Fix Dart 2 type error and deprecation

packages/battery/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.2.1
+
+* Fixed Dart 2 type error.
+* Removed use of deprecated parameter in example.
+
 ## 0.2.0
 
 * **Breaking change**. Set SDK constraints to match the Flutter beta release.

packages/battery/example/lib/main.dart

@@ -62,19 +62,20 @@ class _MyHomePageState extends State<MyHomePage> {
       floatingActionButton: new FloatingActionButton(
         child: const Icon(Icons.battery_unknown),
         onPressed: () async {
+          final int batteryLevel = await _battery.batteryLevel;
           showDialog<Null>(
             context: context,
-            child: new AlertDialog(
-              content: new Text('Battery: ${await _battery.batteryLevel}%'),
-              actions: <Widget>[
-                new FlatButton(
-                  child: const Text('OK'),
-                  onPressed: () {
-                    Navigator.pop(context);
-                  },
-                )
-              ],
-            ),
+            builder: (_) => new AlertDialog(
+                  content: new Text('Battery: $batteryLevel%'),
+                  actions: <Widget>[
+                    new FlatButton(
+                      child: const Text('OK'),
+                      onPressed: () {
+                        Navigator.pop(context);
+                      },
+                    )
+                  ],
+                ),
           );
         },
       ),

packages/battery/lib/battery.dart

@@ -32,8 +32,9 @@ class Battery {
   Stream<BatteryState> _onBatteryStateChanged;
 
   /// Returns the current battery level in percent.
-  Future<int> get batteryLevel =>
-      _methodChannel.invokeMethod('getBatteryLevel');
+  Future<int> get batteryLevel => _methodChannel
+      .invokeMethod('getBatteryLevel')
+      .then<int>((dynamic result) => result);
 
   /// Fires whenever the battery state changes.
   Stream<BatteryState> get onBatteryStateChanged {

packages/battery/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for accessing information about the battery state
   (full, charging, discharging) on Android and iOS.
 author: Flutter Team <flutter-dev@googlegroups.com>
 homepage: https://github.com/flutter/plugins/tree/master/packages/battery
-version: 0.2.0
+version: 0.2.1
 
 flutter:
   plugin:

packages/firebase_messaging/example/lib/main.dart

@@ -94,32 +94,38 @@ class _PushMessagingExampleState extends State<PushMessagingExample> {
   final TextEditingController _topicController =
       new TextEditingController(text: 'topic');
 
-  Future<Null> _showItemDialog(Map<String, dynamic> message) async {
-    final Item item = _itemForMessage(message);
+  Widget _buildDialog(BuildContext context, Item item) {
+    return new AlertDialog(
+      content: new Text("Item ${item.itemId} has been updated"),
+      actions: <Widget>[
+        new FlatButton(
+          child: const Text('CLOSE'),
+          onPressed: () {
+            Navigator.pop(context, false);
+          },
+        ),
+        new FlatButton(
+          child: const Text('SHOW'),
+          onPressed: () {
+            Navigator.pop(context, true);
+          },
+        ),
+      ],
+    );
+  }
+
+  void _showItemDialog(Map<String, dynamic> message) {
     showDialog<bool>(
-        context: context,
-        child: new AlertDialog(
-          content: new Text("Item ${item.itemId} has been updated"),
-          actions: <Widget>[
-            new FlatButton(
-                child: const Text('CLOSE'),
-                onPressed: () {
-                  Navigator.pop(context, false);
-                }),
-            new FlatButton(
-                child: const Text('SHOW'),
-                onPressed: () {
-                  Navigator.pop(context, true);
-                }),
-          ],
-        )).then((bool shouldNavigate) {
+      context: context,
+      builder: (_) => _buildDialog(context, _itemForMessage(message)),
+    ).then((bool shouldNavigate) {
       if (shouldNavigate == true) {
         _navigateToItemDetail(message);
       }
     });
   }
 
-  Future<Null> _navigateToItemDetail(Map<String, dynamic> message) async {
+  void _navigateToItemDetail(Map<String, dynamic> message) {
     final Item item = _itemForMessage(message);
     // Clear away dialogs
     Navigator.popUntil(context, (Route<dynamic> route) => route is PageRoute);