import 'package:flutter/material.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Tap Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Tap Demo'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      body: new ListView.builder(
        itemBuilder: (context, index) {
          return Container(
            margin: const EdgeInsets.all(8.0),
            child: ConstrainedBox(
              constraints: BoxConstraints.expand(
                height: 50.0,
              ),
              child: FlatButton(
                child: Text('TAP ME'),
                onPressed: () {},
              ),
            ),
          );
        },
      ),
    );
  }
}

☆ flutter doctor -v
[✓] Flutter (Channel master, v0.5.7-pre.83, on Mac OS X 10.13.5 17F77, locale en-US)
    • Flutter version 0.5.7-pre.83 at /Users/albertlardizabal/dev/flutter
    • Framework revision b931640c1d (10 hours ago), 2018-07-10 06:51:12 +0100
    • Engine revision 6fe748490d
    • Dart version 2.0.0-dev.63.0.flutter-4c9689c1d2

[✓] Android toolchain - develop for Android devices (Android SDK 27.0.3)
    • Android SDK at /Users/albertlardizabal/Library/Android/sdk
    • Android NDK at /Users/albertlardizabal/Library/Android/sdk/ndk-bundle
    • Platform android-27, build-tools 27.0.3
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)
    • All Android licenses accepted.

[✓] iOS toolchain - develop for iOS devices (Xcode 9.4.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.4.1, Build version 9F2000
    • ios-deploy 1.9.2
    • CocoaPods version 1.5.3

[✓] Android Studio (version 3.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin version 26.0.1
    • Dart plugin version 173.4700
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)

[✓] IntelliJ IDEA Community Edition (version 2018.1.5)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    • Flutter plugin version 26.0.2
    • Dart plugin version 181.4892.1