Joomla

The Joomla Table class provides a framework which enables you to do CRUD operations and more on database tables. This class can be used for single record only and it doesn't support SQL operations on multiple records.

Tags are stored in the tags table using a tree hierarchy structure. You can use TagsHelper class which provide access to the tag data.

You can create a new Joomla user in your extension (module, plugin or component) easily. At minimum, you need an email to create new user.

Accessing user information (like name, email, username, registered date) is very simple process in Joomla. The getUser() function of the Factory class returns a reference to the global user object.

Building layout is the most important work of template or website development. It is very easy to build from basic to complicated layout with T4 Layout Builder. T4 Framework is a powerful and advanced responsive template framework for Joomla. It is a modern, flexible and highly customizable framework to build beautiful Joomla websites easier.

This file holds the template for the page. It is used to render the page utilising the setup done by the view object. When no specific layout is requested for a view, Joomla! loads the template in the default.php file.

This is the MVC view object. The job of a view object is to handle the setup work for a view template - selecting a layout, fetching Javascript, generating toolbars, and so on.

The display controller is the main controller file for the component. As the component grows in complexity, a page's controller handles model fetching, form submissions, and so on.

Good coding standards are important in any software development project. These standards are even more important when a large, diverse and worldwide community of developers are contributing to a project.

The range form field type provides a horizontal slider for numeric input. While the default value can be set, there is no indication of the actual value being chosen, just the position of the slider's thumb. It is available from Joomla 3.2 version.

The spacer form field type provides a visual separator between parameter field elements. It is purely a visual aid and no field value is stored.

The tag field type provides a field where you can enter tags, either AJAX or nested. This field type can be used after Joomla 3.1 version.

It draws a progress bar based on Bootstrap. This form field is not an input type. It just creates a progress bar. It was introduced from Joomla 3.2 version.

The number form field type provides a HTML5 text box with arrows. If the field has a value saved, this value is displayed when the page is first loaded. If not, the default value (if any) is used. This field is available from Joomla 3.2.

The sql form field type provides a drop down list of entries obtained by running a query on the Joomla database. If the field has a value saved, this value is selected when the page is first loaded. If not, the default value (if any) is selected.

The subform form field type provides a method for using XML forms inside one another or reuse forms inside an existing form. If attribute multiple is set to true then the included form will be repeatable.

The tel field type defines a field for entering a telephone number. Telephone numbers can be validated using the tel rule and filtered using the tel input filter.

The captcha form field type provides the use of a captcha plugin. Captcha is used on front-end forms to prevent unwanted submission of forms.

This is step-by-step actionable guide on how to create a Joomla Model-View-Controller (MVC) component from scratch.

Form fields are fields in a HTML <form>. In Joomla, you can use JForm class to conveniently and flexibly create forms with a large amount of form fields. These form fields are stored in XML file.

Joomla template framework is a base skeleton template you can use to build more powerful Joomla templates. It means a clean, blank HTML/CSS skeleton with no colors, gradients, borders. You will just get get dimensions, margins, menu system styling.

Articles are assigned to categories, and menu link items are used to open the category or article, which displays in the content area of the website. Most websites have specific articles to be displayed on the front page, and these articles may be assigned to one, or different categories.

When a menu link item is created in any menu, the first action is to select a menu item type. Every website must have at least one menu. Joomla! websites can have many menus, and these can be set to display or not.

The majority of the content on a Joomla! website consists of articles. Articles are assigned to categories, regardless of its hierarchy or level. Subcategories (child categories) can be created and associated with any Category above (a parent category). There is no limit to the number of categories or subcategories that can be created.

The first question asked when a template is installed is, "Where are the module positions and what are they called?" You can easily determine the module positions of any installed Joomla template, whether being used or not.

Joomla! comes with many installed modules. A Joomla! installation can have a number of modules that are installed but have not been included as functional content elements. This means that a module extension can be installed by the Extensions Manager, but not yet included to be part of a web page.

Joomla! was not created from the ground up. It was derived from another program called Mambo, using the open source software forking method, which enables you to use the source code and build on it with your own code.

If you have set up a web hosting account, installing Joomla includes four tasks.

The filelist form field provides a drop down list of files from a specified directory. If the field has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

The category form field type provides a drop down list of all published categories for a certain extension. If the parameter has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

The email form field type provides a text box for entry of an email address. If the field has a value saved, this value is displayed when the page is first loaded. If not, the default value (if any) is selected.

The editor field type provides a WYSIWYG (What You See Is What You Get) editor. You can change the editor configuration and access level display options at the back-end in the plugins section.

Custom fields in Joomla is introduced from 3.7 version. These can be added in your articles, contact forms and user profiles. Through custom fields, you have a seamlessly integrated way to show them on the front end.

The JTable class is used in Joomla for creating, reading, updating, and deleting (CRUD) tasks for records in the database table. JTable provides many methods to make common manipulations to the table much simpler.

You can a submenu using a helper file. The file is stored in helpers folder with the same name as the name of component name (without com_), or else submenus won't show in category view.

This module shows an iframe window to specified location.

he Who's Online Module displays the number of Anonymous Users (e.g. Guests) and Registered Users (ones logged-in) that are currently accessing the website.

This module displays the latest registered users.

If you like to change the way a Joomla! Extension is displayed on your site, you can either re-code the extension from the scratch or you can use overrides. The standard output from any Joomla module or component can be overridden by adding code to the html directory of your template.

This field is like a text field with the type of url.

The checkbox form field type provides a single checkbox. If the parameter has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

It provides a list of available cache handling options.

The checkboxes form field type provides a set of checkboxes. Unlike most standard form field types, such as textfield or checkbox, this field is little different. It will create checkboxes, and submit their values in form of an array, but it will not store them in the database.

It provides a drop down list of style options with the current option selected.

It provides a color picker. Enter the color as #ff00ff or pick it from the palet.

It provides a list of content languages.

It provides an input field for files. When using the file input type, you should always add the attribute enctype="multipart/form-data" to your form tag. Otherwise, the uploaded files will not be attached correctly.

The folderlist form field type provides a drop down list of folders from a specified directory. If the field has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

The groupedlist form field type provides a drop down list or a list box of custom-defined entries which has the ability to show grouped data. If the field has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

It provides a drop down list of h1 to h6 as options.

The hidden form field type provides a hidden field for saving a field whose value cannot be altered directly by a user in the Administrator. It can be altered in code or by editing the xml file.

The integer form field type provides a select box with a range of integer values. If the field has a value saved, this value is displayed when the page is first loaded. If not, the default value (if any) is selected.

The imagelist form field type provides a drop down list of image files in a specified directory. Only files with .png, .gif, .jpg, .bmp, .ico extensions are listed. If the field has a saved value, this is selected when the page is first loaded. If not, the default value (if any) is selected.

The media form field type provides modal access to the media manager for the choice of an image. Users with appropriate permissions will be able to upload files. If the user is not authorised to view or add media they will see an error page in the modal popup.

The menu form field type provides a drop down list of the available menus from Joomla site. If the field has a saved value this is selected when the page is first loaded. If not, the default value (if any) is selected.

The Joomla ACL system is divided into two completely separate systems. The ACL for each is set up differently.

With the help of class JForm, you can easily create HTML forms in Joomla. Forms created using JForm consist of form fields, implemented as JFormFields. There is a JFormField for each different field type you can find in a form, such as a text field type and a date field type. There are many standard field types.

Forms are extensively used in Joomla, both in administration and front-end. You can get data after form submission using JInput. It also provides various ways to filter and sanitise your input data.

In the back-end, administrators can select an image to be associated with each item. You can also display details of the image on the administrator's list of items. In the front-end, display the image associated with the item and also allow a user to upload an image when creating a new item.

Modals are the pop-up-like windows which appear in several places within Joomla. For example, when as an administrator you create a new menu item, and select a Menu Item Type of Single Article, then when you click to select the article, a pop-up appears displaying the details of the articles available and allowing you to select one.