Friday, February 24, 2017

Joomla - Overview

Joomla is an open source Content Management System (CMS), which is used to build websites and online applications. It is free and extendable which is separated into front-end and back-end templates (administrator). Joomla is developed using PHP, Object Oriented Programming, software design patterns and MySQL (used for storing the data).

Joomla - Installation

System Requirements for Joomla 3.x

  • Database − MySQL 5.1 +
  • Web Server
    • WAMP (Windows)
    • LAMP (Linux)
    • XAMP (Multi-platform)
    • MAMP (Macintosh)
    • Nginx
    • Microsoft IIS

Joomla - Architecture

Joomla is a Model-View-Controller web application. In this chapter, we are going to discuss about the architectural style of Joomla. The following diagram shows the architecture of Joomla.

Joomla - Control Panel

The Control Panel provides default features and functions of Joomla to access through clickable icons, menu bar etc. When you login to the Joomla administrative panel, you will get the screen as shown below. Important icons of control panel and their functions are marked in the following screen −

Joomla - Toolbar

In this chapter we will study about the various toolbar options in Joomla. Given below is a list of toolbars −
  • Article Manager Toolbar
  • Category Manager Toolbar
  • Media Manager Toolbar
  • Menu Manager Toolbar
  • Module Manager Toolbar

Joomla - Menus

Menu manager allows creating custom menus for your website and allows navigation through your website.
Step (1) − Click on MenusMenu Manager in Joomla administrator, you will get the following screen −

Joomla - Content Menu

In this chapter, we will study about menus present under the Joomla content. A drop-down menu is displayed when you click on Content Menu.

Joomla - Components Menu

In this chapter, we will study about Components Menu in Joomla. Click on Components Menu, a dropdown menu as shown below will be displayed −

Joomla - Extensions Menu

In this chapter, we will study about Extensions Menu in Joomla. Click on Extensions, a dropdown menu as shown below will be displayed −

Joomla - Help Menu

In this chapter, we will study about menus present in the Help Menu in Joomla. Click on Help, a dropdown menu as shown below will be displayed −

Joomla - Create Menus

In this chapter, we will study the step-by-step procedure of how to Create Menus in Joomla. Menus are the important part and help to navigate through your website easily.

Create Menus

Here are a few simple steps to create menus in Joomla.
Step (1) − Click MenusMenu ManagerAdd New Menu as shown below.

Joomla - Adding Menu Items

In this chapter, we will study the step-by-step procedure of how to add new menu items in Joomla. Menu items can be created in the main menu (menu1), which we have already created in chapter Joomla - Create Menus.

Joomla - Modify Menu Items

In this chapter we will study the simple steps to modify menu items in Joomla. You can learn how to create menu in the chapter Joomla − Create Menu. You can also learn how to add menu items in a menu bar in the chapter Joomla − Adding Menu Items.
Step (1) − Click on MenusMenu1 (Menu1 was created in the chapter Joomla - Create Menu) as shown below.

Joomla - Creating Submenus

In this chapter, we will study about Creating Submenus in Joomla step by step. Submenu is a menu accessed from a general menu, it can be either shown as one menu with more than two levels or as separate menu modules.

Joomla - Create Modules

In this chapter, we will study about Creating Modules in Joomla. Modules are the extensions which are flexible and lightweight and useful for page rendering.

Create Modules

Following are the simple steps to create modules in Joomla.
Step (1) − Create a folder called mod_firstmodule in your Joomlamodules folder.

Joomla - Breadcrumb Module

In this chapter, we will study about Breadcrumb Module in Joomla. A Breadcrumb is used to display the hierarchical representation of the navigation links so that the users can easily understand where they are in the website and allow them to navigate back.

Joomla - Feed Display Module

In this chapter, we will study about Feed Display Module in Joomla. Feed Display Module is used to show the RSS News Feeds from a website. It is a way to provide user with the updated content from other resources.

Joomla - Footer Module

In this chapter, we will study about Footer Module in Joomla. Footer displays the information of Joomla license and the copyright of the website.

Footer Module

Following are the simple steps to edit an existing Footer Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator. After clicking on Module Manager you will get the following screen.

Joomla - Latest News Module

In this chapter, we will study about Latest News Module in Joomla. Latest News Module is used to display the most recent published article in a list.

Latest News Module

Following are the simple steps to edit an existing Latest News Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator control panel. Following screen will be displayed −

Joomla - Search Module

In this chapter, we will study about Search Module in Joomla. Search Module is used to display a search box, where the user types a particular name to search the website.

Search Module

Following are the simple steps to edit an existing Search Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator control panel, you get the following screen −

Joomla - Random Image Module

In this chapter, we will study about Random Image Module in Joomla. Random Image Module is used to display the images randomly from the selected directory.

Random Image Module

Following are the simple steps to edit an existing Random Image Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator, the following screen will be displayed −

Joomla - Who's Online Module

In this chapter, we will study about Who's Online Module in Joomla. This module helps to display the user's information who are accessing the website.

Who's Online Module

Following are the simple steps to edit an existing Who's Online Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator, the following screen will be displayed.

Joomla - Syndicate Module

In this chapter, we will study about Syndicate Module in Joomla. Syndicate module helps in creating an RSS Feed link for the page. It allows creating a Newsfeed by the user for the current page.

Syndicate Module

Following are the simple steps to edit an existing Syndicate Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator,the following screen will be displayed.
Joomla Syndicate Module Step (2) − Next, click on New button and the following screen will get displayed. On this page, click on the Syndication Feeds.
Joomla Syndicate Module Step (3) − Next, click on Syndication Feeds, the existing Syndicate module will get displayed as shown below.
Joomla Syndicate Module By default, the Module tab is displayed. Below, we have mentioned the details of the fields present in the Module tab.
  • Title − Displays the title of Module.
  • Display Text − Text gets displayed by selecting option such as Yes or No.
  • Text − The entered text will get displayed next to the icon when the Display Text is set as Yes. If the field is left empty then it will display a default text.
  • Feed Format − The syndication Feed format is selected i.e. RSS 2.0 or Atom 1.0.
  • Show Title − Displays the title of the module in the front end.
  • Position − It will select the position of the module to be displayed.
  • Status − It displays the status of the article such as Published, Unpublished and Trashed.
  • Start Publishing − It will start publishing at the assigned date and time.
  • Finish Publishing − It will finish publishing on the assigned date and time.
  • Access − It allows access only to selected users from the dropdown list such as Guest, Public, Super Users, Registered and Special option to view the items.
  • Ordering − Displays the dropdown of all modules present in the position.
  • Language − It specifies the language of the site. It provides either ALL or English (UK) options.
  • Note − It is used to enter the text information.
Step (4) − Click on the Menu Assignment tab, you will get the screen as shown below.
Joomla Syndicate Module
  • Module Assignment − Select the option to view the item from the dropdown list such as on all pages, no pages, only on the pages selected or on all pages except those selected.
  • Menu Selection− After selecting the option only on the pages selected or on all pages except those selected, it will display all menu items present in Joomla. It will allow assigning module to some and not all pages.
Step (5)Module Permissions tab has three action to choose from. It manages the setting of module permission for the user groups as shown in the following screen.
Joomla Syndicate Module
  • Delete − It allows users in group to delete the content present in the module.
  • Edit − It allows users in group to edit the content present in the module.
  • Edit State − It allows users in the group to change the state of content present in the module.
Step (6) − The Advanced tab is used to do the advanced settings of the Syndicate. The advanced tab screen is shown below.
Joomla Syndicate Module
  • Alternative Layout − Selects the layout to use for this module, which you have already defined as one or more layouts for module in Joomla or template.
  • Module Class Suffix − Setting this parameter causes Joomla to either add a new CSS class or modify the existing CSS class for the div element for this specific module.
  • Caching − Caches the content of the module. Use Global is used to cache settings from global configuration. No Caching is used, whether to cache the content of the module or not.
  • Cache Time − Specifies the time in minutes before the module is re-cached.
  • Module Tag − Specifies the HTML tag for the modules.
  • Bootstrap Size − Selects width of the module built in bootstrap.
  • Header Tag − Modules uses the HTML header tags.
  • Header Class − Optional CSS classes are added in the module header.
  • Module Style − Overrides the template style for its position.

Toolbar

Following are the details about the function tabs present on the toolbar of Syndicate module.
  • Save − Saves your modules.
  • Save & Close − Saves the modules and will close the current screen.
  • Save & New − Saves the modules and opens a new creating module screen.
  • Cancel − Cancels the created modules in Joomla.

Joomla - Donation Module

In this chapter, we will study about Donation Module in Joomla.

Donation Module

Following are the simple steps to edit an existing Donation Module in Joomla.
Step (1) − Click ExtensionModule Manager in Joomla administrator, the following screen will be displayed.

Joomla - System Settings

The Global Configuration is used for configuring Joomla site with your personal settings. To access the system settings, just follow the following steps −
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Media Settings

In this chapter, we will study about Joomla Media Settings. Joomla Media Settings help to configure the global media files options such like file format, MIME specifications, upload of files, size of files etc.

Joomla Media Settings

Following are the simple steps used to set the Joomla media options −
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Language Manager

In this chapter, we will study about Joomla Language Manager. The Joomla language manager option is used to set the Native Title, Language Code, SEF Prefix, and Image Prefixes of the installed or to be installed languages.

Joomla - Private Messages

The messaging system allows to send messages to the back- end users of Joomla. You can send, read, write and delete messages.
Step (1) − You can create a new private message as shown in the screen below. Go to ComponentsMessagingNew Private Message to write a new private message.

Joomla - Mass Emailing

Mass Mail is used for sending emails to the group of registered users. Users can be selected based on groups.
Step (1) − To use this feature, go to UsersMass Mail Users as shown in the screen below.

Joomla - Cache Management

In this chapter, we will study about Joomla Cache Manager. You can install the cache controller plug-in which helps to improve the performance of Joomla. You can also turn off the cache on the particular pages and component.

Joomla - Users Setting

In this chapter, we will study about Joomla Users Setting. It gives options on how to configure the new users and provides various options that help restrict new users from providing unwanted details.

Joomla Users Setting

Following are the simple steps used for to set the Joomla users setting.
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Debug

In this chapter, we will study about Debug in Joomla. By enabling the debug mode it helps to troubleshoot the various issues of Joomla. It shows details of how Joomla is rendering Session Data, Profile Information, Memory Usage and Database Queries.

Joomla - Template Manager

In this chapter, we will study about Template Manager in Joomla. It manages the various templates that are used in the website. The templates can be used without changing the content structure of the website.

Template Manager

Following are the simple steps to edit the Template Manager in Joomla.
Step (1) − Click ExtensionsTemplate Manager as shown below.

Joomla - Customize Template

In this chapter, we will study about Template Customize Manager in Joomla. The Customize template allows editing or creating new files in the template.

Customize Template

Following are the simple steps to customize the template in Joomla.
Step (1) − Click ExtensionsTemplate Manager as shown below.

Joomla - Adding Template

In this chapter, we will study how to add / install Template in Joomla.

Adding Template

Following are the simple steps to add / install template in Joomla.
Step (1) − Click on ExtensionsExtension Manager as shown below.

Joomla - Creating Template

In this chapter, we will study how to create a template in Joomla.

Creating Templates

Following are the simple steps to create templates in Joomla −
Step (1) − Create a folder called MyFirstTemplate inside your JoomlaTemplates folder. Inside MyFirstTemplate folder, create 2 more folders named as images and CSS to save all the images and CSS files.

Joomla - Customize Logo

In this chapter, we will study about how to Customize Logo in Joomla. You can add the logo for your web sites and customize it as per your need.

Joomla Customize Logo

Following are the simple steps used to set the customize logo in Joomla −
Step (1) − Click on ExtensionsTemplate Manager.

Joomla - Category Management

In this chapter, we will study about Category Management in Joomla. Category Manager is used to create categories for the article which allow grouping your content better.

Category Management

Following are the simple steps to add new category manager in Joomla.
Step (1) − Click on Category Manager in Control Panel as shown below.

Joomla - Adding Content

In this chapter, we will study how to add content on the Joomla website.

Adding Content

Following are the simple steps to add content in Joomla.
Step (1) − Click on ContentArticle ManagerAdd New Article as shown below.

Joomla - Formatting Content

In this chapter, we will study how to format content on the Joomla website.

Formatting Content

Following are the simple steps to format content in Joomla −
Step (1) − Click on Article Manager in Control Panel as shown below.

Joomla - Article Metadata

In this chapter, we will study about Article Metadata in Joomla. Metadata describes details of the article in short. It makes it easy to work with a particular data.

Joomla - Article Metadata

Following are the simple steps used to set the Joomla article metadata −
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Adding Banners

In this chapter, we will study about Adding Banners in Joomla. It displays the active banners and allows you to use different banners for advertising on webpage.

Adding Banners

Following are the simple steps to add Banners in Joomla.
Step (1) − Click ComponentsBannersBanners in joomla administrator, you will get the following screen.

Joomla - Adding Contacts

In this chapter, we will study about Adding Contacts in Joomla. It stores the contact details of the company.

Joomla Adding Contacts

Following are the simple steps used to set the Joomla contacts.
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Adding News Feed

In this chapter, we will study about Adding News Feed in Joomla.

Joomla Adding News Feed

Following are the simple steps used to add news feed.
Step (1) − Go to SystemGlobal Configuration as shown in the following screen.

Joomla - Adding Forum

In this chapter, we will study about Adding Forum in Joomla. We can install the forum extension in Joomla to share or discuss ideas and views on particular issues.

Joomla Adding Forum

Following are the simple steps used to set the Joomla Adding Forum.
Step (1) − Click on Install Extensions option in Joomla.

Joomla - Adding Web Links

In this chapter, we will study about Adding Web Links in Joomla. It allows you to insert, remove and edit the links to another webpage in Joomla.

Adding Weblinks

Following are the simple steps to add Weblinks in Joomla −
Step (1) − Click ComponentsWeblinksLinks in Joomla administrator. After clicking on Links, you will get the following screen.

Joomla - Plugin Manager

In this chapter, we will study about Plugin Manager in Joomla. It helps you enable and disable Joomla Plugins. This adds the unique features to an existing web site.

Joomla - Extensions Manager

In this chapter, we will study about Extensions Manager in Joomla. We can install different types of extensions to extend the functionality of the site.

Joomla Extensions Manager

Following are the simple steps used to set the Joomla Extensions Manager.
Step (1) − Click on Install Extensions option in Joomla.

Joomla - Website Backup

In this chapter, we will study about Website backup in Joomla. It allows backup of files, folders and re-opens it in Joomla.

Website Backup

Following are the simple steps used to backup the website in Joomla −
Step (1) − Click on SystemGlobal Configuration in Joomla administrator. You will get the following screen.

Joomla - Website SEO

In this chapter, we will study about Website SEO in Joomla. SEO (Search Engine Optimization) is about optimizing a website for search engine. It helps search engines find and rank your site higher than the other sites in response to a search query.

Joomla - Interview Questions

Dear readers, these Joomla Interview Questions have been designed specially to get you acquainted with the nature of questions you may encounter during your interview for the subject of Joomla. As per my experience good interviewers hardly plan to ask any particular question during your interview, normally questions start with some basic concept of the subject and later they continue based on further discussion and what you answer:

Joomla - Quick Guide

Joomla - Overview

Joomla is an open source Content Management System (CMS), which is used to build websites and online applications. It is free and extendable which is separated into front-end and back-end templates (administrator). Joomla is developed using PHP, Object Oriented Programming, software design patterns and MySQL (used for storing the data).

Joomla - Useful Resources

The following resources contain additional information on Joomla. Please use them to get more in-depth knowledge on this.

Discuss Joomla

Joomla is an open source Content Management System (CMS), which is used to build websites and online applications. It is free and extendable which is separated into front-end templates and back-end templates (administrator).

JavaScript - Overview

What is JavaScript ?

Javascript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side script to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.

JavaScript - Syntax

JavaScript can be implemented using JavaScript statements that are placed within the <script>... </script> HTML tags in a web page.
You can place the <script> tags, containing your JavaScript, anywhere within you web page, but it is normally recommended that you should keep it within the <head> tags.

Enabling JavaScript in Browsers

All the modern browsers come with built-in support for JavaScript. Frequently, you may need to enable or disable this support manually. This chapter explains the procedure of enabling and disabling JavaScript support in your browsers: Internet Explorer, Firefox, chrome, and Opera.

JavaScript - Placement in HTML File

There is a flexibility given to include JavaScript code anywhere in an HTML document. However the most preferred ways to include JavaScript in an HTML file are as follows −
  • Script in <head>...</head> section.
  • Script in <body>...</body> section.
  • Script in <body>...</body> and <head>...</head> sections.
  • Script in an external file and then include in <head>...</head> section.

JavaScript - Variables

JavaScript Datatypes

One of the most fundamental characteristics of a programming language is the set of data types it supports. These are the type of values that can be represented and manipulated in a programming language.
JavaScript allows you to work with three primitive data types −

JavaScript - Operators

What is an operator?

Let us take a simple expression 4 + 5 is equal to 9. Here 4 and 5 are called operands and ‘+’ is called the operator. JavaScript supports the following types of operators.

JavaScript - if...else Statement

While writing a program, there may be a situation when you need to adopt one out of a given set of paths. In such cases, you need to use conditional statements that allow your program to make correct decisions and perform right actions.

JavaScript - Switch Case

You can use multiple if...else…if statements, as in the previous chapter, to perform a multiway branch. However, this is not always the best solution, especially when all of the branches depend on the value of a single variable.

JavaScript - While Loops

While writing a program, you may encounter a situation where you need to perform an action over and over again. In such situations, you would need to write loop statements to reduce the number of lines.
JavaScript supports all the necessary loops to ease down the pressure of programming.

JavaScript - For Loop

The 'for' loop is the most compact form of looping. It includes the following three important parts −
  • The loop initialization where we initialize our counter to a starting value. The initialization statement is executed before the loop begins.

JavaScript for...in loop

The for...in loop is used to loop through an object's properties. As we have not discussed Objects yet, you may not feel comfortable with this loop. But once you understand how objects behave in JavaScript, you will find this loop very useful.

JavaScript - Loop Control

JavaScript provides full control to handle loops and switch statements. There may be a situation when you need to come out of a loop without reaching its bottom. There may also be a situation when you want to skip a part of your code block and start the next iteration of the loop.

JavaScript - Functions

A function is a group of reusable code which can be called anywhere in your program. This eliminates the need of writing the same code again and again. It helps programmers in writing modular codes. Functions allow a programmer to divide a big program into a number of small and manageable functions.

JavaScript - Events

What is an Event ?

JavaScript's interaction with HTML is handled through events that occur when the user or the browser manipulates a page.
When the page loads, it is called an event. When the user clicks a button, that click too is an event. Other examples include events like pressing any key, closing a window, resizing a window, etc.

JavaScript and Cookies

What are Cookies ?

Web Browsers and Servers use HTTP protocol to communicate and HTTP is a stateless protocol. But for a commercial website, it is required to maintain session information among different pages. For example, one user registration ends after completing many pages. But how to maintain users' session information across all the web pages.

JavaScript - Page Redirection

What is Page Redirection ?

You might have encountered a situation where you clicked a URL to reach a page X but internally you were directed to another page Y. It happens due to page redirection. This concept is different from JavaScript Page Refresh.

JavaScript - Dialog Boxes

JavaScript supports three important types of dialog boxes. These dialog boxes can be used to raise and alert, or to get confirmation on any input or to have a kind of input from the users. Here we will discuss each dialog box one by one.

JavaScript - Void Keyword

void is an important keyword in JavaScript which can be used as a unary operator that appears before its single operand, which may be of any type. This operator specifies an expression to be evaluated without returning a value.

JavaScript - Page Printing

Many times you would like to place a button on your webpage to print the content of that web page via an actual printer. JavaScript helps you to implement this functionality using the print function of window object.
The JavaScript print function window.print() prints the current web page when executed. You can call this function directly using the onclick event as shown in the following example.

JavaScript - Objects Overview

JavaScript is an Object Oriented Programming (OOP) language. A programming language can be called object-oriented if it provides four basic capabilities to developers −
  • Encapsulation − the capability to store related information, whether data or methods, together in an object.

JavaScript - The Number Object

The Number object represents numerical date, either integers or floating-point numbers. In general, you do not need to worry about Number objects because the browser automatically converts number literals to instances of the number class.

JavaScript - The Boolean Object

The Boolean object represents two values, either "true" or "false". If value parameter is omitted or is 0, -0, null, false, NaN, undefined, or the empty string (""), the object has an initial value of false.

Syntax

Use the following syntax to create a boolean object.
var val = new Boolean(value);

JavaScript - The Strings Object

The String object lets you work with a series of characters; it wraps Javascript's string primitive data type with a number of helper methods.

JavaScript - The Arrays Object

The Array object lets you store multiple values in a single variable. It stores a fixed-size sequential collection of elements of the same type. An array is used to store a collection of data, but it is often more useful to think of an array as a collection of variables of the same type.

JavaScript - The Date Object

The Date object is a datatype built into the JavaScript language. Date objects are created with the new Date( ) as shown below.
Once a Date object is created, a number of methods allow you to operate on it. Most methods simply allow you to get and set the year, month, day, hour, minute, second, and millisecond fields of the object, using either local time or UTC (universal, or GMT) time.

JavaScript - The Math Object

The math object provides you properties and methods for mathematical constants and functions. Unlike other global objects, Math is not a constructor. All the properties and methods of Math are static and can be called by using Math as an object without creating it.

Regular Expressions and RegExp Object

A regular expression is an object that describes a pattern of characters.
The JavaScript RegExp class represents regular expressions, and both String and RegExp define methods that use regular expressions to perform powerful pattern-matching and search-and-replace functions on text.

JavaScript - Document Object Model or DOM

Every web page resides inside a browser window which can be considered as an object.
A Document object represents the HTML document that is displayed in that window. The Document object has various properties that refer to other objects which allow access to and modification of document content.

JavaScript - Errors & Exceptions Handling

There are three types of errors in programming: (a) Syntax Errors, (b) Runtime Errors, and (c) Logical Errors.

Syntax Errors

Syntax errors, also called parsing errors, occur at compile time in traditional programming languages and at interpret time in JavaScript.
For example, the following line causes a syntax error because it is missing a closing parenthesis.
<script type="text/javascript">

JavaScript - Form Validation

Form validation normally used to occur at the server, after the client had entered all the necessary data and then pressed the Submit button. If the data entered by a client was incorrect or was simply missing, the server would have to send all the data back to the client and request that the form be resubmitted with correct information.

JavaScript - Animation

You can use JavaScript to create a complex animation having, but not limited to, the following elements −
  • Fireworks
  • Fade Effect
  • Roll-in or Roll-out
  • Page-in or Page-out
  • Object movements

JavaScript - Multimedia

The JavaScript navigator object includes a child object called plugins. This object is an array, with one entry for each plug-in installed on the browser. The navigator.plugins object is supported only by Netscape, Firefox, and Mozilla only.

JavaScript - Debugging

Every now and then, developers commit mistakes while coding. A mistake in a program or a script is referred to as a bug.
The process of finding and fixing bugs is called debugging and is a normal part of the development process. This section covers tools and techniques that can help you with debugging tasks..

JavaScript - Image Map

You can use JavaScript to create client-side image map. Client-side image maps are enabled by the usemap attribute for the <img /> tag and defined by special <map> and <area> extension tags.
The image that is going to form the map is inserted into the page using the <img /> element as normal, except that it carries an extra attribute called usemap.

JavaScript - Browsers Compatibility

It is important to understand the differences between different browsers in order to handle each in the way it is expected. So it is important to know which browser your web page is running in.
To get information about the browser your webpage is currently running in, use the built-in navigator object.