Databases Reference
In-Depth Information
Condition
: Dynamic Actions allow you to perform different actions based on a condition. The
condition is evaluated in real time against the triggering element each time the event occurs. This
condition is not the same as a standard APEX object condition. If the condition is true or not defined,
then the True action(s) are executed. If the condition is false, the False action(s) are performed.
In the example the condition (previously shown in Figure 7-13) is set to is not null. This means that
each time the triggering element P1_DEPTNO is changed, APEX will evaluate it to see if it is null or not. If
it is null then it will hide the list of employees (false action). If a department is selected, it will show the
list of employees (true action).
A list of conditions is shown in Figure 7-15. All conditions, except for is not null and is null, require
that you enter some additional information in the Value field.
Figure 7-15.
List of conditions
The value required for the first six comparison conditions is a static value. You can reference an item
value but you must use the substitution string
&PX ITEM NAME.
notation. If you use a substitution string it
will use the value of the item when the page is loaded which may not be the same value that is currently
on the page when the condition is evaluated.
The two list conditions compare static comma delimited lists. If referencing a substitution string,
the value of the item at the time the page is loaded will be used.
The last condition, JavaScript expression, allows you to compare values in real time when the
condition is evaluated. All the other conditions are evaluated against the triggering element. If you use a
JavaScript expression, you can compare any set of values. In most cases part of the expression will
include the triggering element.
The JavaScript expression condition type contains several objects. They are
