gender: 'M',
      zipCode: '574142',
    },
    {
      name: 'Khushi',
      mobile: '8888888888',
      city: 'Pune',
      country: 'India',
      gender: 'F',
      zipCode: '111045',
    },
  ];
  start;
  end;
  idx;
  model() {
    return this.details;
  }
  setupController(controller, model) {
    super.setupController(controller, model);
    controller.set('details', this.details);
    controller.set('someMoreDetails',
        this.someMoreDetails);
    controller.set('start', this.start);
    controller.set('end', this.end);
    controller.set('idx', this.idx);
  }
}

app/controllers/details.js

import Ember from 'ember';
import { removeAt, unshiftObjects, objectAt, uniqBy, find }
         from '@ember/array';

export default Ember.Controller.extend({
    actions: {
        removeDetails(start, end) {
            this.details.removeAt(start, end);
        },
        addMoreDetails() {
            this.details.unshiftObjects(this.someMoreDetails);
        },
        getDetail(index) {
            let foo = this.details.objectAt(index);
            alert(foo.name);
        },
        getFirstMaleAndFemalePerson() {
            let foo = this.details.uniqBy('gender').toArray();
            let str = "";
            for (let i = 0; i < foo.length; i++)
                str += foo[i].name + "\n";
            alert(str);
        },
        getFirstMale() {
            let foo = this.details.find((detail) =>
            detail.gender === 'M');
            alert(foo.name);
        },
    },
});

app/template/details.hbs

{{page-title "Details"}}
<h3>List of People: </h3>
<br /><br />
<table>
    <tr>
        <th>Name</th>
        <th>Gender</th>
        <th>Mobile</th>
        <th>City</th>
        <th>Country</th>
        <th>Zip Code</th>
    </tr>
    {{#each @model as |detail|}}
    <tr>
        <td>{{detail.name}}</td>
        <td>{{detail.gender}}</td>
        <td>{{detail.mobile}}</td>
        <td>{{detail.city}}</td>
        <td>{{detail.country}}</td>
        <td>{{detail.zipCode}}</td>
    </tr>
    {{/each}}
</table>

<br /><br />
<div>
    <label>Enter Start Index: </label>
    {{input value=this.start}}
</div>
<div>
    <label>Enter End Index: </label>
    {{input value=this.end}}
</div>
<div>
    <input type="button" id="remove-details"
           value="Remove Details"
           {{action 'removeDetails' this.start this.end}} />
</div>
<br /><br />
<div>
    <label>Enter Index: </label>
    {{input value=this.idx}}
</div>
<div>
    <input type="button" id="get-detail"
           value="Get detail"
           {{action 'getDetail' this.idx}} />
</div>
<br /><br />
<input type="button" id="add-details"
       value="Add More Details"
       {{action 'addMoreDetails' }} />
<br /><br />
<input type="button" id="all-male"
       value="Get First Male"
       {{action 'getFirstMale' }} />
<br /><br />
<input type="button" id="get" value="Get"
       {{action 'getFirstMaleAndFemalePerson' }} />
{{outlet}}

Output: Visit localhost:4200/details to view the output

Example 2: Type the following code to generate the route for this example:

ember generate route websites

app/routes/websites.js

import Route from '@ember/routing/route';

export default class WebsitesRoute extends Route {
    websites = [
        {
            name: 'Wikipedia',
            link: 'www.wikipedia.com',
        },
        {
            name: 'Facebook',
            link: 'www.facebook.com',
        },
        {
            name: 'Google',
            link: 'www.google.com',
        },
        {
            name: 'Twitter',
            link: 'www.twitter.com',
        },
    ];
    moreWebsites = [
        {
            name: 'Google',
            link: 'www.google.com',
        },
        {
            name: 'Amazon',
            link: 'www.amazon.com',
        },
    ];
    model() {
        return this.websites;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set('websites', this.websites);
        controller.set('moreWebsites', this.moreWebsites);
    }
}

app/controllers/websites.js

import Ember from 'ember';
import { pushObjects, setEach } from '@ember/array';

export default Ember.Controller.extend({
    actions: {
        add() {
            this.websites.pushObjects(this.moreWebsites);
        },
        getUnique() {
            let foo = this.websites.uniqBy('name').toArray();
            let str = "";
            for (let i = 0; i < foo.length; i++)
                str += foo[i].name + "\n";
            alert(str);
        }
    },
});

app/template/websites.hbs

{{page-title "Websites"}}
<h3>Websites</h3>
<br /><br />
<table>
    <tr>
        <th>Name</th>
        <th>Website Link</th>
    </tr>
    {{#each @model as |website|}}
    <tr>
        <td>{{website.name}}</td>
        <td>{{website.link}}</td>
    </tr>
    {{/each}}
</table>
<br /><br />
<input type="button" id="add-website"
       value="More Websites" {{action 'add' }} />
<br /><br />
<input type="button" id="get-website"
       value="Click Here" {{action 'getUnique' }} />
{{outlet}}

Output: Visit localhost:4200/websites to view the output

Reference: https://api.emberjs.com/ember/4.4/classes/MutableArray/methods