How to setup Dynamic Data Dropdown control in Orbeon Forms CE?

I am a newcomer in the Orbeon forms and I am trying to use Dynamic Data Dropdown component with Orbeon Forms CE but nothing is displayed.

As an example, I am trying to fetch data from the following web service: http://api.geonames.org/earthquakes?north=44.1&south=-9.9&east=-22.4&west=55.2&username=demo&style=full

In order to use the aforementioned web service, I entered the following values in the provided fields:

"Choices XPath expression": "/geonames/earthquake",
"Label XPath expression": "@src" ,
"Value XPath expression: "@eqid"

Unfortunately, the dropdown component is always empty. Is something wrong with the values at these fields? Although, there is available documentation about this component, I've noticed that there is a broken link regarding the sample web service that is used in this documentation.

Thank you

Solution

I had the same problem. Your XML is like:

    <geonames>
       <earthquake>
          <src>us</src>
          <eqid>c0001xgp</eqid>
          <datetime>2011-03-11 04:46:23</datetime>
          <lat>38.322</lat>
          <lng>142.369</lng>
          <magnitude>8.8</magnitude>
          <depth>24.4</depth>
       </earthquake>
       ...

@src is used in case you hace a XML node like <node src="something"/> but in your case what you need is to access to text between tags.

Try with:

"Choices XPath expression": "/geonames/earthquake",
"Label XPath expression": "src/text()" ,
"Value XPath expression: "eqid/text()"

Hope it helps. Regards