Top 40 UI Developer Interview Questions and Answers [Updated]


User Interface Developers, undoubtedly, belong at the top of the hierarchical chain of the IT industry owing to their complex role and high paying salary. A UI Developer must consider many factors to develop a web application or software. One primary requirement of the job is creativity. A User Interface Developer employs logical thinking and a few psychological concepts to stimulate audio and visual senses to create a software that is understandable, easy to use and pleasing to the eye. The job also includes technical knowledge and skill as the core to designing and developing a software that is not only flawless in design but also informative in the way that it provides the user with the solution he is looking for to deliver the best User Experience. 

Below is a curated list of some of the User Interface Developer questions most frequently asked by the interviewers in a UI Developer Interview process, including Markup languages, HTML, Semantic elements, Scripting, Storage and many other questions covering concepts from a Beginner to an Advanced level.

Most Frequently Asked UI Developer Interview Question and Answers

What is the role of a UI Developer?

Ans : UI Developer is responsible for creating functional User Interfaces that are convenient, meet the user’s needs and are easy to access, understand and interact with to receive or give a response.

What is the difference between a UI Developer and a UX Developer?

Ans: UI Developer is mostly responsible with the appearance and design of the app, the aesthetics. Colours, patterns, designs and other elements that make an application appear attractive to the end user. On the other hand, a UX Developer is responsible for the technicalities that ensure the functioning and expected performance of an app to deliver enhanced user experience.

What is the difference between a UI Developer and Front-end Developer?

Ans : The UI Developers focus on making an application user-friendly and engaging while the Front-end Developers test and work on the client-side interface in detail to ensure its proper functioning.

What kind of skills do you think are crucial for a UI Developer?

Ans : UI Developers must possess two sets of skills:

Hard Skills – HTML, CSS, JavaScript, Wireframing & Prototyping, Coding, Interaction Designing, Visual Communication.

Soft Skills – Curiosity, Analytics, Communication, Logical thinking, Creativity, and Copywriting.

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Name three ways to reduce a page’s load time?

Ans : Page load time can be reduced by trimming down JavaScript parsing, minimizing redirects, and compressing files. 

What is HTML?

Ans : The HyperText Markup Language or HTML is a  markup language that helps create a basic structure for a webpage to display the required content and other elements.

What is Semantic HTML?

Ans : Semantic HTML or Semantic Markup, are tags that classify the text and separate it from other Semantic elements to clarify the intent of the content in the webpage and the webpage itself. 

Explain the difference between the and tags.

Ans : A tag is used to bold the selected words and are mostly for conventional writing formats whereas, the tag stresses on the importance of the words and emphasizes not only the word but also highlights the semantics.  

Name at least three position property attributes.

Ans : Absolute, Fixed, Relative, Inherent and Static are position property attributes.

. Explain the differences between the quartet of position properties: Relative, Absolute, Static, and Fixed.

Ans : Static – an undeclared position for an element automatically files the element as static in the CSS. Static positioning is the default position.  

  • Relative – relative elements’ position can be changed from the current position based on the space you mention. 
  • Absolute – an absolute positioning allows the placement of any page element anywhere you want it by using the position attributes to set a location. 
  • Fixed – a fixed page element is rooted to the same spot even when you scroll up or down.

. Explain Web Accessibility.

Ans : Web Accessibility is a feature that enables the differently-abled persons to comprehend, interact, and navigate the web. 

. What is JavaScript Hoisting?

Ans : In JavaScript, Hoisting allows all declarations to be moved to the top of the scope before code execution, irrespective of where the  functions and variables are declared.

. What is the difference between HTML and XHTML?

Ans : HyperText Markup Language or HTML is SGML based while Extensible HyperText Markup Language XHTML is XML based. All  content in the HTML can be put in the body but it  needs  to be separated into blocks in XHTML. In short, XHTML is more intensive on structure, conditions and format than HTML. 

. Explain the difference between Local Storage, Session Storage, and Cookies.

Ans :

  • Local Storage – Local Storage provides maximum storage and is cleared when a page or private tab is closed but the data does not expire.
  • Session Storage –  In Session Storage, Pages are only stored for the amount of time the browser or tab is open. The data is cleared as soon as the tab or browser is closed. 
  • Cookies – Cookies store activity information on a server for delivering a personalized experience.

. Discuss the differences between a document and a window.

Ans : A Window object is the first object of the DOM hierarchy. A Document object is within the Window object. HTML elements are accessed through the Document object.

. Does HTML require a compiler?

Ans : Compilers are programs that convert a programming language code into machine code. Considering HTML is a Markup language and not a programming language, it does not require a compiler.  

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. How do floats work?

Ans : Floats help navigate elements to the sides and generally include one of the following four values: 

  • Inherited – the parent’s float value is inherited by an element.  
  • None – since no value is defined, the element stands at the default value and doesn’t float. 
  • Left – The element floats completely to the left side of the container. 
  • Right – The element floats completely to the right side of the container. 

. Name three plugins available in the Bootstrap jQuery plugin library.

Ans : The plugins available in the Bootstrap jQuery plugin library include: 

Alert

Affix, Button, Carousel, Collapse, Dropdown, Modal, Popover, Scrollspy, Tab, Tooltip

. What CSS class should be employed to span 14 columns on medium-sized screens, and eight columns on large screens?

Ans : The CSS class: class=”col-md-14 col-lg-8” should be used.  

. How do you verify if a variable is set in PHP?

Ans : To verify if a variable is set the command !isset($var); can be used.  

. When an error is encountered, how do you differentiate between require () and include ()?

Ans : The require () function stops executing the script when an error is encountered but in the include () function the application continues without a fatal error. 

. What is a CSS reset? How do you differentiate it from normalize.css?

Ans : CSS Resets remove all the default styling on the elements in the browser while a Normalize CSS does not remove the default styling settings. 

. What is an AJAX request, and how can an AJAX request be used?

Ans : Asynchronous Java Script And XML or AJAX requests that provide the user the required data. AJAX calls connect with the servers by using XMLHttpRequests to exchange the data.  

. How do you use HTML5 new tags in IE version eight and earlier?

Ans : The new HTML5 tags are not supported by IE7 and IE8. Using HTML5 tags in IE7 or IE8 would cause errors and result in glitches. Instead, html5shiv.js can be used to run the tags in older browsers.

. What are the effects methods used in jQuery?

Ans :Some effects methods used in jQuery include: 

  • show() – the selected elements are displayed by this feature. 
  • hide() – it causes the selected items to be hidden. 
  • toggle() – it is used to check the visibility of the elements and toggles between the show() and hide() for the selected elements.

. List the types of filters in AngularJS.

Ans :The filters used in AngularJS are 

  • number – formats the numeric data
  • currency – formats numbers into the specified currency 
  • date -formats the date into the prescribed format
  • uppercase – converts a string into uppercase
  • lowercase – converts a string into lowercase
  • filter – filters array in the criteria specified
  • orderby – arrays are ordered by expressions 
  • Json – formats JavaScript objects into JSON strings
  • limit – limits an array to a number of elements

. How do you optimize a website’s assets?

Ans : A website’s assets can be optimized in the following ways: 

  • File compression 
  • File concatenation 
  • Offloading assets 
  • CDN hosting 
  • Code refining and reorganizing.

. What does DOCTYPE mean?

Ans :The DOCTYPE determines the HTML type used on a webpage and a browser uses DOCTYPE to determine how the page is to be rendered or displayed.  

. Explain the difference between standards mode and quirks mode.

Ans :Standards mode was invented to adapt to the modern HTML and CSS specifications whereas, in Quirks mode, the body element is the primary element. Quirks mode is for older browsers.

. What are the limitations to XHTML pages?

Ans :One major limitation faced by XHTML is the lack of browser support. Many browsers cannot parse XHTML as XML, making it a less used Markup language.  

. How to make comments without the text being picked up by the browser?

Ans : Comments starting with “*” and ending with “->” are used to prevent a code from being recognized by the browser.

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. What is the difference between linking to an image, website, and an email address?

Ans :

  • Tags are used to link an image. 
  • The anchor tag is used for hyperlinking and the link must be specified in the href attribute. 
  • The href specification “mailto:send@here.com”  is used to link an email address.

. What would you do when a hyperlink or image is displayed incorrectly?

Ans :The following mistakes cause the image or link to be displayed incorrectly: 

. What is the syntax difference between a numbered list and a bulleted list?

Ans :Bulleted lists are accompanied by the unordered list

      tag. Ordered lists are accompanied by

 

. What is meant by a responsive website?

Ans :A website that functions at any screen resolution and on any system or device such as PC, mobile, laptop, etc., and adjusts to a readable size and is understandable by a user is a responsive website. 

. How do you access a get requests URL parameter with Php?

Ans :To access a get request URL parameter, the Php is: $_GET[“turkey”] 

. What are the new elements in HTML?

Ans :The new HTML elements are graphic tags, semantic tags, and multimedia. Semantic tags include figure, header, footer, and mark. Graphic tags include audio and canvas.  

. Is JavaScript a case-sensitive language?

Ans :When writing in JavaScript, a developer is required to follow the consistent variables, function names, capitalization of letters, and other identifiers to avoid errors in functioning.  

. Explain the layout of HTML in detail.

Ans : HTML layout specifies how the webpage is to be arranged. The HTML5 elements used to define the parts of a webpage are 

  • : it defines the header of a document or a section. 
  • : it defines or specifies a section in the document. 
  • : it defines an independent article. 
  • : it defines the footer of the document.

. Write a JavaScript code to find specific objects in an array of objects.

Ans :Use the JavaScript “find” method. The specific objects can be found by using the code given below: 

let customers = [

  { id: 0, name: 'jane' },

  { id: 1, name: 'tim' },

  { id: 2, name: 'maria' }

];

let customer = customers.find(cust => cust.name === 'maria');

console.log(customer);

--> { id: 2, name: 'maria' }

. What are the ways to improve page performance?

Ans. You can follow the following ways to improve the performance of a web page.:-

  • Always clear cache
  • Minimize the size of the images
  • Make the code fit for mobile browsing
  • Compress HTTP
  • Reduce redirects

. How can a new variable be declared in PHP equal to the number 5?

Ans. To declare a new variable in PHP equal to the number 5 is $number = 5;

. Define the Semantic element’s importance?

Ans. The below reasons will let you know about the importance of Semantic elements.:-

  • These elements structure the code and make it more accessible and consistent for users. 
  • If the semantic elements are used by developers, search engines, and other assisting technologies, then the content and the context should be understandable.
  • Also, the semantic elements enhance the code’s readability, making the developer’s work much easier and quicker.

. Distinguish between the elements Inline, Block, and Inline-block.

Ans. 

Inline: The inline elements in HTML do not begin with the new line; instead, they occur in the same line. In this element, we can add some space to the left and right on it instead of adding space to the bottom & top padding to the page. Examples include span, strong, mark, etc. 

Inline-block: The inline-block elements are similar to inline elements, but they allow the spaces on all sides.

Block: The element block will always begin with a new line. It fills both the left and right spaces of the web page by adding padding and margins. Examples of block elements include div, p, etc.

. Define CSS.

Ans. CSS means Cascading Style Sheets which describe the web pages’ styles which consist of fonts, colors, layouts, etc. We can also define variations and layouts for different types of screens. Moreover, CSS is also useful for XML-based markup languages apart from HTML.

. Distinguish between HTML Tags and HTML Elements.

Ans. HTML tags define the format of content and its display on the web browser. These tags include the components like content, open, and ending tags. On the other hand, HTML elements inform the web browser how to display the text. Further, these elements will become tags when we use brackets <>.

. What are the key benefits of CSS?

Ans. The following are a few of the many benefits of CSS. 

  • It offers users good control over the web page layout.
  • The style files under CSS are made independently of the HTML, so the file size will be smaller.
  • Due to less coding, the files will load much faster. Thus, it increases the website speed.
  • It offers to format changes easily.
  • CSS compatible works across devices.
  • It allows a single CSS to replicate through different web pages, reducing development time.

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. What is meant by event bubbling and event capturing?

Ans. Event bubbling is a procedure of event propagation inside the HTML DOM API. As the event is launched, the element bubbles up the DOM tree. Here we call the child node first, then the parent node. On the other hand, event capturing is different from event bubbling. It is the opposite of event bubbling, where the parent node is called first, then the child node.

. Define the use of and tags.

Ans. The tag is an element used to give an Italic look at the text, whereas the tag is an emphasis element that defines the emphasized text.

. What is meant by the CSS Box Model?

Ans. The CSS Box Model is a type of box that wraps the HTML element. It consists of the assets like actual content, borders, margin, padding, etc. It is all about the design and layout that helps develop a web page’s structure and design.

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Kavya works for HKR Trainings institute as a technical writer with diverse experience in many kinds of technology-related content development. She holds a graduate education in the Computer science and Engineering stream. She has cultivated strong technical skills from reading tech blogs and also doing a lot of research related to content. She manages to write great content in many fields like Programming & Frameworks, Enterprise Integration, Web Development, SAP, and Business Process Management (BPM). Connect her on LinkedIn and Twitter.

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Groovy is a subset of the java language and shares a good market in recent times. If any of the java programmers are looking out for a career change, here you go. We are going to design Groovy interview questions and answers under the guidance of the SEO team and Groovy experts. In this Groovy interview questions and answers post, you will be learning the very important questions which are asked by top companies. Kick start your Groovy professional career with the help of frequently asked Groovy interview questions and Answers. 

Most Frequently Asked Groovy Interview Questions

What do you know about JVM (java virtual machine)?

Ans : JVM stands for Java virtual machine and they are considered to be an important component of Groovy runs. So Groovy needs the JVM to perform many java-based tasks. 

What do you mean by Groovy?

Ans : Groovy is basically an object-oriented programming language and it has been a top choice for many programmers to write and execute their Java codes. The reason behind its popularity is its customization features to any extent. And also last but not the least, the best user interface services. So it is very easy to develop applications with the help of the Groovy user interface.

What are the true reasons behind Groovy popularity?

Ans : Here we would like to mention a few reasons behind its popularity among other java programming languages.

  • Groovy can be used for scripting like log configuration.
  • It is not a fully object-oriented programming language.
  • It mainly uses Java libraries and multiple inheritance.
  • It offers native support for various markup languages like HTML (hypertext markup language) and XML (extended markup language). 
  • It has a public modifier.
  • It supports tools like Gradle and Spack 
  • It also consists of tools that support other programs to run. For example Grails and Java

Could you please mention the benefits of using Groovy?

Ans : Below are the primary advantages of using Groovy;

  • Compile and execute with all the java libraries that include a part of the COAT JAVA installation.
  • It offers very light syntax while writing a program
  • Offers several examples in the software center.
  • Less work is required during the time of processing HIPO files as input.

What are the limitations of the Groovy language?

Ans : Here are the few disadvantages of using the Groovy language:

  • Having to use GROOT means not having all the plotting and fitting power associated with ROOT as GROOT is a smaller subset of the ROOTs plotting and fitting.
  • Need to know JAVA which is less common for psychic-based analysis

Explain the concept of thin documentation in Groovy?

Ans : This is a very common issue in almost all object-oriented languages. The real problem behind this inaccuracy is that Groovy doesn’t provide detailed documentation on the projects or code. Therefore you will get limited documentation with no information regarding programming codes or run-time errors

How can you run the script in Groovy?

Ans : Running script is a nit a big deal for many programmers. All the plain scripts are very easy to run on a Groovy, and one good thing is that there is no need for programmers to declare any class or methods which consume extra time. At the beginning of any script, that enables the programmers to use import values. This process is very similar to implementing them in a class. In case you want to declare a function outside the class, you can make use of the command “def

Name a few infrastructures that can be used along with Groovy?

Ans :The following are the name of a few infrastructures that can be used along with Groovy;

  • App servers
  • Servlet (java servlet) containers
  • Databases having JDBC drivers
  • All other java based programs. 

Do you really think that Groovy is a simple language than others if so give reasons?

Ans : Yes, most of the developers agree that Groovy is a simple language to use and code. The reasons are as follows;

  • Users can enjoy a simple declaration of all the arrays, maps as well as ranges. 
  • This makes programmers proceed with multiple tasks and they can expect effective outcomes s

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. Is it possible for you to integrate with other applications that are not based on Java?

Ans : Yes, this is possible. However, only one problem with Groovy integration is that it offers limited features that cannot be used to handle complex programming.

. What are the basic requirements for Groovy?

Ans : The primary requirements that are needed for Groovy are as follows:

  • The Java 1.4 version.
  • The Groovy. Jar 
  • The ASM libraries

. What do you mean by Groovy applications?

Ans : Apache Groovy is one of the powerful approaches used in the different modules. The very first thing that comes to mind is adjoining the different modules of java. It doesn’t matter the size but they can be easily combined with the different Java modules. In addition to this, all the existing java applications can be extended through Groovy very simply. This process also makes it easier to develop java-based applications without any error. There are several other applications available, but they are quite common.

. What are the features Groovy JDK equipped with?

Ans : Below are the common features that Groovy JDK (java development kit) is equipped with;

  • Using Groovy is simple as it does not require any complex things to implement the applications.
  • It doesn’t matter which operating system you are using and what are the components of the server, it is easily made up to perform various tasks as per the requirements.
  • In addition to this, there are other features available to run the application smoothly based on Java. 

. Compare the old version of the Groovy with the new version?

Ans : When it comes to the new version, there are a lot of advanced features that are quite simple to use when compared to the older version. With the help of the new version, it is also possible to stream arrays and objects of object-oriented methods used in the older version. In addition to this, a lot of run time errors have been eliminated at various stages and commands also have been improved for smooth operations.

. Suppose you are running something on Groovy, is it possible for you to add any data or for the classpath?

Ans : The answer would be yes it is possible. To perform this task, a $classpath variable can be considered. Some programmers also build the $HOME- -> a.groovy – ->lib directory for this. It can simply be defined in the $HOME and users can keep up the pace at every stage

. What do you know about listeners and closures in Groovy?

Ans : Groovy does not support all types of asynchronous inner classes. Users need to be more conscious about the class that they are going to use while defining the functions. In the Groovy also, you will get to see two different types of classes, firstly listeners. In the listeners, the closures can be considered as an adapter for the listener that offers no limit for the inner class implementations. Whereas the closures are nothing but a process of determining the actions that are extremely easy to use.

. Is there any limit on appending the jars that are available in the groovy?

Ans : No there is no such limit, programmers can make them available in any number whenever they need them.

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. What is the importance of using ExpendoMeta class in Groovy?

Ans : Expendometa class is a powerful option available in Groovy. With the help of this class, the programmers can able to add and consider properties, constructors, methods, and operations to perform various tasks. By default, ExpendoMeta cannot be inherited and users need to call it whenever they required it. 

The following command is used to declare ExpendoMeta class;

ExpandoMetaClass.enabledglobally()”.

. What factors do you need to take care of while declaring Groovy strings?

Ans : Below are the important factors you need to take care of them;

  • All the expressions which are used in Groovy must be declared using the ${}.
  • The next step is, it should be joined by double-quotes. 
  • However, if the strings are regular, you can use a single quote.
  • The Square bracket [] in the Groovy can be applied in a very general manner.
  • Also, users need to remember one thing that is Groovy string is also known as Gstring.

. In Groovy, from the database how can you derive a single class?

Ans : This can be done with the help of the following command;

Println “Row; ColumnA = $”.

There is another option that is also available to do so manually but it is a complex one and there are certain sets of modifications required which will never be performed by programmers

. What is querying in Groovy? Why there is a need for it?

Ans : Querying in Groovy is basically an approach that is used to detect whether the set of commands is compatible with the required operations or not. Also, it can be considered when users need to verify or cross-examine something. The Groovy is an approach that has support for the various queries and the same thing can be handled. The primary task of Querying in Groovy is to ensure error-free outcomes under every situation.

. What does the AST stand for?

Ans : AST in Groovy stands for Abstract syntax trees.

. Explain the AST builder in Groovy?

Ans : In DSL (data syntax language), the codes, as well as strings, are extremely useful factors. This type of task is reliable and there is nothing much that the users need to do. While building AST, sometimes this process might take several hours that depend on the exact number of tasks that are under a tree structure and how they are to be handled.

. Can we include one Groovy script into another Groovy?

Ans : Yes, it is possible. To perform this operation, you need to follow the below codes.

Evaluate(new file (“../tools/Tools.groovy”))

Always remember one thing, place the code on the top of the script for copying the contents.

. What do you mean by Groovysh?

Ans : Many a time while developing codes programmers have to go through a complex when it comes to evaluating classes, expressions, as well as running the experiments. Groovysh is considered to be a powerful command-line application that makes sure of easy access to the same. Groovysh is used at many stages and the good thing is programmers can call it directly. 

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. How could you retrieve a single value from a database using the Groovy?

Ans : The following are the command is used to retrieve a single value from a database using the Groovy;

row = sql.firstRow ('select columnA, column from tableName')

println "Row: columnA = $ {row.columnA} and column = ${row.columnB}"

wing are the command is used to retrieve a single value from a database using the Groovy;

. Explain how you can query in Groovy with code example?

Ans : Let’s have a look into a simple example where we can query the database in Groovy:

import groovy.sql.sql

sql = Sql.newInstance ('jdbc: jtds: sqlserver://serverName/dbName-Class;domain=domainName','username','password','net.sourceforge.jtds.jdbc.driver')

sql.eachRow ('select * from tableName') {print "$it.id--${it.firstName} –"  }

. Explain GroovyDoc comment?

Ans : Like other multiline comments, Groovydoc comments are multiline but it starts with a /** and ends with */. These comments are related to

  • Type definitions (classes, interfaces, enums, and annotations).
  • Fields and properties definition.
  • Methods definitions.

. Explain the bitwise operators in Groovy?

Ans : Bitwise operators in Groovy can be implemented on a BYTE or an INT a return and INT. There are four types of bitwise operators in Groovy;

  • &: bitwise “and”
  • I : bitwise “or”
  • A : bitwise “xor”
  • ~ : bitwise negation

. When “propertymissing(string) “ method is called?

Ans : The propertymissing(string) method is called when no getter method for a given property can be detected by the Groovy runtime.

nal thoughts:

As per the latest reports, an average salary for any Groovy developer earns Rs. 8, 00, 000, and the salary will increase for an experienced Groovy developer. Groovy is the popular choice of Java program due to its less complexity and coding. In this post, we have listed very important Groovy interview questions with Answres under the supervision of Groovy experts. The companies like PWC, IBM, TCS, Amazon, Facebook, and Instagram are showing keen interest to hire Groovy developers 

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As a Senior Writer for HKR Trainings, Sai Manikanth has a great understanding of today’s data-driven environment, which includes key aspects such as Business Intelligence and data management. He manages the task of creating great content in the areas of Digital Marketing, Content Management, Project Management & Methodologies, Product Lifecycle Management Tools. Connect with him on LinkedIn and Twitter.

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