Paging in the SAPgui
You need to assign a separate subscreen area to each tab title, and define the function codes of the tab titles with type P (local GUI function). In the screen flow logic, you call all the subscreens in the PBO event. This means that all of the tab pages reside locally on the SAPgui.
When the user chooses a tab title, paging takes place within the SAPgui. In this respect, the tabstrip control behaves like a single screen. In particular, the PAI event is not triggered when the user chooses a tab title, and no data is transported. While this improves the performance of your tabstrip control, it also has the negative effect that when the user does trigger the PAI event, all of the input checks for all of the subscreens are performed. This means that when the user is working on one tab page, the input checks may jump to an unfilled mandatory field on another page.
Local paging at the SAPgui is therefore most appropriate for screens that display data rather than for input screens.
Paging on the Application Server
One subscreen area is shared by all tab titles and called in the PBO event. You define the function codes of the individual tab titles without a special function type. When the user chooses a tab page, the PAI event is triggered, and you must include a module in your flow logic that activates the appropriate tab page and assigns the correct subscreen to the subscreen area.
Since the PAI event is triggered each time the user chooses a tab title, this method is less economical for the application server, but the input checks that are performed only affect the current tab page.
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Does anyone know the exact location of the sap page file in the OS?
rdisp/rpag_file, usually something like