User interface — Concepts and terms In Pega 7

Based on HTML and XML standards, PRPC can support a wide range of user interaction facilities and approaches. Your application's user interface can take into account the environment, the domain knowledge of your users, their skills, locale, and language.
The appearance, branding, and interaction dynamics of your user interface can match the context and language that is natural to your application's users.
Evolving an application's user interface is best done by designers and developers who have both application domain knowledge and usability skills.
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Producing HTML displays and forms

PRPC includes standard facilities for those workers and managers who use PRPC-based applications throughout the workday. These facilities support:

• Entry of new cases
• System-maintained worklists of assignments sorted by decreasing urgency
• Finding, reviewing, updating, and performing assignments

Sophisticated and powerful standard forms known as harnesses are designed for reuse and customization.

Defining user input forms and displays

​For access through the standard portal, PRPC uses harnesses (Rule-HTML-Harness rule type) for work items. Six other rules support the presentation of work items:

• Sections define the contents, appearance, and behavior of portions of harness forms.
• Fragments contain reusable HTML text elements not dependent on a class.
• Control rules determine the appearance of a single property on an HTML input form or display.
• Text File rules, which can define static aspects of your user interface such as Cascading Style Sheets or JavaScripts.
• Binary File rules, which identify images such as JPG or GIF files.

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The HTML text you enter into HTML rules is known as source HTML. It contains ordinary HTML code plus JSP tags or directives — server-side instructions that PRPC evaluates at runtime to compose the final HTML it sends to the HTTP server (and ultimately to a user's browser session). Known as stream processing, this evaluation accesses the clipboard for text values to insert into the output HTML, incorporates the text of other HTML rules, provides conditional if-then-else testing, and looping through arrays.

Harness forms use the pega:include JSP tag to incorporate multiple sections, which in turn use standard styles and fragments to present properties, labels, and images. For your application, you can copy and tailor parts of these forms as necessary, while inheriting the standard parts.

Tools
​These tools support your evolution of the user interface of your applications:

• Harnesses preview and the Application Explorer — Allow you to interactively revise the content and the layout of a user form or flow action form
• UI Gallery — Presents working examples of controls and user interface features
• UI Inspector — View UI structure for elements in your development environment or application
• UI Tree — View and interact with the hierarchy of page artifacts in a developer environment or in an application at runtime
• Image Library landing page tab — Helps you find and identify the name of images that are available as binary file references
• Clipboard tool — Shows the current property values in internal format

Through open authoring, you can use an HTML editor of your choice to revise HTML text.
When a user submits an HTML form, PRPC records the values entered into input fields as property values on the clipboard. The values that users enter may not be in the format required by the property definition, or may not pass validation tests.