App database is not deleted on app uninstall Flutter

Question

In my app I just realized that on Android Sembast db is not deleted when I uninstall the app, on iOS it does get deleted. Looking at other answers here I saw that in order to prevent Android backup there is the flag android:allowBackup="false" to be set in AndroidManifest.xml. So I did for the Manifest in android/main/app. Nothing changed. Upon app uninstall and reinstall db is still there. As my phone uses Android 7.0 API 24 I guess this flag will have affect on next installs, but I'll have to remove db manually. this time. Did I add this flag correctly?

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.vinny.fixit_cloud_biking">

    <!-- io.flutter.app.FlutterApplication is an android.app.Application that
         calls FlutterMain.startInitialization(this); in its onCreate method.
         In most cases you can leave this as-is, but you if you want to provide
         additional functionality it is fine to subclass or reimplement
         FlutterApplication and put your custom class here. -->
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />

    <application
        android:name="io.flutter.app.FlutterApplication"

        android:label="fixit"
        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"
            android:allowBackup="false">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationReceiver" />
        <receiver android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"/>
                <action android:name="android.intent.action.MY_PACKAGE_REPLACED"/>
            </intent-filter>
        </receiver>
        <!-- Don't delete the meta-data below.
             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
        <meta-data
            android:name="flutterEmbedding"
            android:value="2" />
    </application>
</manifest>

I tried to look for the db folder in the phone directory Android/data/com.vinny.fixit_cloud_biking/files but there is only a Pictures folder. Where do I get to delete the old db? this is the path declared in the singleton final dbPath = join(appDocumentDir.path, 'device.db');

Answer 1

Try to add android:allowBackup="false" at the <application> level not the <activity> level

 <application
        android:name="io.flutter.app.FlutterApplication"
        android:allowBackup="false"