android 接入该包后，运行有报错

[zlei123456]

报错文本：
2020-05-26 18:01:17.828 16872-16872/com.example.hello E/MethodChannel#flutter/platform_views: Failed to handle method call
java.lang.NullPointerException: Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on a null object reference
at io.flutter.embedding.engine.systemchannels.PlatformViewsChannel$1.create(PlatformViewsChannel.java:87)
at io.flutter.embedding.engine.systemchannels.PlatformViewsChannel$1.onMethodCall(PlatformViewsChannel.java:59)
at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:226)
at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:631)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:332)
at android.os.Looper.loop(Looper.java:168)
at android.app.ActivityThread.main(ActivityThread.java:6878)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:876)
2020-05-26 18:01:17.966 16872-16901/com.example.hello E/flutter: [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: PlatformException(error, Attempt to invoke virtual method 'double java.lang.Double.doubleValue()' on a null object reference, null)
#0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:569:7)
#1 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:156:18)

#2 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:329:12)
#3 PlatformViewsService.initUiKitView (package:flutter/src/services/platform_views.dart:162:41)
#4 _UiKitViewState._createNewUiKitView (package:flutter/src/widgets/platform_view.dart:623:71)
#5 _UiKitViewState._initializeOnce (package:flutter/src/widgets/platform_view.dart:573:5)
#6 _UiKitViewState.didChangeDependencies (package:flutter/src/widgets/platform_view.dart:583:5)
#7 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4661:12)
#8 ComponentElement.mount (package:flutter/src/widgets/framework.dart:4476:5)
#9 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#10 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#11 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4527:16)
#12 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4675:11)
#13 Element.rebuild (package:flutter/src/widgets/framework.dart:4218:5)
#14 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4481:5)
#15 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4666:11)
#16 ComponentElement.mount (package:flutter/src/widgets/framework.dart:4476:5)
#17 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#18 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#19 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4527:16)
#20 Element.rebuild (package:flutter/src/widgets/framework.dart:4218:5)
#21 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4481:5)
#22 ComponentElement.mount (package:flutter/src/widgets/framework.dart:4476:5)
#23 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#24 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#25 SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5830:14)
#26 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#27 MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5947:32)
#28 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#29 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#30 SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5830:14)
#31 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#32 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#33 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4527:16)
#34 Element.rebuild (package:flutter/src/widgets/framework.dart:4218:5)
#35 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4481:5)
#36 ComponentElement.mount (package:flutter/src/widgets/framework.dart:4476:5)
#37 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#38 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#39 SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5830:14)
#40 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3446:14)
#41 Element.updateChild (package:flutter/src/widgets/framework.dart:3214:18)
#42 SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:5830:14)
#43 Element.inflateWidget (package:flutter/src

感觉是插件没有被正确加入

flutter 版本：Flutter 1.17.1

除了mainActivity.kt中加入了
class MainActivity: FlutterActivity() {
override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
GeneratedPluginRegistrant.registerWith(flutterEngine)
}
}
其他没有改动。是不是缺少什么配置？