Dojo Interview Questions and Answers

Q1. What is DOJO?
DOJO is an open source JavaScript framework designed for very fast development of JavaScript/AJAX based application and websites having cross platform interdependencies.

Q2. What is the basic structure in Dojo?

Q3. What are  all the features of DOJO.

• Widgets e.g. Menus, Sorted Tables, 2-D vector drawing etc.
• Asynchronous Communication – It is the main feature of AJAX due to which information is exchanged and updated but page is not refreshed.
• Packaging System – It provides modular development of functionality in individual or sub packages.
• Client-Side Data Storage – Dojo Storage provides web-apps to store client side data in browsers.
• Server-Side Data Storage – It implements under dojo.data namespace. Example- Csv Store, Opmi Store, Yahoo Store, Delicious Store, Rdf Store.

Q4. What is Package System in Dojo?
• Dojo consists of JavaScript files
• Package system takes care that only needed files are included
• Each JavaScript file can be named as package dojo.provide(dojo.string)
• By that name the package can be taken in use dojo.require(dojo.string)
• One has not to remember any file or directory names
• Only dojo.js has to be included into HTML document
• That file takes care of initialization of Dojo
• There is a couple of pre packaged builds that consist of different kinds of packages e.g. Widget, event or IO builds.

Q5. What is the difference between dojox, mobile, parser and dojo.parser?
Some of the advanced features of dojo.parser, such as <script type=”dojo/method”> and <script type=”dojo/connect”>, are missing. Basic features are compatible with dojo.parser

Q6. List the advantages of DOJO.

• Regular Expression
• Associative Array
• Object and Classes
• Loosely typed variables

Q7. What is the point in Dojo?
• Dojo bases on the HTML and JavaScript
• Developer has not to use any strange programming language
• Dojo ups abstraction layer in a higher level
• Developer has not to reinvent wheel when starting programming project

Q8. What is Widget Toolkit in Dojo?
• Widget toolkit is also a very noticeable part of Dojo toolkit
• Widget is a user interface object that has a layout and some properties
• In Dojo widgets are HTML+CSS bound by JavaScript
• Dojo has lots of useful widgets e.g. Tabs, sorting table, dialogs

Q9. Do You Know Why Does In Many Of Tests Html Files Have Style=”visibility:hidden;”?
It is to prevent raw HTML rendering result from being shown before dojo&rsquo;s rendering finishes. The visibility will be restored by the initialization code in dojox/mobile/common.

Q9. What Is The Relation Between Ajax And Dojo?

• Dojo is sometimes advertised as AJAX framework
• It is able to make AJAX requests with Dojo
• But the technique of binding is under the abstraction layer that Dojo has.

Q10. What are Application Support Libraries in Dojo?
• Consist of the most interesting routines
• IO package provides routines e.g. for AJAX binding
• DND package provides routines for drag-and-drop operations
• There is also some useful routines in logging, storage and animation packages

Q11. Give some components that comes along with Dojo framework.

• DOJO Tree
• DOJO Button
• DOJO Calendar control
• DOJO Grid
• DOJO List box
• and many more..

Q12. Difference between DOJO and jQuery.

Q13. What are modules in DOJO?
In Dojo, Modules are individual codes that can be loaded separately. They are identified using a string that is similar to the file path where the code is defined. Example: my/module/class.

Q14. Describe Language Libraries in DOJO.
It is the wrapper for common idioms which consist of functional programming API’s
Syntax:dojo.lang.*
Example: dojo.lang.forEach, dojo.lang.map, dojo.lang.assert.

Q15. What are the disadvantages of Dojo?
1.Even if Dojo is nice, beautiful etc, it is quite heavy
2.The documentation is still quite narrow
3.Needs much network
4.Developer depends on the browser support for the Dojo
5.There is no way to hide the Dojo code in case of commercial application

Q16. Write a code for widget in Dojo?

Q17. What are the advantages or benefits of Dojo?

• Associative arrays
• Loosely typed variables
• Regular expressions
• Objects and classes
• Highly evolved date, math, and string libraries
• W3C DOM support in the Dojo

Q18. Tell Us About Language Libraries In Dojo?

• dojo.lang.*
• Wrappers for common idioms
• Functional programming APIs

For Example:

• • dojo.lang.forEach
  • dojo.lang.map
  • dojo.lang.assert

Q19. Explain Whether Dojo Is A Part Of Ajax And Distinguishes Their Roles?
Dojo is not a part of Ajax; it is an open source JavaScript toolkit, designed to ease the quick development of JavaScript or Ajax-based applications and websites. It provides you with lots of custom components like data grid, scroller, calendar, etc. It serves some data-structure mode like collection and array list, and it also provides some advanced API’s like API to make AJAX calls.
While, AJAX is an Asynchronous JavaScript and XML, together they make it possible to make JavaScript function call to your server and trigger a response. They use XMLHttpRequest and XMLHttp response object.

Q20. Mention What Are The Limitations Of Dojo?
Limitation of Dojo are :

• It needs much network
• Developer remains dependent on the browser support for the Dojo
• In the case of commercial application there is no way to hide the Dojo code
• Documentation is quite narrow
• In the case of commercial application there is no way to hide the Dojo code.

Q21. Can You Set The Tab Focus Sequence For Destop Browsers?
Yes, use the tabindex attribute for this purpose. IconItem, IconMenuItem, ListItem, TabBarButton and ToolBarButton all have the tabindex attribute initially set to 0 by default.

Q22. Are Applications Keyboard Accessible On Desktop Browsers?
Yes, except for ScrollableView and SwapView. These widgets require alternative ways to scroll and flip, ex. buttons.