Databases Reference
In-Depth Information
Figure 2-34.
Flash procedure in the apex_util (htmldb_util) package
When calling the AnyChart objects, AnyChart might append various parameters to the XML file.
These parameters are there to influence the behavior of the Flash objects. For example,
XMLCallDate
is
used to make sure every call is unique and the browser is not caching the result.
APEX_UTIL
is actually a
synonym for the
HTMLDB_UTIL
package. The flash procedure in the
apex_util
package can accept all these
parameters. There is one important parameter called
p
, which is the URL the AnyChart object has to call
back to get the data. The URL in the
p
parameter includes the application, page, and region so Oracle
APEX knows which data (XML) it needs to generate for that specific chart.
More graphically presented, the flow is like that shown in Figure 2-35.
Figure 2-35.
Graphical representation of the flow to generate the chart
The following is an explanation of the steps shown in Figure 2-35:
1.
User requests a page with a chart, so the browser sends a request to APEX to
retrieve the page.
2.
APEX handles the request and sends back the HTML for that page which
includes the tag to include the Flash file.
3.
The browser shows the HTML page and renders the Flash object which will do
a request back to APEX to get the data for the chart.
4.
APEX retrieves the request and sends back the XML for the data of the chart.
Looking at a real case when a user requests a page that holds a chart:
5.
User clicks on tab which does a call with this url:
http://webserver/pls/apex/f?p=40:15:2887089650234857:::::
.
