Hello eat-sleep-code,
1) Please check out the demo Customized Editors. Notice how the column “Ship Country” has a custom source (an array) for its dropdownlist editor. Instead of the array, you may populate the editor with a data adapter instance in a similar manner you populate the grid itself.
2) To add an empty row, just call:
$('#jqxGrid').jqxGrid('addrow', null, {});
To delete a row, invoke the deleterow method. You can learn more about these functionalities in the jqxGrid API Documentation.
Best Regards,
Dimitar
jQWidgets team
http://www.jqwidgets.com/