Ember.js CoreObject init() Method

Last Updated : 26 Apr, 2025

Ember.js is an open-source JavaScript framework used for developing large client-side web applications which are 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 init() method is a method that is invoked whenever the object is instantiated.

Syntax:

init(){ //algorithm };

Step 1: 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

Step 2: 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 init1

app/components/arr2.js

JavaScript

import Component from '@glimmer/component';
import { tracked } from '@glimmer/tracking';
import { action } from '@ember/object';
import Ember from 'ember';

let Student = Ember.Object.extend({
    // these will be supplied by `create`
    firstName: null,
    lastName: null,

    init() {
        alert(`${this.get('firstName')} is Listed`);
    },
    fullName: Ember.computed('firstName', 'lastName', function () {
        return `${this.firstName} ${this.lastName}`;
    }),

    Changed: Ember.observer('fullName', function () {
        console.log(`fullName changed to: ${this.fullName}`);
    }),
});

export default Ember.Component.extend({
    students: [
        Student.create({
            firstName: 'Balit',
            lastName: 'stark',
            Id: 'stu2',
        }),
        Student.create({
            firstName: 'Permu',
            lastName: 'scott',
            Id: 'stu0',
        }),
        Student.create({
            firstName: 'Sam',
            lastName: 'melo',
            Id: 'stu1',
        }),
        Student.create({
            firstName: 'Pokhu',
            lastName: 'Verma',
            Id: 'stu3',
        }),
        Student.create({
            firstName: 'Tanu',
            lastName: 'Agrawal',
            Id: 'stu4',
        }),
        Student.create({
            firstName: 'Arabh',
            lastName: 'Singh',
            Id: 'stu5',
        })], 
 @tracked
item3: 'Gulshan',
 @tracked
item2: 'Verma',
 @tracked
item1: 'stu6',

 @action
print(data1, data2, data3) {
    let temp = Student.create({
        firstName: data1,
        lastName: data2,
        Id: data3
    });
    this.students.addObject(temp);
}
})

app/components/arr2.hbs

HTML

{{yield}}
<table>
    <tr>
        <th>Name</th>
        <th>Id</th>
      </tr>
      {{#each this.students as |detail|}}
    <tr>
        <td>{{detail.fullName}}</td>
          <td>{{get detail "Id"}}</td>
    </tr>
      {{/each}}
</table>
<br />
<div>
    <label>Enter Student FirstName: </label>
      {{input value=this.item3}}
</div>
<br />
<div>
    <label>Enter Student LastName: </label>
      {{input value=this.item2}}
</div>
<br />
<div>
    <label>Enter Student Id: </label>
      {{input value=this.item1}}
</div>
<br />
<input
    type="button"
      id="set-code"
      value="Update Student details"
      {{action "print" this.item3 this.item2 this.item1}}
/>

app/templates/init1.hbs

HTML

<Arr2><h3>Fruit's List :</h3></Arr2>

Output:

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

ember generate route init2

app/components/arr.js

JavaScript

import Component from '@glimmer/component';
import Ember from 'ember';
import EmberObject from '@ember/object';
import { action, without, set, get } from '@ember/object';

const Fruit = EmberObject.extend({
    init() {
        alert(`${this.get('name')} is in list Now`);
    }
});
export default Ember.Component.extend({

    fruits: [
        {
            'name': 'Lady Finger',
            'isFruit': false,
            'color': 'green'
        },
        {
            'name': 'Brinjal',
            'isFruit': false,
            'color': 'purple'
        },
        {
            'name': 'Apple',
            'isFruit': true,
            'color': 'red'
        },
        {
            'name': 'Grapes',
            'isFruit': true,
            'color': 'green'
        },
        {
            'name': 'Mango',
            'isFruit': true,
            'color': 'yellow'
        },
        {
            'name': 'Watermelon',
            'isFruit': true,
            'color': 'red'
        },
        {
            'name': 'Orange',
            'isFruit': true,
            'color': 'orange'
        }
    ],
 

 @action
insertItem(data, data1, data2) {
    let temp = Fruit.create({
        name: data,
        isFruit: data1,
        color: data2
    });
    this.fruits.addObject(temp);
}

})

app/components/arr2.hbs

HTML

{{page-title "Init"}}
<h3>{{yield}}</h3>
<table>
    <tr>
        <th>Name</th>
        <th>Fruit</th>
        <th>Color</th>
      </tr>
      {{#each this.fruits as |detail|}}
    <tr>
        <td>{{detail.name}}</td>
          <td>{{detail.isFruit}}</td>
          <td>{{detail.color}}</td>
    </tr>
      {{/each}}
</table>
<br /><br />
<div>
    <label>Enter Fruit Name: </label>
      {{input value=this.item1}}
</div><br />
<div>
    <label>Item is Fruit: </label>
      {{input value=this.item2}}
</div><br />
<div>
    <label>Enter Fruit color: </label>
      {{input value=this.item3}}
</div><br />
<div>
    <input
        type="button"
        id="insert-item"
        value="Insert Fruit"
        {{action "insertItem" this.item1 this.item2 this.item3}}
      />
</div>
{{outlet}}