Binding Datagrid XML Data

Question

Hi,
Summary: I cannot get my DataGrid binding with XML data.
Specifically, I cannot bind a DataGridColumn with a child of a
child using the dataField property. However, I can bind with a
direct child.
I'm currently building an application where I retrieve data
from a XML database and contact it through posting a XQuery to the
database. I set the resultFormat of my HTTPServer to "e4x".
quote:
<mx:HTTPService id="searchRequest" url="
http://localhost:8080/exist/rest/db/"
contentType="application/xml" useProxy="false"
method="POST" resultFormat="e4x" />
I receive this data:
quote:
<exist:result exist:hits="1" exist:start="1"
exist:count="1" xmlns:exist="
http://exist.sourceforge.net/NS/exist">
<schedule>
<tournament>
<sport>Testing Our DTD</sport>
<tname>Well-formed Document</tname>
<match>
<mdate>Oct. 12, 2007</mdate>
<competitor>
<cname>sd</cname>
<score>2</score>
</competitor>
<competitor>
<cname>sdgs</cname>
<score>3</score>
</competitor>
<location>
<city>San Luis Obispo</city>
<state>CA</state>
<country>USA</country>
<stadium>Test Stadium, OPTIONAL</stadium>
</location>
<tv>SVN</tv>
<description>Basic testing...</description>
</match>
</tournament>
</schedule>
</exist:result>
I receive the data fine however, I cannot nested
elements of the XML nodes I retrieve. Here is my data grid.
quote:
<mx:DataGrid id="grid" width="446" height="100%"
dataProvider="{searchRequest.lastResult.schedule.tournament.match}"
enabled="true">
<mx:columns>
<mx:DataGridColumn headerText="Tournament" />
<mx:DataGridColumn headerText="Match Date"
dataField="mdate" />
<mx:DataGridColumn headerText="Sport" />
<mx:DataGridColumn headerText="City"
dataField="location.city"/>
<mx:DataGridColumn headerText="State"
dataField="location.state"/>
</mx:columns>
</mx:DataGrid>
The 'mdate' shows up however, 'location.city'
and 'location.state' do not. I am not sure how the dataField works.
Does it get the 'current' node and allow me to drill down in the
XML node?
I will note that I can get it working with a labelFunction
and an ItemRenderer. I feel that using either of those methods for
this is a bit verbose.

Answer 1

The default DGColumn picks up the property value by doing
data[dataField]. Due to this the nested value would not be picked
up.
By extending DGColumn and overriding the itemToLabel function
it is possible to get the desired functionality by adding code to
detect "field1.field2" kind of dataField value and returning the
nested value.
This custom DGColumn can be used whererever the functionality
is desired.