Top Ember.JS Interview Questions and Answers
by Sachin, on Jul 20, 2022 8:11:35 PM
Q1. What is Ember.js?
Q2. What is Ember JS used for?
Q3. What is the prime task performed by controllers in Ember JS?
Decorating the model which is returned by the route is a very essential task that needs to be performed in Ember.
Q4. What is setupController in Ember?
Q5. What is outlet in Ember?
Q6. What is the core concept of Ember.js?
- Store: This is a central repository and cache of all records available in an application. Controller and admin can access it.
- Models: It specifies a class which defines the data of properties and behavior.
- Records: It specifies an instance of a model which contains loaded information from a server.
- Adapter: It is responsible for translating requested records into the appropriate calls.
- Serializer: It is used to translate JSON data into a record object.
- Automatic Caching: It is used for caching.
Q7. What are the main advantages of using Ember.js?
- It is an open source framework. So, it gives developers unlimited access for customizing for desired output.
- Ember.js doesn't require server requests to perform its task.
- DOM is directly updated when a user comes in contact with the browser or press any button over there.
Q8. What are the features of Ember.js?
- It contains HTML and CSS at the core of the development model.
- It provides the instance initializers.
- It can be used to manage the URL.
Q9. What is a router in Ember.js?
A router is a core feature of Ember.js. It is used to translate the URL into the series of templates and also represent the state of an application. Every URL has a corresponding route object that controls what is visible to the user. It matches the current URL to other routes which are used for loading the data, displaying the templates and set up an application state.
Q10. What are the main components of Ember.js?
- The Router
Q11. Explain the architectural structure of Ember.js applications?
- Models: Models define the data that is used in an application.
- Controllers: Controllers are used to modifying the queries, edit the data and provide user interactions.
- Views: Views are used to display the data and capture the user actions to be repeated easily if needed in the future.
Q12. What are the benefits of using Ember.js?
- It is open-source in nature which gives developers unlimited access when it comes to customization and desired outcomes
- It doesn’t need server requests to perform its task.
- DOM can directly be updated when a user comes in contact with the browser or press any button over there
Q13. What do you mean by Ember Data?
It is basically considered as a library that keeps all the retrieving records either from the user or from a server. Its responsibility is to update the data and then again save them to the server. In case programmers felt, they can check the errors and redundancy before it is made to save on the server. It can also be used for data backup and other purposes in case the need for the same is realized.
Q14. What are the common functions that you can find in the Ember Package?
- Log Binding
- Type of
- Make Array
Q15. What is Ember Namespace?
Sometimes an object contains the application of a framework. Defining the same object is a daunting job because it cannot be directly accessed. For this purpose, Ember namespace can be used.
Q16. What is an adapter in Ember.js, and why is it used?
In Ember Data, an Adapter is used to determine how data is persisted to a backend data store. Things such as the backend host, URL format, and headers used to talk to a REST API can all be configured in an adapter. For example, the rest adapter is used to deal with JSON APIs, and LSAdapter deals with local storage.
Q17. What do you know about Ember.js structure?
Ember.js follows Models, Views and Controller structure. It is abbreviated as MVC.
- Model: Model is used to define the data which is present and is useful for the developer.
- View: View is used to display the data and also capture the action of the users to use when needed.
- Controller: Controller is used to modifying a query. It also modifies the data and offers user interactions in the most reliable manner.
Q18. What do you know by observers in Ember.js?
Ember supports observing any property which also includes computed properties. Observers are something which contains the behavior that reacts to the changes made in other properties. Observers are used when we need to perform some behavior after binding has finished synchronizing. New ember developers often use observers. Observers are mostly used within the ember framework and for that; computed properties are the appropriate solution. An observer can be set on an object using the following syntax- "ember.observer" Observers in ember are synchronous. They fire as soon as they observe a change in the properties. So, because of this, it is easy to introduce bugs where properties are not yet synchronized.
Q19. Explain the directory structure in Ember.js.
In Ember.js, project structure is also called directory structure. It contains the following files and directories:
- I-app: It contains folders and files for models, components, routes, templates, and styles.
- I-bower_components/ bower.json: It is a dependency management tool which is used in Ember CLI to manage front-end plugins and component dependencies.
- I-config: It contains the environment.js which controls configure settings for your app.
- I-dist: It contains the created output files when we build our app for deployment.
- I-node_nodules/package.json: Directory and files are from npm. Npm is the package manager for node.js.
- Public: The public directory contains assets such as image and fonts.
- Vendor: This directory specifies a location where front-end dependencies that are not managed by Bower go.
- Tests/testem.js: Automated tests for our app go in the test folder, and testing is configured in testem.js.
- Tmp: Ember CLI temporary files live here.
- Ember-cli-build.js: This file describes how Ember CLI should build our app.
Q20. What are the different Template components in Ember.js?
Various template components are potent in Ember.js and are used for specific purposes related to running the code in an error-free manner.
These template components are:
Q21. Which function in Ember.js is used to test whether the value is an array or not?
The isArray function is used to check whether the value is an array or not. It returns true if the passed object is an array or Array-like. The Objects are considered to be Array-like if any of the following are true:
- The object is a native Array
- The object has an objectAt property
- The object is an Object and has a length property