None of the existing controls will do that automatically, but the CAF javascript API does have the necessary functionality to do that. See: http://techcommunity.softwareag.com/ecosystem/documentation/webmethods/wmsuites/wmsuite8-2_sp2/My_webMethods/8-2-SP1_CAF_JavaScript_Reference/index.html
You could use a generic ‘Output > Button’ control and write some custom javascript for the ‘Client-Side Events > Click’ control property that uses the CAF javascript APIs to add the row to the table.
For example, the click script would look something like this:
//get the row model object for the clicked row
var rowId = $(this).up('tr').id;
var rowModel = CAF.model(rowId);
//get the table model object
var tableId = $(this).up('table').id;
var tableModel = CAF.model(tableId);
//get the index of the current row
var idx = tableModel.indexOf(rowModel);
//add the row.
// First arg is the index of the new row.
// Second arg is the CAF.Row.Model object to use to populate
// the values for new row.
tableModel.add(idx, rowModel);
#webMethods#MWS-CAF-Task-Engine#webMethods-BPMS