Getting Black screen as splash screen on flutter app startup

My AndroidManifest.xml :

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.flutter_application_1">
   <application
        android:label="flutter_application_1"
        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">
            
            <meta-data
              android:name="io.flutter.embedding.android.NormalTheme"
              android:resource="@style/NormalTheme"
              />
            <meta-data
              android:name="io.flutter.embedding.android.SplashScreenDrawable"
              android:resource="@drawable/launch_background"
              />
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
    </application>
</manifest>

My launch_background.xml :(I have given white color but still getting black screen)

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@android:color/white" />
    <item>
        <bitmap
            android:gravity="center"
            android:src="@mipmap/ic_launcher" />
    </item> 
</layer-list>

My style.xml :

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
       <item name="android:windowBackground">@drawable/launch_background</item>
    </style>
    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
       <item name="android:windowBackground">?android:colorBackground</item>
    </style>
</resources>

res folder :

flutter run --verbose : (Report) Verbose Report

Remaining everything is working fine, the only problem that I am facing is with this Launch/Splash Screen. Please help me out to figure it out.