SECTION 8.3
603
Page-Level Navigation
2. The node specified by
Next
(if present) becomes the new current navigation
node.
Similarly, if there is a request to navigate backward and there is a current naviga-
tion node, the following occurs:
1. The sequence of actions specified by
PA
(if present) is executed.
Note:
If
PA
specifies an action that navigates to another page, the actions de-
scribed below for navigating to another page take place, and
Prev
should not be
present.
2. The node specified by
Prev
(if present) becomes the new current navigation
node.
When navigating between nodes, it is possible to specify transition effects. These
effects are similar to the page transitions specified in the previous section. How-
ever, they use a different mechanism; see “Transition Actions” on page 670.
Note:
“Forward” and “backward” are determined by user actions, such as pressing
right or left arrow keys, not by the actual page that is the destination of an action.
If there is a request to navigate to another page (regardless of whether there is a
current node) and that page’s dictionary contains a
PresSteps
entry, the following
occurs:
1. The navigation node represented by
PresSteps
becomes the current node.
2. If the navigation request was forward, or if the navigation request was for ran-
dom access (such as by clicking on a link), the actions specified by
NA
are exe-
cuted and the node specified by
Next
becomes the new current node, as
described above.
If the navigation request was backward, the actions specified by
PA
are execut-
ed and the node specified by
Prev
becomes the new current node, as described
above.
3. The viewer application makes the new page the current page and displays it.
Any page transitions specified by the
Trans
entry of the page dictionary are
performed.