The StateModified event fires when fields are filled in, and the ModifyState event can be used to update filled-in field values. The example below demonstrates using a StateModified event handler to get the filled-in values of two fields and fire the ModifyState event to fill in a third field with the sum:
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                    viewer.eventStore.on('StateModified', function (ev, data) { if (data.state === 'FieldList') { var value1 = parseInt(data.stateValue.fieldList[1].value); var value2 = parseInt(data.stateValue.fieldList[2].value); data.stateValue.fieldList[3].value = (value1 + value2).toString(); viewer.eventStore.trigger('ModifyState', { state: 'FieldList', stateValue: data.stateValue }); } });  | 
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