In TPL:Accessing an item without knowing it's name

In my TPL, I need to iterate through an "or" list of replicants. Since it's an "or", each iteration will, presumeably, be a different type of replicant item. How can I determine, as I'm iterating through, what type of replicant I'm dealing with?

The DCT snippet is conceptually like this:

<item name="the_replicant_in_question">
<replicant combination="or">
<item name="item_type_1" />
<item name="item_type_2" />
</replicant>
</item>

As I'm iterating, I need to find out if the current replicant item is an "item_type_1" or an "item_type_2" so I can deal with it properly (in my actual template, "item_type_1" is actually a container with a bunch of sub-items).

Is there a notation for "first occuring child element of the current replicant iteration"? And if so, is there a way to determine the name/type of said "first occuring child element"?

Thanks,
Marc

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Gerard

I'm struggling with the same issue. Can somebody please give us an example of the corresponding Presentation Template logic??

I've tried to use the defined function, something like:

foreach my $replicant_item (iwpt_dcr_list('dcr.the_replicant_in_question'))
{
if (defined iwpt_dcr_value('replicant_item.item_type_1') )
{
}
else #item_type_2
{
}
} #end foreach

But this did not work.

Gerard.

Edited by Gerard on 08/07/02 05:15 AM (server time).

Migrateduser

I wrote some code to do this about six months ago, but I can't find it right now. I can give you the basic overview of what you need to do though -

1)The accessor syntax for iw_value, iw_iterate, etc. is basically like XPath except it is DCR-aware. So, if you need to peek further down than one level you can.

2)The DCRnode module (which should already be in your namespace in a PT), has a type method to determine the type and a get_node method to get the node.

What I don't remember off the top of my head is whether this will work:

<iw_iterate var='a' name='dcr.foo'>
<iw_if expr='($a->get_type eq "foo-sub1")'>
<iw_then>
<![CDATA[
some stuff
]]>
</iw_then>
<iw_else>
<![CDATA[
other stuff
]]>
</iw_else>
</iw_if>
</iw_iterate>

will work directly, or whether you have to do an iw_perl block to get the list of nodes and then iterate over them inside some iw_perl. I think the above PT is basically sound... but you might have to play with it a bit to get it to actually work. If I get a chance I'll try to find my code from when I did this and post it.

Cheers,
Rob Huffstedtler
rob@bagpipe.com

manju166

here is another example
it works for me..............

<iw_iterate list='dcr.Item' var='Item'>
<iw_if expr="{iw_value name='Item.Header Url'/} ne ''">
<iw_then>
<![CDATA[<a href="<iw_value name='Item.Header Url'/>"><iw_value name='Item.Header Name'/></a>]]>
</iw_then>
<iw_else>
<![CDATA[<iw_value name='Item.Header Name'/>
</iw_else>
</iw_if>

marcmundt

I found a quick/dirty workaround for this, so I stopped following the thread, but in case the workaround is still useful to anyone, I thought I'd post it.

Here's an example of TPL code. See below for the getChildNode and getNodeType functions.

Basically, I'm cheating by using the current iterant's inner xml:
-Get the inner xml for the current iterant
-Get the type of the first tag contained in the inner xml
-Use the type to get a reference to that first child node

<iw_iterate list='dcr.questions' var='replicant'>
<iw_perl>
<![CDATA[
$questionnode = &getChildNode($replicant);
$questionnodetype = &getNodeType($questionnode);
]]>
</iw_perl>

<![CDATA[


{iw_value name="questionnode.some_field_to_output"/}


]]>
</iw_iterate>

And here are the getChildNode and getNodeType functions:

sub getChildNode {
my $nodereference = $_[0];
my $nodexml = $nodereference->get_inner_xml();
$nodexml =~ m|^<([^>]*)>|;
my $nodetype = $1;
my $childnode = $nodereference->get_node($nodetype);
return $childnode;
}

sub getNodeType {
my $nodereference = $_[0];
my $nodetype = $nodereference->type();
return $nodetype;
}