These steps are applicable to AEM Forms 6.2 release
To populate a drop down list from the results returned by the webservice, your webservice must return xml and that xml must have repeating elements. You can then bind one of the elements inside the repeating elements to your drop down list. To do this perform the following
I used the following web service for this example
http://wsf.cdyne.com/WeatherWS/Weather.asmx?op=GetCityForecastByZIP
AS you can see this web service returns XML which has repeating elements "Forecast" and we will use the "MorningLow" to populate our drop down list
Drag a text field on to the form. Name it "Zip"
Drag dropdown list on to your adaptive form. Name it "Forecast"
Select the field "Forecast" and select the "Hammer Icon" to open the rule editor
Click Create
Click the Form Objects and Functions to bring up the Forms Objects explorer on the left hand side of the screen
In the Rule Editor on the right hand side of the screen you should see a drop down list with a value of "when". Change that value to "Set Options Of"
what you are doing here is essentially setting the options of your drop down list.
Then click on the "Select Option" drop down list and choose Web Service Output
paste "http://wsf.cdyne.com/WeatherWS/Weather.asmx?wsdl" in to the text box and tab out
then in the Select Operation drop down list choose "GetCityForecastByZip"
The selected web service operation requires you to provide an Zip code value
Drag the "Zip" field from the Form Object explorer which is on your left and drop into the text field which says "Drop Object or select here"
Then select the "Save Value" drop down list to choose the value that you want to populate your drop down list . I chose "MorningLow"
Preview the form and provide a valid in the zip code field and tab out
