Gravity Forms – Make a datepicker’s availability dependant on a different datepicker field

Javascript:
gform.addFilter( ‘gform_datepicker_options_pre_init’, function( optionsObj, formId, fieldId ) {
if ( formId == 1 && fieldId == 1 ) {
optionsObj.minDate = 0;
optionsObj.onClose = function (dateText, inst) {
jQuery(‘#input_1_2’).datepicker(‘option’, ‘minDate’, dateText).datepicker(‘setDate’, dateText);
};
}
return optionsObj;
});