I am a UI developer. Having more then 12 years experience with industry. Recently for a better Career growth, I decided to hack a CMM Level 5 company interview. For this reason I did started my preparation and keep attending several technical interviews. My good luck nearly after 45 days I got selected in Infosys. During this period to grab my dream job I applied a trick. From each interview I did collected all UI Developer Interview Questions asked by the interviewer. Slowly I found many questions are common. As you know for UI developer we need to learn HTML, CSS, JAVASCRIPT, JQUERY or ANGULARJS or BootStrap.
If you are having the same profile and going to attained a technical interview in this Saturday or Sunday, prepare the below Questions well. I am sure from this list of UI Developer Interview Questions you will must found above 50% similar questions at your interview.
HTML5 Interview Questions
- What are the new elements introduced in HTML5?
- Which browsers support HTML 5?
- What is datalist in HTML 5?
- What are the different advanced form element types in HTML 5?
- What is Canvas in HTML5?
- What is the use of localStorage in html5?
- How to embed a YouTube video using HTML5?
- What is the difference between Canvas & SVG?
- What’s new HTML5 DocType and Charset?
- How can we embed an Audio in HTML5 & what are the audio formats supported by HTML5 Audio Element?
- How to embed a Video file in HTML5?
- What are the different types of storage in HTML5?
- What is Application Cache in HTML5?
- Tell me some new markup elements in HTML5.
- What does a hgroup tag do?
- Which Tags are deprecated in the new version of HTML5?
- In HTML5 how to remove local Storage?
- What is the difference between cookies & HTML5 Local storage?
- How do you make video tag work in Safari version 5?
- What is the use of viewport?
- How to display repeated data in columns using HTML?
CSS3 & BootStrap UI Developer Interview Questions
- What is CSS?
- What are the ways to Apply CSS styles in a HTML documents?
- What is the difference between an ID & CLASS selector in CSS3?
- Explain me the CSS Box Model.
- What is Grouping in CSS3?
- What are Child Selectors in CSS?
- Give some examples of CSS Pseudo-Class.
- What is the use of CSS3 sprites?
- Tell me some New features in CSS3.
- What is the Syntax of Opacity in CSS3?
- What is z-index & How to use it in CSS?
- How to set border radius of a div for IE, FF & Chrome using CSS3?
- What is clearfix hack in CSS?
- What is CSS media queries?
- What are the major CSS properties?
- What is the difference between Fixed Width Layouts & Liquid Layouts?
- What are the difference between Bootstrap 2 & Bootstrap 3?
- What are the different classes in Bootstrap 2 & Bootstrap 3?
- What are the number of Columns in Bootstrap Grid System?
- What are the different Breakpoints in Bootstrap?
- What is the difference Container & Container Fluid?
- Is it possible to load style sheet dynamically? If yes then how?
JAVASCRIPT Interview Questions
- What are the different data types in JavaScript?
- How to Create an Object, Properties & Methods using JavaScript?
- What is closures in JavaScript?
- Is JavaScript is case sensitive?
- What is the difference between “==” & “===” in JavaScript?
- How to comment in JavaScript?
- How to know Checkbox Status using JavaScript?
- How to Create Array using JavaScript?
- What isNaN function does in JavaScript?
- How to Change Style or Class of an element using JavaScript?
- What is Prototypes in JavaScript?
- Tell me the difference between Undefined & Null?
- Why we use splice() Method in JavaScript?
- How to debug JavaScript code?
- Which debugger you have used to debug JS code?
- What is landscape and portrait? How to set this property?
- How will you get device width?
- How will you know that web page request is came from small screen device/mobile?
JQUERY Interview Questions
- What is the difference between Jquery & JavaScript?
- What you required to Start you first Hello World program using Jquery?
- What is document.ready() method in Jquery?
- How to select all elements in a page using Jquery?
- What are the different type of Selectors available in Jquery?
- Explain me the show & hide methods in Jquery?
- What are the advantages using Jquery?
- What is jQuery noConflict method?
- How do you disable or enable a form element using Jquery?
- How to Change href attribute of an anchor tag using JQuery?
- How to Valid an email using JQuery?
- What is JQuery Selector? Explain me with Example.
- Explain the animate function in JQuery.
- What is jQuery.holdReady() function?
- What is JQuery Ajax method?
- How animate method works in JQuery?
- Can we use two versions of JQuery in the same HTML page?
- What is the difference between attr & prop in JQuery?
- What is minify version of Jquery?
- How to load Jquery from Local if CDN link fails?
- What is the use of JQuery $.extend method?
- What is JQuery $.map method?
- Can I have multiple Jquery document.ready() method in a html page?
- What is the difference between document.ready() & body onLoad() method?
- How do you control SVG using jquery?
- How do you add class using jquery?
ANGULARJS Interview Questions for UI Developer
- What are the key features of AngularJS?
- Does Angular use the JQuery library?
- How to use ng-repeat in AngularJS?
- How to use Filter in AngularJS?
- In AngularJS how will you initialize a select box with options on page load?
- What are the advantages of using AngularJS?
- How to use Controller in AngularJS?
- What are the form Validations AngularJS provides?
- How to create Custom Directive using AngularJS?
- What is 2 way data binding in AngularJS?
- What is the CDN link for AngularJS?
- How to bind MySQL data to HTML5 using AngularJS?
- How to use templateURL in the Directive of AngularJS?
- Is AngularJS supports MVVM with MVC?
- What is routes in AngularJS?
- What is the difference between compile & link functions in AngularJS?
- What is difference between Service & Factory?
- What is the Syntax for creating Custom Directives in AngularJS?
- What is factory? For what purpose it is used?
- What is data-binding and how it is achieved in AngularJS?
Technical Questions
## 1. What is the difference between HTML and XHTML?
HTML (HyperText Markup Language) is the standard language for creating web pages, while XHTML (Extensible HyperText Markup Language) is a stricter version of HTML that adheres to XML syntax. The main differences include:
– XHTML requires that all tags be properly closed.
– XHTML is case-sensitive.
– XHTML documents must have a DOCTYPE declaration.
## 2. Can you explain the box model in CSS?
The CSS box model describes the rectangular boxes generated for elements in the document tree and consists of margins, borders, padding, and the actual content area. Understanding how these components interact is essential for layout design.
– Content: The actual content of the box, where text and images appear.
– Padding: The space between the content and the border, inside the box.
– Border: The area surrounding the padding (if any) and content.
– Margin: The outermost space that separates the box from other elements.
## 3. What are CSS preprocessors, and why are they used?
CSS preprocessors like SASS, LESS, and Stylus extend CSS with features such as variables, nesting, and mixins. They allow developers to write more maintainable and reusable code, which can then be compiled into standard CSS.
## 4. How does the `flexbox` layout work in CSS?
Flexbox is a one-dimensional layout model that allows for responsive design by providing an efficient way to align and distribute space among items within a container. Key properties include:
– `display: flex`: Activates flexbox on a container.
– `flex-direction`: Defines the direction of the flex items (row, column).
– `justify-content`: Aligns items along the main axis (start, center, space-between).
– `align-items`: Aligns items along the cross axis (stretch, flex-start, center).
## 5. What are the differences between class selectors and ID selectors in CSS?
Class selectors are denoted with a period (.), allowing multiple elements to share the same class. ID selectors, marked with a hash (#), are unique and can only be applied to a single element within a page. This affects specificity, with ID selectors having higher precedence over class selectors.
Design Principles
## 1. What is responsive design, and why is it important?
Responsive design is an approach that ensures web applications look and function well on various devices and screen sizes. It is essential for improving user experience, as more users access websites via mobile devices. Techniques include fluid grids, flexible images, and media queries.
## 2. Explain the concept of user-centered design.
User-centered design focuses on understanding users’ needs, preferences, and behaviors throughout the design process. This iterative approach ensures that the final product meets user expectations and promotes usability. Key stages include research, prototyping, testing, and implementation.
## 3. What is accessibility in UI design?
Accessibility refers to designing interfaces that are usable by people with disabilities. This includes considerations for visual impairments, motor difficulties, and cognitive challenges. Common practices involve using semantic HTML, providing text alternatives for images, and ensuring keyboard navigability.
## 4. How do you incorporate feedback into your design?
Incorporating feedback involves gathering insights from users, stakeholders, and team members through surveys, usability tests, and reviews. Analyzing this feedback helps identify pain points and areas for improvement, leading to iterative design adjustments.
JavaScript and Frameworks
## 1. What is the purpose of JavaScript in web development?
JavaScript is a programming language that enables interactive and dynamic content on web pages. It allows developers to manipulate the Document Object Model (DOM), handle events, and communicate with servers via AJAX.
## 2. Can you explain the difference between synchronous and asynchronous JavaScript?
Synchronous JavaScript executes tasks sequentially, blocking code execution until the current task completes. Asynchronous JavaScript allows tasks to run independently, enabling better performance and responsiveness by using callbacks, promises, or async/await syntax.
## 3. What are some common JavaScript frameworks or libraries you have used?
Popular JavaScript frameworks and libraries include React, Angular, and Vue.js. These tools streamline UI development by providing reusable components, state management, and routing solutions.
## 4. What is the Virtual DOM, and how does it work?
The Virtual DOM is a lightweight representation of the actual DOM used by libraries like React. When changes occur, the Virtual DOM updates first, calculating the differences between the current and previous versions. Only the necessary changes are then applied to the real DOM, improving performance and rendering speed.
Problem-Solving Questions
## 1. How do you approach debugging an issue in the UI?
Debugging involves a systematic approach:
– Reproduce the issue: Ensure the problem can be consistently replicated.
– Use developer tools: Inspect elements, check console logs, and monitor network activity.
– Isolate the problem: Simplify the code to pinpoint the source of the issue.
– Test solutions: Implement fixes and retest to confirm resolution.
## 2. Describe a time when you had to work under a tight deadline.
In such scenarios, it is crucial to prioritize tasks based on their impact and feasibility. Effective communication with team members and stakeholders is vital to align expectations. Utilizing agile methodologies can help manage workload and ensure timely delivery.
## 3. How do you handle conflicting feedback from different stakeholders?
Conflicting feedback requires careful consideration of each perspective. Engaging in discussions to understand the underlying motivations can clarify priorities. If necessary, propose solutions that address multiple concerns or offer data-driven insights to support design decisions.
Behavioral Questions
## 1. What motivates you as a UI developer?
Motivation stems from a passion for creating user-friendly interfaces that solve real problems. The continuous evolution of technology and design trends also fuels a desire for learning and growth in the field.
## 2. How do you stay updated with the latest trends in UI development?
Staying updated involves regularly reading industry blogs, participating in online communities, attending webinars, and experimenting with new tools and techniques. Networking with other professionals can also provide valuable insights into emerging trends.
## 3. Describe a successful project you worked on and your role in it.
A successful project could involve collaborating with designers and developers to create a responsive e-commerce website. My role included implementing the UI components, ensuring adherence to design specifications, and optimizing performance for mobile users.
Conclusion
UI developer interviews typically encompass a range of questions that assess technical skills, design principles, problem-solving abilities, and behavioral traits. Preparing thoroughly for these topics can help candidates demonstrate their expertise and fit for the role. By understanding the core concepts and keeping abreast of industry trends, aspiring UI developers can position themselves as valuable assets to any team.