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Standard Layout Library
The Standard Layout Library (stdlay.hei)
provides a general framework for the construction of Web Pages
that maintain a consistent "look and feel". Indeed, many of the Component Libraries,
particularly the Outline Library, require the services provided by Standard Layout
in order to work.
You might want to think of the Standard Library as a template-driven approach to
Web Page design. Here is a simple example of how that would work:
<include stdlay.hei>
<stdpage title="My first heitml Page">
This is my first heitml Page
</stdpage>
The stdpage Environment Tag generates all of the
neccessary HTML, TITLE, HEAD, and BODY Tags which are a part of every page. You can see
from the above example how stdpage assigns a title
to a page. As you read further, you will discover how stdpage
allows you to specify other options associated with the HEAD and BODY Tags.
Standard Layout serves as a nice abbreviation to the otherwise cumbersome chore of
inserting the above named Tags into the beginning and end of your pages. But Standard
Layout has many more advantages:
- You can define your own custom page layout and use it in all your pages. Graphics,
Logos, copyright messages, and anything else you desire can all be incorporated into
a single layout definition. This creates a consistent looking Web Site, saves a lot of
typing, and drastically reduces maintenance overhead when you want to make changes.
When your Web Pages are based on a layout, all you need do is change the layout definition,
and every page that uses it will automatically the changes the next time it is called.
- If you've ever been confronted with the frames/no-frames controversy, you'll
be pleased to note that you no longer have to maintain two different versions of
your Web Site. A Standard Layout can be designed to display your pages either way,
drastically reducing your workload.
- Pages using the Standard Layout can be included as a part of another page.
- The Standard Layout provides a compact and simple way to retain the current state
of variables from one page to another.
- The Standard Layout smoothly integrates with Session Mode.
Using Custom Layouts
To create your own layout, first create an include file named
mylay.hei and put it
in a directory within the include path.
For example:
<include stdlay.hei>
<defenv stdFooting> / / Define page foot here
<p>
<© by me
</defenv>
/ /
/ / Set colors here
<stdParam bgcolor="ffffff" link="ff0000"
alink="ff0000" vlink="c00000">
As declared above, stdFooting defines a footer for
each Web Page, in this case a copyright message. The
stdParam Tag defines the color scheme to be
used.
To use these Tags in your pages, just include
mylay.hei instead of
stdlay.hei into your pages.
Your pages will then use this formatting (i.e. the defined colors) and
the copyright message will appear as a footer (i.e. the last thing that
appears at the bottom of each page).
All the Tags you can use to customize the layout are described in
detail below. They can be used within your page layout (e.g. mylay.hei) to apply for
all pages using this layout, or they can be used within a single page to
modify the layout for just one page.
Formatting Tags
< stdpage title > ...
</stdpage>
Creates a page using the standard layout. The title must be a string specifying
the document title.
< stdHeading >
Redefine this Tag to create a heading on all of your pages.
Anything you define here is placed into the page just after the HTML <body>
Tag, but before the normal text.
< stdFooting >
Redefine this Tag to create a page footer on all of your pages. Anything you
define here is placed into the page just before the HTML </body> Tag, but after the
normal text. If you want a copyright message to appear at the bottom of all your pages,
this is where you would put it.
< stdParam background=null bgcolor="ffffff" text=null
link=null alink=null vlink=null >
This Tag allows you to specify a background picture and color scheme for your pages.
Background is the name of a background picture; bgcolor, text, link, alink, and
vlink are the colors as used in the HTML <body> Tag.
The stdParam Tag must be used before the
stdPage Tag. It can be used either in
the custom layout include file or in the page itself. Subsequent calls to
stdParam overwrite the values set by earlier calls,
so the parameters set in the layout file can be re-defined within the page itself.
< stdNormalPage > ...
</stdNormalPage>
Redefining this Tag is an alternative to redefining the
stdHeading and
stdFooting Tags. It is more powerful but also a
bit more difficult to use. This Environment Tag defines the whole page body. The
environment is called with the page body as the environment parameter.
Including Pages
Standard Layout pages can be included as the part of another page. For
example, you can paste many pages together to create a single large document. This is
particularly useful to obtain a print out of all pages within a related document,
application, or Web Site. All you need do is write:
<include PageToInclude.hei>
somewhere in a page. Note: This works only if both pages are using the
standard layout.
If a page is included, no HTML, BODY, HEAD, and TITLE Tags are
generated. You can also define other Headings and Footings using
the following Tags:
< stdIncHeading >
< stdIncFooting >
< stdIncPage > ...
</stdIncPage>
These Tags work as their counterparts without the Frame in the name
(stdHeading, stdFooting and stdNormalPage) but they are used if the page is
called inside a frame.
By default, no headings and footings are displayed on included pages.
Session Mode
The stdlay.hei
works well with Session Mode. You can simply
include session.hei
and use the session Environment Tag around the
stdpage Environment Tag.
If you have not included session.hei
you naturally can not access the session variables but you can still use the
sa , sessionHidden
, and sessionUrl tags. (See the Language Reference for a
description of these Tags.) Using them keeps the
Uuser within a single session (i.e. if the User klicks on another link pointing to a
page with Session Mode, the old session continues).
Limited Session Mode
Pages using Standard Layout can also use Session Mode in
a limited manner to handle Session Variables. This Limited Session Mode is
weaker than normal Session Mode because it handles String Variables only. Data
is sent to the client and back again (which causes net traffic) with each page call.
However, this method may have some performance advantages over the full-blown
Session Mode, and, since it does not automatically switch
off proxies, can be useful in special situations.
The Limited Session Variables are named
ff.s.variablename, where
variablename
is the name of the variable whose value you wish to preserve between pages.
You can assign a string type value to such a
variable. This value will then be passed through the URL to the next page.
Internally the variables are passed within the URL (i.e. the
sa Tag appends
the to the URL and the
sessionHidden Tag generates hidden fields
to pass the parameters).
In order to work properly the sa , sessionHidden
, and sessionUrl Tags must be used to link pages.
(See the language reference for a description of these
Tags.)
Frame Mode
Normally pages have a different basic layout depending on wether they are used
alone or within a frame. With the Standard Layout Libraries you can
design pages that are used in a "stand alone" fashion in some parts of your
Web Site, and within a frame in other parts.
< stdFrameHeading >
< stdFrameFooting >
< stdFramePage > ...
</stdFramePage>
These Tags work as their counterparts without the Frame in the name
(stdHeading, stdFooting and stdNormalPage) but they are used if the page is
called inside a frame.
Standard Layout knows from a form parameter called
ff.s.inframe whether the page is
called inside a frame. The User is responsible for setting this parameter. But
notice that this is a variable of the Limited Session Mode type, so it is passed on
from page to page.
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