Kbase 15567: Frequently Asked Questions about Paging Applications ( V8 )
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/16/2008 |
|
Status: Verified
GOAL:
Several common questions FAQ from Application Developers regarding the design of paging applications.
There are some restrictions to be aware of concerning the design of paging applications. These should be taken into account before beginning an implementation.
FACT(s) (Environment):
Progress 8.x
Progress ADM
FIX:
-- What is a Paging Application?
A paging application is one which allows the user to access logical
objects grouped by the Developer into separate visual sets. One
common implementation is seen with "Tab Folders" -- a graphic
representation of a Rolodex or tabbed file folders which can be
individually accessed by clicking on the desired "tab". As each page
is brought into view, others are hidden. The entire set of pages
resides in a single window. The paging mechanism could alternatively
be visualized as a radio-set, a row of buttons, or other objects.
-- Can a basic window support a paging application?
No. You must use a SmartContainer in order to implement paging.
One of the functions built into SmartContainers is page management.
You can add paging to any SmartContainer (SmartWindow, SmartFrame,
or SmartDialog).
-- How many pages can I have?
As many as you'd like and your application can support.
-- Can I skip page number?
Yes. Page numbers need not be used sequentially.
-- What is page 0 used for?
Page 0 should be used only for those objects which will remain in
view at all times, regardless of the page selected by the user.
It can be thought of as a background for the remaining pages. If you
use basic objects in your paging application, they will fall through
to Page 0 unless you build an intermediate SmartObject to contain
them, or hide and view them in the local-change-page procedure
(see related KBase 15420 "Basic Widgets Can Only be on Page 0 or Use local-change-page").
-- How do I change pages within my application?
Use the select-page method when you want to change pages in your
application. For example:
ON CHOOSE OF order-info-button DO:
RUN select-page(2).
END.
This example will hide whatever page is currently displayed (except
for page 0) and then view the contents of page 2.
-- How to I change the design page in the UIB?
You can either double-click the current page field in the UIB Status
Bar (below the ToolBar and object title) or you can pull up the
Procedure Settings for the container and click on the Pages icon,
then press the Design button.
-- Can I have two paging visualizations in a container?
No. Each SmartContainer can have only one graphical paging
visualization such as Tab Folders, Rolodex or Notebooks. If your
application requires multiple paging visualizations, you will have
to place each in a separate SmartContainer. These SmartContainers
can, in turn, be placed on separate pages of another SmartContainer.
-- Can I have multiple windows in a paging application?
Yes, you can place any SmartObject on a page, including
SmartContainers. However, you may have to use a pass-through link
to pass certain information to those containers. Pass-through links
are described in the documentation referenced below.