fix for #1257

Author: fehguy

dist/swagger-ui.js

@@ -260,7 +260,11 @@ Handlebars.registerHelper('renderTextParam', function(param) {
         result += ' placeholder=\'Provide multiple values in new lines' + (param.required ? ' (at least one required).' : '.') + '\'>';
         result += defaultValue + '</textarea>';
     } else {
-        result = '<input class=\'parameter\'' + (param.required ? ' class=\'required\'' : '') + ' minlength=\'' + (param.required ? 1 : 0) + '\'';
+        var parameterClass = 'parameter';
+        if(param.required) {
+          parameterClass += ' required';
+        }
+        result = '<input class=\'' + parameterClass + '\' minlength=\'' + (param.required ? 1 : 0) + '\'';
         result += ' name=\'' + param.name +'\' placeholder=\'' + (param.required ? '(required)' : '') + '\'';
         result += ' type=\'' + type + '\' value=\'' + defaultValue + '\'/>';
     }