A.1.1 About Oracle Forms Components

You can store an alert message as a text message in Shared Components in an Oracle Application Express application. You can use text messages to build translatable text strings with substitution variables that can be called from PL/SQL packages, procedures, and functions.

A single block correlates to a region in Oracle Application Express. The corresponding region type in Oracle Application Express depends upon the block type and data source type (that is, table or view) specified in Oracle Forms. For example, a report block based on an Oracle view, correlates to an interactive report in Oracle Application Express. A form block based upon a table correlates to an interactive report and form in Oracle Application Express.

In Oracle Forms, the canvas is the object on which the graphical user interface (GUI) is drawn, or the background of the form. In Oracle Application Express, the Application Express engine constructs the appearance of each page in an application using templates. Templates define how pages, page controls, and page components display.

Depending on the coordinate system used in an Oracle Forms application, coordinates can be expressed in real units such as inches, centimeters, and pixels. The Universal Theme within Application Express is a fully responsive theme, which adjusts based on the screen size. For tablets and smartphones the size of the screen is significantly smaller than for desktops, so the page will be rendered responsively by changing the size and positioning of regions and even moving labels above items instead of to the left. As such, Application Express does not support coordinate positioning, or pixel perfect layout, of regions or items on a page as there is with Oracle Forms. Application Express uses a grid layout to set out elements and attributes (such as New Line, New Field, Column Span, and Row Span) to determine how elements are located.

In Oracle Forms, editors provide standard editing features, including search and replace and cut, copy, and paste for text items. Within Oracle Application Express you can define a field as type Rich Text Editor.

A list of values (LOV) can be mapped to an equivalent list of values in Oracle Application Express. When defining a list of values in Oracle Application Express, use the Oracle Forms record group as a reference.

Program units can be incorporated into your Oracle Application Express application as a PL/SQL package, page process, computation or validation.

In Oracle Forms, a property class is a named object that contains a list of properties and their settings. An object based on a property class can inherit the settings of any property in that class. Similarly, in Oracle Application Express, a theme is a named collection of templates used to define the user interface of an application.

In Oracle Forms, LOV values are derived from a record group. When a record group is defined, it is associated with a SQL query. Utilize the SQL query from the record groups as the basis for SQL queries in corresponding LOVs within Oracle Application Express.

An Oracle Forms trigger is an event-handler written in PL/SQL to augment the default processing behavior. The trigger logic can be incorporated into an Oracle Application Express application as a computation, validation, or PL/SQL process after creating the initial application.

Visual attributes are the font, color, and pattern properties that you can set for form and menu objects that appear in an Oracle Forms application's interface. Using the default cascading style sheets (CSS) installed with Oracle Application Express, or by uploading your own CSS files, style can be applied to your Oracle Application Express application.

A window is the container for all visual objects that comprise an Oracle Forms application, including canvases. A windows corresponds to a page in Oracle Application Express. A page holds all of the visual objects for an application.