Oracle Magazine - January/February 2011

Database Developer
BROWSER-BASED B Y DAVID PEAKE

Extend Your Applications
Use plug-ins with Oracle Application Express 4.0
to add custom components.
ORACLE APPLICATION EXPRESS 4.0

Oracle Application Express 4.0 intro- duced a plug-in architecture that enables developers to extend their applications with custom item and region types, processes, and dynamic actions. Several plug-ins are free for downloading from Oracle Technology Network, and more than 40 plug-ins developed by members of the Oracle Application Express community are available from an external Website.

This column walks you through building an application that implements and uses three existing plug-ins. You can run through these steps on the hosted instance of Oracle Application Express 4.0 at apex.oracle.com. (You must request a free workspace to use this hosted instance.) You can also use a local instance of Oracle Application Express 4.0. This exercise is based on the EMP table, which is available by default in the database.

appeal to the demonstration application. With the EMP table still open in the Object Browser, follow these steps: Click 1. UI Defaults on the menu.

Click 2. Edit.

Click 3. EMPNO in the table to open the Column Defaults page for the EMPNO column.

Under General Defaults, replace 4. EMPNO in the Label field with Employee Number and then click Apply Changes.

Repeat the preceding step to change the 5. labels for the ENAME, MGR, HIREDATE, SAL, COMM, and DEPTNO columns to, respectively, Employee Name, Manager, Hire Date, Salary, Commission, and Department.

For 4. Page Type, select Report and Form.
Enter EMP for Table Name, click Add Page,
and click Create.

On the summary page, click 5. Create.

Next you’ll install two plug-ins into the Employees application that will help users input data easily into the application’s Phone Number and Rating fields. You’ll also install a plug-in that generates an employee organization chart and adds it to the application’s report page.

MODIF YING THE EMP TABLE

You’ll build a database application that
enables users to view and edit employee data.
Before you create the application, you need to
add two new columns to the EMP table and
change some user interface defaults. Log in to
Oracle Application Express, and follow these
steps to add PHONE_NUMBER and RATING
columns to the EMP table:
From the Oracle Application Express 1.
home page, select SQL Workshop ->
Object Browser.

Select the 2. EMP table from the list.

Click 3. Add Column. Enter PHONE_NUMBER for Add Column, change its Datatype to VARCHAR2, enter 14 for Length, click Next, and click Finish.

Select the 4. EMP table from the list again.

Click 5. Add Column, enter RATING for Add Column, enter 1 for Precision, click Next, and click Finish.

Now you’ll change some of the EMP
table’s column labels to add some visual

CREATING THE DEMONS TRATION
APPLICATION

To create the demonstration application,
follow these steps:
From the Oracle Application Express 1.
home page, select Application Builder.

Click 2. Create. For Application Type, select
Database and From Scratch.

For 3. Name, enter Employees, and then click Next.

DO WNLOADING AND INS TALLING
PLUG-INS

Download the following plug-ins from Oracle Technology Network at oracle.com/ technetwork/developer-tools/apex/ plugins-155231.html, and unzip them to a convenient location on your system:

Masked Text. • This item-type plug-in makes it easy for users to enter fixed-width, formatted data (such as dates, phone numbers, and Social Security numbers).

Star Rating. • This item-type plug-in enables your application’s users to rate something by clicking a star icon representing a rating in any range from 0 to 99, inclusive.