diff --git a/src/DependentSelectBox/JsonDependentSelectBox.php b/src/DependentSelectBox/JsonDependentSelectBox.php
index 3e2033e..7c2020e 100644
--- a/src/DependentSelectBox/JsonDependentSelectBox.php
+++ b/src/DependentSelectBox/JsonDependentSelectBox.php
@@ -35,15 +35,19 @@ protected function addJsonResponseItem($selectBox) {
 	public static function tryJsonResponse(Presenter $presenter) {
 		if(empty(self::$jsonResoponseItems))
 			return;
-		
+
 		$payload = array(
 			"type" => "JsonDependentSelectBoxResponse",
 			"items" => array()
 		);
 		foreach(self::$jsonResoponseItems as $item) {
+			$items = $item->getItems();
 			$payload["items"][$item->getHtmlId()] = array(
 				"selected" => $item->getValue(),
-				"items" => $item->getItems()
+				"items" => array(
+					"keys" => array_keys($items),
+					"values" => array_values($items),
+				),
 			);
 		}
 		$response = new JsonResponse($payload);
@@ -65,5 +69,5 @@ public static function Container_prototype_addJsonDependentSelectBox(FormContain
 	public static function register($methodName = "addJsonDependentSelectBox") {
 		FormContainer::extensionMethod($methodName, "DependentSelectBox\JsonDependentSelectBox::Container_prototype_addJsonDependentSelectBox");
 	}
-	
+
 }
diff --git a/src/DependentSelectBox/dependentselectbox.ajax.js b/src/DependentSelectBox/dependentselectbox.ajax.js
index 8ebc701..2e600e6 100644
--- a/src/DependentSelectBox/dependentselectbox.ajax.js
+++ b/src/DependentSelectBox/dependentselectbox.ajax.js
@@ -31,11 +31,12 @@ $.nette.ext('dependentselectbox', {
 	updateSelectBox: function(id, selectedKey, items) {
 		$("#" + id + " option").remove();
 		var select = $("#" + id);
-		for (var i in items) {
-			var item = $("<option></option>").attr("value", i).html(items[i]);
-			if (i === selectedKey)
+		for (var i = 0; i < items.keys.length; i++) {
+			var key = items.keys[i];
+			var item = $("<option></option>").attr("value", key).html(items.values[i]);
+			if (key === selectedKey)
 				item.attr("selected", "selected");
-			if (i === "")
+			if (key === "")
 				select.prepend(item);
 			else
 				select.append(item);
diff --git a/src/DependentSelectBox/jquery.nette.dependentselectbox.js b/src/DependentSelectBox/jquery.nette.dependentselectbox.js
index f49c35f..efbd490 100644
--- a/src/DependentSelectBox/jquery.nette.dependentselectbox.js
+++ b/src/DependentSelectBox/jquery.nette.dependentselectbox.js
@@ -39,14 +39,15 @@ jQuery.extend({
 		updateSelectBox: function(id, selectedKey, items) {
 			$("#" + id + " option").remove();
 			var select = $("#" + id);
-			for(var i in items) {
-				var item = $("<option></option>").attr("value", i).html(items[i]);
-				if(i == selectedKey)
+			for (var i = 0; i < items.keys.length; i++) {
+				var key = items.keys[i];
+				var item = $("<option></option>").attr("value", key).html(items.values[i]);
+				if (key === selectedKey)
 					item.attr("selected", "selected");
-				if(i == "")
-				  select.prepend(item);
+				if (key === "")
+					select.prepend(item);
 				else
-				  select.append(item);
+					select.append(item);
 			}
 		},