颤振背景图像

Question

我对flutter非常陌生，我正在做一个有趣的应用程序。我想添加一个背景图像到我的应用程序，但我找不到如何。我知道我必须把它放在buildcontext上下文中，但我找不到怎么放。这是我的代码：

import 'package:audioplayers/audio_cache.dart';
import 'package:audioplayers/audioplayers.dart';
import 'package:flutter/material.dart';

typedef void OnError(Exception exception);

void main() {
  runApp(new MaterialApp(debugShowCheckedModeBanner: false,home:  LocalAudio()));
}

class LocalAudio extends StatefulWidget {
  @override
  _LocalAudio createState() =>  _LocalAudio();
}


class _LocalAudio extends State<LocalAudio> {
  Duration _duration = new Duration();
  Duration _position = new Duration();
  AudioPlayer advancedPlayer;
  AudioCache audioCache;

  @override
  void initState() {
    super.initState();
    initPlayer();
 }

  void initPlayer() {
    advancedPlayer = new AudioPlayer();
    audioCache = new AudioCache(fixedPlayer: advancedPlayer);

    advancedPlayer.durationHandler = (d) => setState(() {
      _duration = d;
    });

    advancedPlayer.positionHandler = (p) => setState(() {
      _position = p;
    });
  }

  String localFilePath;

  Widget _tab(List<Widget> children) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        Container(
          padding: EdgeInsets.all(16.0),
          child: Column(
            children: children
                .map((w) => Container(child: w, padding: EdgeInsets.all(6.0)))
                .toList(),
          ),
        ),
      ],
    );
  }

  Widget _btn(String txt, VoidCallback onPressed) {
    return ButtonTheme(
      minWidth: 48.0,
      child: Container(
        width: 150,
        height: 150,
        child: RaisedButton(
            shape:
            RoundedRectangleBorder(borderRadius: BorderRadius.circular(25)),
            child: Text(txt),
            color: Colors.greenAccent[900],
            textColor: Colors.white,
            onPressed: onPressed),
      ),
    );
  }



  Widget LocalAudio() {
    return _tab([
      _btn('Play', () => audioCache.play('bruh.mp3')),
    ]);
  }

  void seekToSecond(int second) {
    Duration newDuration = Duration(seconds: second);

    advancedPlayer.seek(newDuration);
  }

  @override
  Widget build(BuildContext context) {
    return DefaultTabController(
      length: 1,
      child: Scaffold(
        backgroundColor: Colors.white,
        appBar: AppBar(
          elevation: 1.0,
          backgroundColor: Colors.teal,
          title: Center(child: Text('BRUH')),
        ),
        body: TabBarView(
          children: [LocalAudio()],
        ),
      ),
    );
  }
}

Answer 1

我只需将脚手架的主体设置为一个Stack()，然后在堆栈的底部放置一个图像。应该是这样的。

@override
  Widget build(BuildContext context) {
    return DefaultTabController(
      length: 1,
      child: Scaffold(
        backgroundColor: Colors.white,
        appBar: AppBar(
          elevation: 1.0,
          backgroundColor: Colors.teal,
          title: Center(child: Text('BRUH')),
        ),
        body: Stack(
          children: [
            Image.asset('assets/images/background.jpg'),
            TabBarView(
              children: [LocalAudio()],
            ),
          ]
        );

      ),