diff --git a/examples/stocks2/lib/stock_app.dart b/examples/stocks2/lib/stock_app.dart
index 0b07d84f872..8dd1fda6b9c 100644
--- a/examples/stocks2/lib/stock_app.dart
+++ b/examples/stocks2/lib/stock_app.dart
@@ -158,7 +158,7 @@ class StocksApp extends App {
     return new ToolBar(
         left: new IconButton(
           icon: 'navigation/menu_white',
-          onGestureTap: _drawerController.toggle),
+          onGestureTap: (_) => _drawerController.toggle()),
         center: new Text('Stocks'),
         right: [
           new IconButton(