The DP4 user interface manager provides an interface between the application and the terminal, or workstation. The user interface manager handles all the calls to the keyboard, screen and printers, Using this interface brings a number of benefits:
The DP4 user interface manager promotes a consistent way of displaying information and has conveneient functions for entering and checking data to be added to the database. The keystrokes to select an item, move around the screen, and exit the current screen are always the same in programs designed using DP4 making it easy to learn how to use new programs, or a new version of a system that has been ported to a different operating system.
DP4 has a user interface which is logically independent of the operating system, so that your application can run both on Microsoft Windows, and other GUI environments, and in text based environments. An application designed for a text based environment subsequently ported to a GUI will automatically support the use of a mouse to select controls, and elements such as Icons, and buttons can be added to the application maps without the need for alterations to program code.
A program written using the DP4 user interface can automatically be run using the DP4 Thin Clinent configuration.
DP4 helps you to design programs for users with different levels of experience:
All users: For a screen containing many fields, the user can short-cut to the next screen, and accept default values for the remaining fields.
Well-written DP4 programs do not contain "locale" sensitive data (such as message text), so it is easy to translate the system to work in another language. It is even easy to run a single installation in several languages at once.
More information on the user interface is contained in the following topics: