demo中使用FlutterBoostApp包裹的 appBuilder, 怎么指定自己的widget ???

Widget appBuilder(Widget home) {
return MaterialApp(
home: home,
debugShowCheckedModeBanner: false,

///必须加上builder参数，否则showDialog等会出问题
builder: (_, __) {
return home;
},
);
}

@override
Widget build(BuildContext context) {
return FlutterBoostApp(
routeFactory,
appBuilder: appBuilder,
);
}

如上,是demo的写法...我自己的项目,,我把appBuilder内的 home 改成自己的根widget,为何 一运行 ,代码就报错...

======== Exception caught by scheduler library =====================================================
The following _CastError was thrown during a scheduler callback:
Null check operator used on a null value

When the exception was thrown, this was the stack:
#0 BoostChannel.addEventListener (package:flutter_boost/src/boost_channel.dart:32:21)
#1 FlutterBoostAppState._addAppLifecycleStateEventListener (package:flutter_boost/src/flutter_boost_app.dart:119:10)
#2 FlutterBoostAppState.initState. (package:flutter_boost/src/flutter_boost_app.dart:108:7)
#3 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1145:15)
#4 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1090:9)
#5 SchedulerBinding.scheduleWarmUpFrame. (package:flutter/src/scheduler/binding.dart:863:7)
(elided 11 frames from class _RawReceivePortImpl, class _Timer, dart:async, and dart:async-patch)
====================================================================================================

这怎么办???

Start with the custom appBuilder and FlutterBoostApp usage shown in the report, then inspect boost_channel.dart:32 and flutter_boost_app.dart:108-119 around the lifecycle listener. Reproduce the scheduler callback failure and determine why replacing home produces a null value; done means the custom root widget starts without the reported cast error.

Written by the indexing model from the issue text.