Flutter基础-FloatingActionButton

Sample

Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(
      title: Text('Floating Action Button Sample'),
    ),
    body: Center(
      child: Text('Press the button below!')
    ),
    floatingActionButton: FloatingActionButton(
      onPressed: () {
        // Add your onPressed code here!
      },
      child: Icon(Icons.thumb_up),
      backgroundColor: Colors.pink,
    ),
  );
}

Sample in an App

// Flutter code sample for material.FloatingActionButton.1

// This example shows how to make a simple [FloatingActionButton] in a
// [Scaffold], with a pink [backgroundColor] and a thumbs up [Icon].

import 'package:flutter/material.dart';

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

/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: MyStatelessWidget(),
    );
  }
}

/// This is the stateless widget that the main application instantiates.
class MyStatelessWidget extends StatelessWidget {
  MyStatelessWidget({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Floating Action Button Sample'),
      ),
      body: Center(child: Text('Press the button below!')),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          // Add your onPressed code here!
        },
        child: Icon(Icons.thumb_up),
        backgroundColor: Colors.pink,
      ),
    );
  }
}