Ember.js ArrayProxy map() 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 map() method is used to map all the items in the enumeration to another value and return a new array.

Syntax:

map( callback, target );

Parameters:

• callback: It is the callback to execute on each item.
• target: It is the item on which callback will invoke.

Return Value: Return new mapped array.

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 map1

app/routes/map1.js

import Route from '@ember/routing/route';
import { classify, w } from '@ember/string';
import { map } from '@ember/array';

export default class LanguagesRoute extends Route {
    name = `Hindi Korean Marathi Telugu Portuguese
        Turkish Bengali Spanish`;
    num = `343.9 81.7 83.1 82.0 232.4 82.3 233.7 474`;

    languages = [];

    initLanguages() {
        this.languages = [];
        this.name = w(this.name);
        this.num = w(this.num);
        for (let i = 0; i < this.name.length; i++) {
            let obj = new Object();
            obj['name'] = classify(this.name[i]);
            obj['num'] = this.num[i];
            this.languages.pushObject(obj);
        }
    }
    temp1;
    convert(string) {
        this.item = string.split(",").map((item)
            => item.trim());
        return this.item;
    }

    model() {
        this.initLanguages();
        return this.languages;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set('languages', this.languages);
        controller.set('temp1', this.temp1);
        controller.set('convert', this.convert)
    }
}

app/controllers/map1.js

import Ember from 'ember';
import { map } from '@ember/array';

export default Ember.Controller.extend({
    actions: {
        get_Name() {
            let ans = this.languages.mapBy('name');
            alert(ans.join('\n'));
        },
        get_most() {
            let temp = 0;
            let tempItems = this.languages.map((item) =>
                temp < JSON.parse(item.num) ? temp =
                item.name : temp);
            alert(temp);

        },
        remove() {
            this.languages.popObject();
        },
        check_item(idx) {
            let temp = this.languages.objectAt(JSON.parse(idx));
            alert(temp.name)
        },
        check_items(idx) {
            idx = this.convert(idx);
            let temp = this.languages.objectsAt(idx);
            let ans = temp.mapBy('name')
            alert(ans.join('\n'))
        },

    },
});

app/templates/map1.hbs

{{page-title "map"}}
<h2>Spoken Languages in the World</h2>
<table style="border: 2px solid black;padding: 30px;">
    <tr>
        <th>Language</th>
        <th>Native Speakers (in Millions)</th>
      </tr>
      {{#each @model as |language|}}
    <tr>
        <td>{{language.name}}</td>
          <td>{{language.num}}</td>
    </tr>
      {{/each}}
</table>
<br /><br />
<div>
    <label>Enter index: </label>
      {{input value=this.temp}}
</div>
<input
    type="button"
      id="increase-pocket-money"
      value="Get Language at Index"
      {{action "check_item" this.temp}}
/>
<br /><br />
<div>
    <label>Enter indexs: </label>
      {{input value=this.temp2}}
</div>
<input
    type="button"
      id="check-atIndex"
      value="Check at indexes"
      {{action "check_items" this.temp2}}
/>
<br />
<br />
<div>
    <input
        type="button"
        id="check-fruit"
        value="Check Most speaking Language"
        {{action "get_most"}}
      />
</div>
<br />
<div>
    <input
        type="button"
        id="remove-item"
        value="Remove Last Element"
        {{action "remove"}}
      />
</div>
<br />
<div>
    <input
        type="button"
        id="show-lang"
        value="Show Language"
        {{action "get_Name"}}
      />
</div>
{{outlet}}

Output: Visit localhost:4200/map1 to view the output

Ember.js ArrayProxy map method

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

ember generate route map2

app/routes/map2.js

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

export default class StudentsRoute extends Route {
    students = [
        {
            name: "Aaush Somankar",
            gender: "M",
            class: 12,
            grade: "A",
        },
        {
            name: "Aman Prakash",
            gender: "M",
            class: 10,
            grade: "A",
        },
        {
            name: "Siya guru",
            gender: "F",
            class: 11,
            grade: "B",
        },
        {
            name: "Ramesh verma",
            gender: "M",
            class: 10,
            grade: "A",
        },
        {
            name: "Esnoor",
            gender: "M",
            class: 9,
            grade: "F",
        },
        {
            name: "Balit",
            gender: "M",
            class: 10,
            grade: "A",
        },
        {
            name: "Dora",
            gender: "F",
            class: 12,
            grade: "F",
        },
        {
            name: "Lalu",
            gender: "F",
            class: 8,
            grade: "A",
        },
        {
            name: "Pokhraj",
            gender: "M",
            class: 11,
            grade: "F",
        },
        {
            name: "Citu",
            gender: "M",
            class: 8,
            grade: "C",
        },
        {
            name: "Rahul",
            gender: "M",
            class: 9,
            grade: "A",

        },
        {
            name: "Ram",
            gender: "M",
            class: 12,
            grade: "A",
        },
        {
            name: "Priti",
            gender: "F",
            class: 9,
            grade: "F",
        },
        {
            name: "Flip",
            gender: "M",
            class: 9,
            grade: "B",
        },
        {
            name: "Sita",
            gender: "F",
            class: 8,
            grade: "A",
        },
        {
            name: "Aashray",
            gender: "M",
            class: 12,
            grade: "C",
        },
        {
            name: "Suneel",
            gender: "M",
            class: 8,
            grade: "C",
        },
    ];
    convert(string) {
        this.item = string.split(",").
            map((item) => item.trim());
        return this.item;
    }

    model() {
        return this.students;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set("students", this.students);
        controller.set("convert", this.convert);
        controller.set("item", this.item);
    }
}

app/controllers/map2.js

import Ember from "ember";

export default Ember.Controller.extend({
    actions: {
        getAllNames() {
            let res = this.students.mapBy('name');
            alert(res.join('\n'));
        },
        allPass() {
            let temp = '';
            let tempItems = this.students.map((item) =>
                item.grade == 'F' ? temp +=
                item.name + '\n' : temp);
            alert(temp);

        },
        remove() {
            this.students.popObject();
        },
        check_item(idx) {
            let temp = this.students.objectAt(JSON.parse(idx));
            alert(temp.name)
        },
        check_items(idx) {
            idx = this.convert(idx);
            let temp = this.students.objectsAt(idx);
            let ans = temp.mapBy('name')
            alert(ans.join('\n'))
        },

    },
});

app/templates/map2.hbs

{{page-title "map"}}
<h3>List of Students: </h3>

<table>
    <tr>
        <th>Name</th>
        <th>Class</th>
        <th>Gender</th>
        <th>Grade</th>
      </tr>
      {{#each @model as |student|}}
    <tr>
        <td>{{student.name}}</td>
          <td>{{student.class}}</td>
          <td>{{student.gender}}</td>
          <td>{{student.grade}}</td>
    </tr>
  {{/each}}
</table>
<br /><br />
<input
    type="button"
      id="get-all"
      value="Get All Names"
      {{action "getAllNames"}}
/>
<br /><br />
<input
    type="button"
      id="all-pass"
      value="Failed Student"
      {{action "allPass"}}
/>

<br /><br />
<div>
    <label>Enter index: </label>
      {{input value=this.temp}}
</div>
<input
    type="button"
      id="increase-pocket-money"
      value="Get Person at Index"
      {{action "check_item" this.temp}}
/>
<br /><br />
<div>
    <label>Enter indexs: </label>
      {{input value=this.temp2}}
</div>
<input
    type="button"
      id="check-atIndex"
      value="Check at indexes"
      {{action "check_items" this.temp2}}
/>
<br /><br />
<input
    type="button"
      id="remove-last"
      value="Remove Last Student"
      {{action "remove"}}
/>
{{outlet}}

Output: Visit localhost:4200/map2 to view the output

Ember.js ArrayProxy map method

Reference: https://api.emberjs.com/ember/4.6/classes/ArrayProxy/methods/map?anchor=map