获取到MaterialApp中的navigator创建的Overlay。此时的overlay是全局的，如果当前界面收到某些事件回调导致跳转，会导致卡死。

[ever-deng]

The following assertion was thrown during paint():
RRect argument contained a NaN value.
'dart:ui/painting.dart':
Failed assertion: line 33 pos 10: ''

Either the assertion indicates an error in the framework itself, or we should provide substantially more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
https://github.com/flutter/flutter/issues/new?template=2_bug.md

The relevant error-causing widget was:
GetMaterialApp GetMaterialApp:file:///Users/air/android/yunwei/lib/main.dart:68:16
When the exception was thrown, this was the stack:
#2 _rrectIsValid (dart:ui/painting.dart:33:10)
#3 Path.addRRect (dart:ui/painting.dart:2644:12)
#4 RenderPhysicalModel.paint (package:flutter/src/rendering/proxy_box.dart:2055:44)
#5 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#6 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#7 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#8 RenderOffstage.paint (package:flutter/src/rendering/proxy_box.dart:3835:11)
#9 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#10 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#11 RenderBoxContainerDefaultsMixin.defaultPaint (package:flutter/src/rendering/box.dart:2924:15)
#12 RenderStack.paintStack (package:flutter/src/rendering/stack.dart:654:5)
#13 RenderStack.paint (package:flutter/src/rendering/stack.dart:670:7)
#14 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#15 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#16 _RenderTheatre.paintStack (package:flutter/src/widgets/overlay.dart:894:15)
#17 _RenderTheatre.paint (package:flutter/src/widgets/overlay.dart:912:7)
#18 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#19 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#20 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#21 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#22 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#23 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#24 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#25 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#26 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#27 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#28 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#29 _RenderTheatre.paintStack (package:flutter/src/widgets/overlay.dart:894:15)
#30 _RenderTheatre.paint (package:flutter/src/widgets/overlay.dart:912:7)
#31 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#32 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#33 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#34 _RenderInkFeatures.paint (package:flutter/src/material/material.dart:653:11)
#35 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#36 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#37 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#38 RenderPhysicalModel.paint. (package:flutter/src/rendering/proxy_box.dart:2110:15)
#39 PaintingContext.pushClipRRect (package:flutter/src/rendering/object.dart:564:14)
#40 RenderPhysicalModel.paint (package:flutter/src/rendering/proxy_box.dart:2097:21)
#41 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#42 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#43 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#44 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#45 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#46 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#47 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#48 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#49 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#50 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#51 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#52 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#53 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#54 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#55 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#56 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#57 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#58 RenderProxyBoxMixin.paint (package:flutter/src/rendering/proxy_box.dart:144:15)
#59 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#60 PaintingContext.paintChild (package:flutter/src/rendering/object.dart:253:13)
#61 RenderView.paint (package:flutter/src/rendering/view.dart:216:15)
#62 RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2853:7)
#63 PaintingContext._repaintCompositedChild (package:flutter/src/rendering/object.dart:169:11)
#64 PaintingContext.repaintCompositedChild (package:flutter/src/rendering/object.dart:112:5)
#65 PipelineOwner.flushPaint (package:flutter/src/rendering/object.dart:1137:31)
#66 RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:518:19)
#67 WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:865:13)
#68 RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:381:5)
#69 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1289:15)
#70 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1218:9)
#71 SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:1076:5)
#72 _invoke (dart:ui/hooks.dart:145:13)
#73 PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:338:5)
#74 _drawFrame (dart:ui/hooks.dart:112:31)
(elided 2 frames from class _AssertionError)
The following RenderObject was being processed when the exception was fired: RenderPhysicalModel#f7605 relayoutBoundary=up2
... parentData: (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(115.2, 77.6)
... elevation: 0.0
... color: Color(0x00000000)
... shadowColor: Color(0x00000000)
... shape: BoxShape.rectangle
... borderRadius: BorderRadius.zero
RenderObject: RenderPhysicalModel#f7605 relayoutBoundary=up2
parentData: (can use size)
constraints: BoxConstraints(unconstrained)
size: Size(115.2, 77.6)
elevation: 0.0
color: Color(0x00000000)
shadowColor: Color(0x00000000)
shape: BoxShape.rectangle
borderRadius: BorderRadius.zero
... child: _RenderInkFeatures#40236 relayoutBoundary=up3 NEEDS-PAINT
... parentData: (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(115.2, 77.6)
... child: RenderTransform#e0bb6 relayoutBoundary=up4 NEEDS-PAINT
... parentData: (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(115.2, 77.6)
... transform matrix: [0] 1.0,0.0,0.0,0.0
[1] 0.0,1.0,0.0,0.0
[2] 0.0,0.0,1.0,0.0
[3] 0.0,0.0,0.0,1.0
... origin: null
... alignment: Alignment.centerRight
... textDirection: ltr
... transformHitTests: true
... child: RenderStack#cca47 relayoutBoundary=up5 NEEDS-PAINT
... parentData: (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(115.2, 77.6)
... alignment: AlignmentDirectional.topStart
... textDirection: ltr
... fit: loose
... clipBehavior: antiAlias
... child 1: RenderDecoratedBox#03e3f relayoutBoundary=up6 NEEDS-PAINT
... parentData: not positioned; offset=Offset(0.0, 0.0) (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(115.2, 77.6)
... decoration: ShapeDecoration
... color: Color(0xffffffff)
... shape: RoundedRectangleBorder(BorderSide(color: Color(0x00000000), width: 0.0), BorderRadius.circular(6.3))
... configuration: ImageConfiguration(bundle: PlatformAssetBundle#4d92b(), devicePixelRatio: 2.8, locale: zh_CN, textDirection: TextDirection.ltr, platform: android)
... child 2: RenderTransform#f067f relayoutBoundary=up6 NEEDS-PAINT
... parentData: top=14.6; right=-8.9; offset=Offset(112.1, 14.6) (can use size)
... constraints: BoxConstraints(unconstrained)
... size: Size(12.0, 6.0)
... transform matrix: [0] 0.0,-1.0,0.0,0.0
[1] 1.0,0.0,0.0,0.0
[2] 0.0,0.0,1.0,0.0
[3] 0.0,0.0,0.0,1.0
... origin: null
... alignment: Alignment.center
... textDirection: ltr
... transformHitTests: true