1 files changed, 11 insertions, 4 deletions
diff --git a/src/widgets.js b/src/widgets.js
index 43bed81f..5df92de0 100644
--- a/src/widgets.js
+++ b/src/widgets.js
@@ -35,16 +35,23 @@ function compileValidator(expr) {
 function valueAccessor(scope, element) {
   var validatorName = element.attr('ng-validate') || NOOP,
       validator = compileValidator(validatorName),
-      required = element.attr('ng-required'),
+      requiredExpr = element.attr('ng-required'),
       farmatterName = element.attr('ng-format') || NOOP,
       formatter = angularFormatter(farmatterName),
-      format, parse, lastError;
+      format, parse, lastError, required;
       invalidWidgets = scope.$invalidWidgets || {markValid:noop, markInvalid:noop};
   if (!validator) throw "Validator named '" + validatorName + "' not found.";
   if (!formatter) throw "Formatter named '" + farmatterName + "' not found.";
   format = formatter.format;
   parse = formatter.parse;
-  required = required || required === '';
+  if (requiredExpr) {
+    scope.$watch(requiredExpr, function(newValue) {
+      required = newValue;
+      validate();
+    });
+  } else {
+    required = requiredExpr === '';
+  }
 
   element.data('$validate', validate);
   return {
@@ -80,7 +87,7 @@ function valueAccessor(scope, element) {
           validateScope = extend(new (extend(function(){}, {prototype:scope}))(), {$element:element});
       error = required && !value ?
             "Required" :
-            (value ? validator({state:validateScope, scope:{get:validateScope.$get, set:validateScope.$set}}, value) : null);
+            (value ? validator(validateScope, value) : null);
       elementError(element, NG_VALIDATION_ERROR, error);
       lastError = error;
       if (error) {