Layout sizing example app

examples/layout/sizing/README.md

@@ -0,0 +1 @@
+../../README.md

examples/layout/sizing/lib/main.dart

@@ -0,0 +1,72 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart' show debugPaintSizeEnabled;
+
+void main() {
+  debugPaintSizeEnabled = true; // Remove to suppress visual layout
+  runApp(MyApp());
+}
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Flutter layout demo',
+      home: Scaffold(
+        appBar: AppBar(
+          title: Text('Flutter layout demo'),
+        ),
+        // Change to buildFoo() for the other examples
+        body: Center(child: buildExpandedImages()),
+      ),
+    );
+  }
+
+  Widget buildOverflowingRow() =>
+      // #docregion overflowing-row
+      Row(
+        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+        children: [
+          Image.asset('images/pic1.jpg'),
+          Image.asset('images/pic2.jpg'),
+          Image.asset('images/pic3.jpg'),
+        ],
+      );
+  // #enddocregion overflowing-row
+
+  Widget buildExpandedImages() =>
+      // #docregion expanded-images
+      Row(
+        crossAxisAlignment: CrossAxisAlignment.center,
+        children: [
+          Expanded(
+            child: Image.asset('images/pic1.jpg'),
+          ),
+          Expanded(
+            child: Image.asset('images/pic2.jpg'),
+          ),
+          Expanded(
+            child: Image.asset('images/pic3.jpg'),
+          ),
+        ],
+      );
+  // #enddocregion expanded-images
+
+  Widget buildExpandedImagesWithFlex() =>
+      // #docregion expanded-images-with-flex
+      Row(
+        crossAxisAlignment: CrossAxisAlignment.center,
+        children: [
+          Expanded(
+            child: Image.asset('images/pic1.jpg'),
+          ),
+          Expanded(
+            flex: 2,
+            child: Image.asset('images/pic2.jpg'),
+          ),
+          Expanded(
+            child: Image.asset('images/pic3.jpg'),
+          ),
+        ],
+      );
+  // #enddocregion expanded-images-with-flex
+}

examples/layout/sizing/pubspec.yaml

@@ -0,0 +1,23 @@
+name: layout
+description: >
+  Sample app from "Building Layouts", https://flutter.io/docs/development/ui/layout.
+version: 1.0.0
+
+environment:
+  sdk: '>=2.0.0-dev.68.0 <3.0.0'
+
+dependencies:
+  flutter:
+    sdk: flutter
+  cupertino_icons: ^0.1.2
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+
+flutter:
+  uses-material-design: true
+  assets:
+    - images/pic1.jpg
+    - images/pic2.jpg
+    - images/pic3.jpg

examples/layout/sizing/test/widget_test.dart

@@ -0,0 +1,20 @@
+// This is a basic Flutter widget test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility that Flutter provides. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:layout/main.dart';
+
+void main() {
+  testWidgets('Counter increments smoke test', (WidgetTester tester) async {
+    // Build our app and trigger a frame.
+    await tester.pumpWidget(MyApp());
+
+    expect(find.text('Flutter layout demo'), findsOneWidget);
+    // TODO: test more app features.
+  });
+}