Flutter 首次运行应用程序时显示黑屏的颤振

无法解决我的问题

在将颤振通道切换到

master

并升级颤振后，我的应用程序无法解决此问题。我怎样才能解决这个问题

flutter doctor -v
[√] Flutter (Channel master, 1.22.0-10.0.pre.139, on Microsoft Windows [Version 10.0.19041.450], locale en-US)
    • Flutter version 1.22.0-10.0.pre.139 at F:\software\flutter
    • Framework revision 3dfbdac6f4 (3 hours ago), 2020-09-11 11:40:03 -0400
    • Engine revision 983b0ef164
    • Dart version 2.10.0 (build 2.10.0-116.0.dev)

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.0)
    • Android SDK at F:\software\sdk
    • Platform android-30, build-tools 30.0.0
    • ANDROID_HOME = F:\software\sdk
    • Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)

[√] Android Studio (version 4.0)
    • Android Studio at C:\Program Files\Android\Android Studio
    • Flutter plugin version 49.0.2
    • Dart plugin version 193.7547
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)

[√] Connected device (1 available)
    • WAS LX1A (mobile) • 2XJDU17C14006203 • android-arm64 • Android 8.0.0 (API 26)

新颤振应用的内容：

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

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

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

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), 
    );
  }
}

launch\u background.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Modify this file to customize your launch splash screen -->
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@android:color/white" />

    <!-- You can insert your own image assets here -->
     <item>
        <bitmap
            android:gravity="center"
            android:src="@mipmap/ic_launcher" />
    </item>
</layer-list>

<application
    android:name="io.flutter.app.FlutterApplication"
    android:label="instaluxury"
    android:icon="@mipmap/ic_launcher">
    <activity
        android:name=".MainActivity"
        android:launchMode="singleTop"
        android:theme="@style/LaunchTheme"
        android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
        android:hardwareAccelerated="true"
        android:windowSoftInputMode="adjustResize">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
    <!-- Don't delete the meta-data below.
         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
    <meta-data
        android:name="io.flutter.app.android.SplashScreenUntilFirstFrame"
        android:value="true" />
</application>

---

除非我遗漏了什么：你的应用程序会显示一个黑屏，直到它被加载并准备好显示我的主页。如果没有包含启动屏幕，这是正常行为。您可以在官方文档中阅读关于添加闪屏的内容：

在我的代码中更改android实现后，我仍然有这个问题。根据您在链接问题中的评论和您在此处的评论，我只能得出结论，您没有包括闪屏。如果有，请更新您的问题，说明您是如何尝试这样做的，这样我们就可以看到问题所在。如果你还没有，那么请按照我答案中的链接。

<application
    android:name="io.flutter.app.FlutterApplication"
    android:label="instaluxury"
    android:icon="@mipmap/ic_launcher">
    <activity
        android:name=".MainActivity"
        android:launchMode="singleTop"
        android:theme="@style/LaunchTheme"
        android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
        android:hardwareAccelerated="true"
        android:windowSoftInputMode="adjustResize">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
    <!-- Don't delete the meta-data below.
         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
    <meta-data
        android:name="io.flutter.app.android.SplashScreenUntilFirstFrame"
        android:value="true" />
</application>