Need to chart attribute value of just one child node of XML document

Question

I have a XML document with (for example) 7 parent nodes, each
parent node has 5 child nodes. The parent nodes have an attribute
@EarlierDTS (DateTime type) that is the x-axis category of a chart.
Each child node has an attribute @eventid which specifies the id of
the event, and another atttribute @NumOccurs which specifies how
many times that event occured in that period.
How do I tell Flex I want a simple line chart of the eventID
= 215? What if I want two lines, for both eventID=215 and
eventid=307?
I have studied the posts and blogs for over a week now, and
have seen this question or similar come up quite a few places, with
no answer.
1) Should I focus on learning how to create a filterfunction
for the XMLList that underlies my XMLListCollection so that the
filtered data view is just one child node per parent node ( or two
child nodes for the second case)? And set the filtered data view as
the dataprovider of my chart's vertical series?
2) Should I focus on learning how to create a XML Filter
query that selects just one or two child nodes for each parent
node, and set the charts' series' dataprovider to this filter
expression? (I don't think this is allowed - but I'm checking with
the forum members...)
3) Should I focus on learning how to convert the
XMLListCollection into a HierarchicalData object, and then learning
how to filter this object so there is only one (or two) childs per
parent? This seems like a lot of coding - I almost have to create a
pair of classes - one for the parent and one for the child - so I
can create nested ArrayObjects.
4) Should I create a brand new XMLList by walking the
original XML list, and inserting Parent nodes and just the child
nodes that match the eventID(s) I want to chart, into the new
XMLList?
I believe that the easiest way would be to create a
Filterfunction for the XMLList, and bind the chart series to the
(filtered) XML List. But the problem with this approach is that I
have seen more than 2 posts asking how to accomplish filtering that
removes specific children from the view, with no solutions posted.
Help! What is the best way to get just one child for each
parent, from an XMLList?

Answer 1

"whertzing" <[email protected]> wrote in
message
news:[email protected]...
>I have a XML document with (for example) 7 parent nodes,
each parent node
>has 5
> child nodes. The parent nodes have an attribute
@EarlierDTS (DateTime
> type)
> that is the x-axis category of a chart. Each child node
has an attribute
> @eventid which specifies the id of the event, and
another atttribute
> @NumOccurs
> which specifies how many times that event occured in
that period.
>
> How do I tell Flex I want a simple line chart of the
eventID = 215? What
> if I
> want two lines, for both eventID=215 and eventid=307?
>
> I have studied the posts and blogs for over a week now,
and have seen this
> question or similar come up quite a few places, with no
answer.
>
> 1) Should I focus on learning how to create a
filterfunction for the
> XMLList
> that underlies my XMLListCollection so that the filtered
data view is just
> one
> child node per parent node ( or two child nodes for the
second case)? And
> set
> the filtered data view as the dataprovider of my chart's
vertical series?
>
> 2) Should I focus on learning how to create a XML Filter
query that
> selects
> just one or two child nodes for each parent node, and
set the charts'
> series'
> dataprovider to this filter expression? (I don't think
this is allowed -
> but
> I'm checking with the forum members...)
>
> 3) Should I focus on learning how to convert the
XMLListCollection into a
> HierarchicalData object, and then learning how to filter
this object so
> there
> is only one (or two) childs per parent? This seems like
a lot of coding -
> I
> almost have to create a pair of classes - one for the
parent and one for
> the
> child - so I can create nested ArrayObjects.
>
> 4) Should I create a brand new XMLList by walking the
original XML list,
> and
> inserting Parent nodes and just the child nodes that
match the eventID(s)
> I
> want to chart, into the new XMLList?
>
> I believe that the easiest way would be to create a
Filterfunction for the
> XMLList, and bind the chart series to the (filtered) XML
List. But the
> problem
> with this approach is that I have seen more than 2 posts
asking how to
> accomplish filtering that removes specific children from
the view, with no
> solutions posted.
>
> Help! What is the best way to get just one child for
each parent, from an
> XMLList?
I'd just look at a dataFunction. There's an example here that
may point you
in the right direction:
http://flexdiary.blogspot.com/2008/08/charting-example.html
HTH;
Amy