Ember.js MutableArray reverseObjects() Method

Last Updated : 24 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 reverseObjects() method reverses the elements in the array.

Syntax:

reverseObjects()

Parameters: It takes no parameters.

Return Value: Reversed array.

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: "Patna", 
            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", 
        }, 
    ]; 
    city; 
    start; 
    end; 
    model() { 
        return this.details; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set("details", this.details); 
        controller.set("someMoreDetails", this.someMoreDetails); 
        controller.set("city", this.city); 
        controller.set("start", this.start); 
        controller.set("end", this.end); 
    } 
} 

app/controllers/details.js

import Ember from "ember"; 
import { any, slice, reverseObjects, rejectBy } from "@ember/array"; 
  
export default Ember.Controller.extend({ 
    actions: { 
        checkCity(city) { 
            let res = this.details.any( 
                (person) => person.city == city); 
            alert(`Present: ${res ? "YES" : "NO"}`); 
        }, 
        sliceItems(start, end) { 
            let tempItems = this.details.slice(start, end); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++) 
                str += tempItems[i].name + "\n"; 
            alert(str); 
        }, 
        reverse() { 
            this.set("details", this.details.reverseObjects()); 
        }, 
        getFemale() { 
            let tempItems = this.details.rejectBy("gender", "M"); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++) 
                str += tempItems[i].name + "\n"; 
            alert(str); 
        }, 
        pushMoreDetails() { 
            this.details.pushObjects(this.someMoreDetails); 
        }, 
    }, 
}); 

app/template/details.js

{ { 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 City: </label> 
    {{input value=this.city}} 
</div> 
<div> 
    <input type="button" id="check-city" 
           value="Check" 
           {{action 'checkCity' this.city}} /> 
</div> 
<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="slice-items" 
           value="Slice Items"
           {{action 'sliceItems' this.start this.end}} /> 
</div> 
<br /><br /> 
<input type="button" id="push-details" 
       value="Add More Details"
       {{action 'pushMoreDetails' }} /> 
<br /><br /> 
<input type="button" id="reverse" 
       value="Reverse" 
       {{action 'reverse' }} /> 
<br /><br /> 
<input type="button" id="get-female" 
       value="Get Female"
       {{action 'getFemale' }} />

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 party

app/routes/party.js

import Route from "@ember/routing/route"; 
  
export default class PartyRoute extends Route { 
    partyItems = [ 
        "Digital Camera", 
        "Jugs, cups & straws", 
        "Balloons", 
        "Scissors", 
        "Cold Drink", 
        "Table Confetti", 
        "Party Hats", 
        "Wine", 
        "Napkins", 
        "Party Plates", 
        "Speakers", 
        "Music System", 
        "Cups", 
    ]; 
    itemString; 
    itemList; 
    start; 
    end; 
    helper(itemString) { 
        this.itemList = itemString.split(","); 
        for (let i = 0; i < this.itemList.length; i++) 
            this.itemList[i] = this.itemList[i].trim(); 
        return this.itemList; 
    } 
    model() { 
        return this.partyItems; 
    } 
    setupController(controller, model) { 
        this._super(controller, model); 
        controller.set("helper", this.helper); 
        controller.set("partyItems", this.partyItems); 
        controller.set("itemString", this.itemString); 
        controller.set("itemList", this.itemList); 
        controller.set("start", this.start); 
        controller.set("end", this.end); 
    } 
} 

app/controllers/party.js

import Ember from "ember"; 
import { 
    objectsAt, 
    removeObject, 
    removeObjects, 
    slice, 
    reverseObjects, 
    setObjects, 
    reject, 
} from "@ember/array"; 
  
export default Ember.Controller.extend({ 
    actions: { 
        getItems(itemString) { 
            this.itemList = this.helper(itemString); 
            for (let i = 0; i < this.itemList.length; i++) 
                this.itemList[i] = parseInt(this.itemList[i]); 
            let tempItems = this.partyItems.objectsAt(this.itemList); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++)  
            { 
                str += tempItems[i] + "\n"; 
            } 
            alert(str); 
        }, 
        removeItems(itemString) { 
            this.itemList = this.helper(itemString); 
            if (this.itemList.length == 1) 
                this.partyItems.removeObject(this.itemList[0]); 
            else this.partyItems.removeObjects(this.itemList); 
            this.set("itemString", ""); 
        }, 
        sliceItems(start, end) { 
            let tempItems = this.partyItems.slice(start, end); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++) 
                str += tempItems[i] + "\n"; 
            alert(str); 
        }, 
        reverseItems() { 
            this.set("partyItems", this.partyItems.reverseObjects()); 
        }, 
        replaceItems(itemString) { 
            this.partyItems.setObjects(this.helper(itemString)); 
        }, 
        findMultiwordItems() { 
            let reqItem = this.partyItems.reject( 
                (item) => item.split(" ").toArray().length == 1 
            ); 
            alert(reqItem); 
        }, 
    }, 
}); 

app/template/party.js

{{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 Items: </label> 
    {{input value=this.itemString}} 
</div> 
<div> 
    <input type="button" id="remove-item" 
        value="Remove Items" 
        {{action 'removeItems' this.itemString}} /> 
</div> 
<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="slice" value="Slice"
        {{action 'sliceItems' this.start this.end}} /> 
</div> 
<br /><br /> 
<div> 
    <label>Enter Indices: </label> 
    {{input value=this.itemString}} 
</div> 
<div> 
    <input type="button" id="get-item" value="Get Items"
           {{action 'getItems' this.itemString}} /> 
</div> 
<br /><br /> 
<div> 
    <label>Enter Items: </label> 
    {{input value=this.itemString}} 
</div> 
<div> 
    <input type="button" id="replace-item" 
        value="Replace Items"
        {{action 'replaceItems' this.itemString}} /> 
</div> 
<br /><br /> 
<input type="button" id="reverse-items" value="Reverse"
       {{action 'reverseItems' }} /> 
<br /><br /> 
<input type="button" id="find-items" value="Find" 
       {{action 'findMultiwordItems' }} /> 
{{outlet}}