Session state, again

Question

Hi,
I am still struggling after session state updates.
Here is my problem:
I have a page containing two regions (besides the breadcrumbs):
the first region contains a couple of combo boxes containing "filters" for the chart.
The second region contains a pie chart and the sql expression contains two bind variables referencing the aforementioned filters.
The chart in turn contains links to itself, because the value represented by each slice can be used to split the data into further categories. This is achieved via a hierarchical query representing categories of items, so, for instance, category "Food" is parent of "Beverage" and "Beverage" is parent of "Wines". So when you click on slice "Food", the underlying query returns all the categories belonging to "Food".
Until now I could not figure out a way to handle the browser's back button correctly, because the "recursive" nature of this scenario is messed up by session state, whose values persist beyond the scope of each page.
This situation leads to strange results, where the form fields show the correct data, whilst the chart is drawn on entirely different values. This happens only when navigating backwards or forwards using the browser's back or forward button.
Is there any way to force form values to take precedence over session state values, eventually via javascript, so that the back button returns a meaningful page?
I tried with different approaches but with little success, so I was wondering if you have any known workaround.
Thanks,
Flavio

Answer 1

Hi Francis,
We have used the following code in our page template and it works.
<script>
//Disables the browser back button
javascript:window.history.forward(1);
</script>
And in the "Error Page Template Control" to
<TABLE >
<TR>
<TD valign="TOP"><IMG SRC="&IMAGE_PREFIX.error.gif" width=32 height=32></TD>
<TD valign="CENTER"><font size=+1>#MESSAGE#</font></TD>
</TR>
<TR><TD><A HREF="f?p=&FLOW_ID.:&FLOW_STEP_ID.:&SESSION.::&DEBUG."><IMG SRC="&IMAGE_PREFIX.back.gif" title="Back" alt="Back to previous page" width=32 height=32 border=0></A></TD>
<TD>Back</TD>
</TR>
</TABLE>
<table>
<tr><TD><A HREF="f?p=100:1:&SESSION.::&DEBUG." Title="Click here to go back to Main Menu">Go back Home</A></TD></tr>
</table>
You need to change or add error template because the default functionality of "javascript:window.history.go(-1)" will not work
Hope this helps
Vivek