From c7da8d411a07a1ce04c84d5cea16848d0fb1decc Mon Sep 17 00:00:00 2001
From: Lelouch99 <37395860+jweiw99@users.noreply.github.com>
Date: Tue, 4 Feb 2020 16:39:48 +0800
Subject: [PATCH] fix issue #16

---
 lib/_src/dropdown_list_menu.dart | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/_src/dropdown_list_menu.dart b/lib/_src/dropdown_list_menu.dart
index d207938..ba94c8a 100644
--- a/lib/_src/dropdown_list_menu.dart
+++ b/lib/_src/dropdown_list_menu.dart
@@ -145,11 +145,11 @@ class DropdownTreeMenu<T, E> extends DropdownWidget {
 
   @override
   DropdownState<DropdownWidget> createState() {
-    return new _TreeMenuList();
+    return new _TreeMenuList<T, E>();
   }
 }
 
-class _TreeMenuList<T, E> extends DropdownState<DropdownTreeMenu> {
+class _TreeMenuList<T, E> extends DropdownState<DropdownTreeMenu<T, E>> {
   int _subSelectedIndex;
   int _selectedIndex;