Architecture - Expert Oracle Application Express - page 514

Figure 12-4 . Application Builder page branch
Most branches are implemented as redirects; however, you can create branches that simply call the
“page show” method directly.
Session State Management
When a user runs an application, regardless of whether it is an authenticated or unauthenticated
application, they are assigned a random but unique session ID. This session ID is maintained on “page
gets” by passing the numeric session identifier in the third position on the f?p syntax:
f?p=<application>:<page>:<session ID>
“Page posts” pass the session ID as a hidden form element. The session ID maintains the user's
context in the application and allows the user to have access to session state set on previous page views.
Session state is automatically maintained for page items—developers need not write any code to
save session state. An example of a page item is displayed in Figure 12-5. The name of the page item in
the application is P1 SEARCH , and it is displayed as a large input text field. When the page is posted, the
text entered is set as session state for the item P1 SEARCH within the user's session.
Figure 12-5 . Example page with page item P1_SEARCH
All page items and application items must be uniquely named within an application. All session
state is global, meaning that session state values can be accessed from any page or application
component. Session state can also be set using the f?p syntax —see Listing 12-3 below which includes
the full f?p syntax.