在values.xml文件中已经使用不兼容的格式定义了属性“主题”

Question

我正在开发针对Android 8.1的Android Xamarin应用。

在安装 Xamarin Facebook Android 和必需的依赖项后，我得到了一个例外：

  

属性“主题”已使用不兼容的格式定义

values.xml是从某个地方（不确定在哪里）自动生成的，我尝试重命名其中的“ theme”属性，但没有帮助！

有人有任何建议吗？任何帮助将不胜感激。

修改

这是我项目中所有已安装的软件包：

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Bolts" version="1.4.0.1" targetFramework="monoandroid81" />
  <package id="ExifLib.PCL" version="1.0.1" targetFramework="monoandroid5" />
  <package id="FSharp.Core" version="4.0.0.1" targetFramework="monoandroid51" />
  <package id="FSharp.Data" version="2.2.5" targetFramework="monoandroid51" />
  <package id="Microsoft.AppCenter" version="1.5.0" targetFramework="monoandroid51" />
  <package id="Microsoft.AppCenter.Analytics" version="1.5.0" targetFramework="monoandroid51" />
  <package id="Microsoft.AppCenter.Crashes" version="1.5.0" targetFramework="monoandroid51" />
  <package id="Microsoft.Bcl" version="1.1.10" targetFramework="monoandroid51" />
  <package id="Microsoft.Bcl.Async" version="1.0.168" targetFramework="monoandroid5" />
  <package id="Microsoft.Bcl.Build" version="1.0.21" targetFramework="monoandroid51" />
  <package id="Microsoft.CSharp" version="4.3.0" targetFramework="monoandroid51" />
  <package id="Microsoft.Net.Http" version="2.2.29" targetFramework="monoandroid51" />
  <package id="Microsoft.NETCore.Platforms" version="1.1.0" targetFramework="monoandroid51" />
  <package id="Microsoft.Win32.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="modernhttpclient" version="2.4.3.2" targetFramework="monoandroid51" />
  <package id="MvvmCross.Community.Plugin.Sqlite" version="3.1.1" targetFramework="monoandroid51" />
  <package id="MvvmCross.HotTuna.CrossCore" version="3.5.1" targetFramework="monoandroid5" />
  <package id="MvvmCross.PortableSupport" version="3.5.1" targetFramework="monoandroid5" />
  <package id="NETStandard.Library" version="1.6.1" targetFramework="monoandroid51" />
  <package id="Newtonsoft.Json" version="10.0.3" targetFramework="monoandroid51" />
  <package id="PCLStorage" version="1.0.2" targetFramework="monoandroid5" />
  <package id="PlugPdf.Android" version="2.9.25" targetFramework="monoandroid51" />
  <package id="SkyEpub.Android" version="1.1.5661.19097" targetFramework="monoandroid5" />
  <package id="SQLite.Net.Async-PCL" version="3.1.1" targetFramework="monoandroid51" />
  <package id="SQLite.Net.Core-PCL" version="3.1.1" targetFramework="monoandroid51" />
  <package id="SQLite.Net.Platform.XamarinAndroid" version="2.4.1" targetFramework="monoandroid81" />
  <package id="SQLite.Net.Platform.XamarinAndroidN" version="3.1.1" targetFramework="monoandroid81" />
  <package id="SQLite.Net-PCL" version="3.1.1" targetFramework="monoandroid81" />
  <package id="SQLiteNetExtensions-MvvmCross" version="1.2.5" targetFramework="monoandroid51" />
  <package id="sqlite-net-pcl" version="1.5.231" targetFramework="monoandroid81" />
  <package id="SQLitePCLRaw.bundle_green" version="1.1.11" targetFramework="monoandroid81" />
  <package id="SQLitePCLRaw.core" version="1.1.11" targetFramework="monoandroid81" />
  <package id="SQLitePCLRaw.lib.e_sqlite3.android" version="1.1.11" targetFramework="monoandroid81" />
  <package id="SQLitePCLRaw.provider.e_sqlite3.android" version="1.1.11" targetFramework="monoandroid81" />
  <package id="Square.OkHttp" version="2.7.5.0" targetFramework="monoandroid51" />
  <package id="Square.OkIO" version="1.6.0.0" targetFramework="monoandroid51" />
  <package id="System.AppContext" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Collections" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Collections.Concurrent" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.ComponentModel.TypeConverter" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Console" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Diagnostics.Debug" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Diagnostics.Tools" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Diagnostics.Tracing" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Globalization" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Globalization.Calendars" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.IO" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.IO.Compression" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.IO.Compression.ZipFile" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.IO.FileSystem" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.IO.FileSystem.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Linq" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Linq.Expressions" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Net.Http" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Net.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Net.Sockets" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.ObjectModel" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Reflection" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Reflection.Extensions" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Reflection.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Resources.ResourceManager" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.Extensions" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.Handles" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.InteropServices" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.InteropServices.RuntimeInformation" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.Numerics" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.Serialization.Formatters" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Runtime.Serialization.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Security.Cryptography.Algorithms" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Security.Cryptography.Encoding" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Security.Cryptography.Primitives" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Security.Cryptography.X509Certificates" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Text.Encoding" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Text.Encoding.Extensions" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Text.RegularExpressions" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Threading" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Threading.Tasks" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Threading.Timer" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Xml.ReaderWriter" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Xml.XDocument" version="4.3.0" targetFramework="monoandroid51" />
  <package id="System.Xml.XmlDocument" version="4.3.0" targetFramework="monoandroid51" />
  <package id="Xamarin.Android.Arch.Core.Common" version="1.0.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Arch.Lifecycle.Common" version="1.0.3" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Arch.Lifecycle.Runtime" version="1.0.3" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Animated.Vector.Drawable" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Annotations" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Compat" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Core.UI" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Core.Utils" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.CustomTabs" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Fragment" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.Media.Compat" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.v4" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.v7.AppCompat" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.v7.CardView" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Android.Support.v7.MediaRouter" version="20.0.0" targetFramework="monoandroid51" />
  <package id="Xamarin.Android.Support.Vector.Drawable" version="27.0.2" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.AppLinks.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Common.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Core.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Login.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Messenger.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Places.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.Facebook.Share.Android" version="4.40.0" targetFramework="monoandroid81" />
  <package id="Xamarin.FFImageLoading" version="1.1.3" targetFramework="monoandroid5" />
  <package id="Xamarin.Forms.Labs.Cryptography" version="1.2.0" targetFramework="monoandroid51" />
  <package id="Xamarin.Google.ZXing.Core" version="3.3.0" targetFramework="monoandroid81" />
  <package id="Xamarin.GooglePlayServices" version="19.0.0.1" targetFramework="monoandroid51" />
  <package id="YouScribe.Rest" version="3.0.2463" targetFramework="monoandroid81" />
  <package id="YouScribe.Rest.Internal" version="3.0.2623" targetFramework="monoandroid81" />
  <package id="YouScribe.Rest.MobileApp" version="1.30.0" targetFramework="monoandroid81" />
  <package id="YouScribe.SNCF.Rest" version="2.0.20190102.1" targetFramework="monoandroid81" />
  <package id="Zlib.Portable" version="1.10.0" targetFramework="monoandroid51" />
</packages>