dart: ">=2.2.0 <3.0.0"

example/lib/main.dart

@@ -40,7 +40,6 @@ class _MyAppState extends State<MyApp> {
 
   @override
   void dispose() {
-    // TODO: implement dispose
     super.dispose();
     _controller.dispose();
   }

pubspec.lock

@@ -7,7 +7,7 @@ packages:
       name: async
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "2.0.8"
+    version: "2.1.0"
   boolean_selector:
     dependency: transitive
     description:
@@ -45,7 +45,7 @@ packages:
       name: matcher
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "0.12.3+1"
+    version: "0.12.5"
   meta:
     dependency: transitive
     description:
@@ -66,14 +66,14 @@ packages:
       name: pedantic
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "1.4.0"
+    version: "1.5.0"
   quiver:
     dependency: transitive
     description:
       name: quiver
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "2.0.1"
+    version: "2.0.2"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -85,7 +85,7 @@ packages:
       name: source_span
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "1.5.4"
+    version: "1.5.5"
   stack_trace:
     dependency: transitive
     description:
@@ -99,7 +99,7 @@ packages:
       name: stream_channel
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "1.6.8"
+    version: "2.0.0"
   string_scanner:
     dependency: transitive
     description:
@@ -120,7 +120,7 @@ packages:
       name: test_api
       url: "https://pub.flutter-io.cn"
     source: hosted
-    version: "0.2.2"
+    version: "0.2.4"
   typed_data:
     dependency: transitive
     description:
@@ -136,4 +136,4 @@ packages:
     source: hosted
     version: "2.0.8"
 sdks:
-  dart: ">=2.1.0 <3.0.0"
+  dart: ">=2.2.0 <3.0.0"