[flutter_example_packages] Fix rotate resize

example/lib/pages/home/page.dart

@@ -29,7 +29,7 @@ class _HomePageState extends AppState<HomePage> {
   final ScrollController _controllerListView = ScrollController();
 
   @override
-  void didChangeMetrics() {
+  void onDidChangeMetrics() {
     setState(() {
       _hH = _header.getHeight() ?? 0;
     });
@@ -125,11 +125,11 @@ class _HomePageState extends AppState<HomePage> {
                 child: Container(
                   key: _header,
                   width: double.infinity,
-                  padding: const EdgeInsets.only(
+                  padding: EdgeInsets.only(
                     left: 20,
                     right: 20,
-                    top: 30,
+                    top: media.orientation == Orientation.portrait ? 30 : 10,
-                    bottom: 90,
+                    bottom: media.orientation == Orientation.portrait ? 90 : 70,
                   ),
                   child: Column(
                     mainAxisSize: MainAxisSize.min,
@@ -139,7 +139,10 @@ class _HomePageState extends AppState<HomePage> {
                         l10n.homeWelcomeTitle,
                         color: Colors.white,
                       ),
-                      const SizedBox(height: 40),
+                      SizedBox(
+                        height:
+                            media.orientation == Orientation.portrait ? 40 : 20,
+                      ),
                       TextBodyLarge(
                         l10n.homeWelcomeText(packages.length),
                         color: Colors.white,

example/lib/widgets/base/app_state.dart

@@ -10,25 +10,35 @@ abstract class AppState<T extends StatefulWidget> extends State<T>
   );
 
   void onPostFrameCallback() {}
+  void onDidChangeMetrics() {}
+
+  void _delayedChangeMetrics() {
+    onDidChangeMetrics();
+    Future.delayed(const Duration(milliseconds: 100), () {
+      onDidChangeMetrics();
+    });
+    Future.delayed(const Duration(milliseconds: 200), () {
+      onDidChangeMetrics();
+    });
+    Future.delayed(const Duration(milliseconds: 500), () {
+      onDidChangeMetrics();
+    });
+  }
 
   @override
   void initState() {
     super.initState();
     WidgetsBinding.instance.addObserver(this);
     WidgetsBinding.instance.addPostFrameCallback((_) {
-      didChangeMetrics();
+      _delayedChangeMetrics();
-      Future.delayed(const Duration(milliseconds: 100), () {
-        didChangeMetrics();
-      });
-      Future.delayed(const Duration(milliseconds: 200), () {
-        didChangeMetrics();
-      });
-      Future.delayed(const Duration(milliseconds: 500), () {
-        didChangeMetrics();
-      });
     });
   }
 
+  @override
+  void didChangeMetrics() {
+    _delayedChangeMetrics();
+  }
+
   @override
   void dispose() {
     WidgetsBinding.instance.removeObserver(this);