Ember.js MutableArray insertAt() Method
Last Updated :
31 Aug, 2022
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 insertAt() method is used to insert an object in a specific position in the array.
Syntax:
insertAt(idx,obj)
Parameters:
- idx: The index where the insertion operation will take place.
- obj: The object to be inserted.
Return Value: The receiver.
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 list
app/routes/list.js
import Route from "@ember/routing/route";
export default class ListRoute extends Route {
list = ["a", "a", "v", "c", "c", "a",
"d", "q", "b", "z", "a"];
item;
idx;
model() {
return this.list;
}
setupController(controller, model) {
super.setupController(controller, model);
controller.set("list", this.list);
controller.set("item", this.item);
controller.set("idx", this.idx);
}
}
import Ember from "ember";
import {
clear, insertAt, indexOf, lastIndexOf,
includes
} from "@ember/array";
export default Ember.Controller.extend({
actions: {
insertItem(item, idx) {
this.list.insertAt(idx, item);
},
getLastIndex(item) {
let res = this.list.lastIndexOf(item);
alert(res);
},
getFirstIndex(item) {
let res = this.list.indexOf(item);
alert(res);
},
clearList() {
this.list.clear();
},
contains(item) {
let res = this.list.includes(item);
alert(`The list ${res ? "" : "does not"}
contains ${item}`);
},
},
});
{{page-title "List"}}
<h3>Here is a list of Items: </h3>
<ul>
{{#each @model as |i|}}
<li>{{i}}</li>
{{/each}}
</ul>
<br /><br />
<div>
<label>Enter Item: </label>
{{input value=this.item}}
</div>
<div>
<label>Enter Index: </label>
{{input value=this.idx}}
</div>
<div>
<input
type="button"
id="insert-item"
value="Insert Item"
{{action "insertItem" this.item this.idx}}
/>
</div>
<br /><br />
<div>
<label>Enter Item: </label>
{{input value=this.item}}
</div>
<div>
<input
type="button"
id="first-index-item"
value="Get First Index"
{{action "getFirstIndex" this.item}}
/>
</div>
<div>
<input
type="button"
id="last-index-item"
value="Get Last Index"
{{action "getLastIndex" this.item}}
/>
</div>
<div>
<input
type="button"
id="contains-item"
value="Contains?"
{{action "contains" this.item}}
/>
</div>
<br /><br />
<input type="button" id="clear-items" value="Clear"
{{action "clearList"}} />
{{outlet}}
Output: Visit localhost:4200/list to view the output
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Example 2: Type the following code to generate the route for this example:
ember generate route party
app/routes/party.js
import Route from "@ember/routing/route";
export default class PartyRoute extends Route {
partyItems = [
"Digital Camera",
"Jugs, cups & straws",
"Cold Drink",
"Balloons",
"Scissors",
"Wine",
"Cold Drink",
"Table Confetti",
"Party Hats",
"Wine",
"Napkins",
"Party Plates",
"Speakers",
"Wine",
"Music System",
"Cold Drink",
"Cups",
];
item;
idx;
model() {
return this.partyItems;
}
setupController(controller, model) {
super.setupController(controller, model);
controller.set("partyItems", this.partyItems);
controller.set("item", this.item);
controller.set("idx", this.idx);
}
}
import Ember from "ember";
import { insertAt, indexOf, lastIndexOf, includes }
from "@ember/array";
export default Ember.Controller.extend({
actions: {
insertItem(item, idx) {
this.partyItems.insertAt(idx, item);
},
getLastIndex(item) {
let res = this.partyItems.lastIndexOf(item);
alert(res);
},
getFirstIndex(item) {
let res = this.partyItems.indexOf(item);
alert(res);
},
clearpartyItems() {
this.partyItems.clear();
},
contains(item) {
let res = this.partyItems.includes(item);
alert(`The partyItems ${res ? "" : "does not"}
contains ${item}`);
},
},
});
{{page-title "Party"}}
<h3>Here is a list of items: </h3>
<ul>
{#each @model as |party|}}
<li>{{party}}</li>
{{/each}}
</ul>
<br /><br />
<div>
<label>Enter Item: </label>
{{input value=this.item}}
</div>
<div>
<label>Enter Index: </label>
{{input value=this.idx}}
</div>
<div>
<input
type="button"
id="insert-item"
value="Insert Item"
{{action "insertItem" this.item this.idx}}
/>
</div>
<br /><br />
<div>
<label>Enter Item: </label>
{{input value=this.item}}
</div>
<div>
<input
type="button"
id="first-index-item"
value="Get First Index"
{{action "getFirstIndex" this.item}}
/>
</div>
<div>
<input
type="button"
id="last-index-item"
value="Get Last Index"
{{action "getLastIndex" this.item}}
/>
</div>
<div>
<input
type="button"
id="contains-item"
value="Contains?"
{{action "contains" this.item}}
/>
</div>
<br /><br />
{{outlet}}
Output: Visit localhost:4200/party to view the output
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Reference: https://api.emberjs.com/ember/4.4/classes/MutableArray/methods