I tried returning false from my function and it didn’t work. This is what worked for me to disable editing in the first column:
$("#jqxgrid").on('cellbeginedit', function (event) { var column = args.datafield; var row = args.rowindex; if( $('#jqxgrid').jqxGrid('getcolumnindex', args.datafield) == "0") { $("#jqxgrid").jqxGrid('endcelledit', row, column, true); } });