With this module you can define two traditional site navigation methods - the top navbar (e.g. http://ibm.com/ or http://cyranosciences.com/) and the left navbar (e.g. http://vg-8.com/). There are benefits to both methods, so often a site will use a combination (http://amazon.com/).
One of the most impressive looking pull down menu systems appears on the main page of Caltech's Career Development Center, but it is java and can cause Netscape (esp. on Linux) to die. Our system does just about as much as this does for a lot less overhead.
[ns/server/yourservername/acs/pdm] ; Flag to display the administration menu bar MenuOnAdminPagesP=1 ; Flag to display the default menu bar on non-/admin pages MenuOnUserPagesP=0
create table pdm_menus (
menu_id integer primary key,
-- programmer friendly title used to call the menu
menu_key varchar(20) unique not null,
-- is this the menu to show if no pdm_key is passed to ad_pdm?
default_p char(1) default 'f' check (default_p in ('t','f')),
-- orientation of the menu, either "horizontal" or "vertical"
orientation varchar(20) not null check (orientation in ('horizontal','vertical')),
-- distance from the left side of the display area
x_offset integer not null,
-- distance from top of the display area
y_offset integer not null,
-- dimensions of a single menu element
element_height integer not null,
element_width integer not null,
-- css-type style guides for the fonts in the menu
main_menu_font_style varchar(4000),
sub_menu_font_style varchar(4000),
sub_sub_menu_font_style varchar(4000),
-- main menu background images and background colors
main_menu_bg_img_url varchar(200),
main_menu_bg_color varchar(12),
-- hl stands for "highlight" - these are what are shown when
-- someone mouses over the menu
main_menu_hl_img_url varchar(200),
main_menu_hl_color varchar(12),
-- background and color definitions for first level sub menu
sub_menu_bg_img_url varchar(200),
sub_menu_bg_color varchar(12),
sub_menu_hl_img_url varchar(200),
sub_menu_hl_color varchar(12),
-- background and color definitions for second level sub menu
sub_sub_menu_bg_img_url varchar(200),
sub_sub_menu_bg_color varchar(12),
sub_sub_menu_hl_img_url varchar(200),
sub_sub_menu_hl_color varchar(12)
);
create table pdm_menu_items (
item_id integer primary key,
menu_id references pdm_menus,
-- within one level, sort_key defines the order of the items
sort_key varchar(50) not null,
-- text of the item to be displayed if no images are shown and
-- as alt text to the images
label varchar(200) not null,
-- url may be null if this item is only used to store other items
url varchar(500),
-- don't show certain elements to people who haven't registered
requires_registration_p char(1) default 'f' check (requires_registration_p in ('t','f'))
);
Netscape does not correctly place form elements on layers. THe best way to deal with this problem is to try to place the pull-down in a place where it won't interact much with forms. For instance, the menu bar could be at the top of a header image and only ever overlay the header.
If a top-level menu item has no children, a javascript error will occur on mouse-over.