Showcase.withwidget always gives me Null check operator used on a null value

[mhilalsh]

I'm trying to use the Showcase.withwidget to create a container because I want to add a skip button to the showcase, but every time I try to use the showcase.withwidget I get "Null check operator used on a null value",
my code snippet :

Showcase.withWidget(
key: _one,
shapeBorder: CircleBorder(),
container: Container(
height: 200,
width: 200,
child: Row(
children: [
Text("..."),
ElevatedButton(onPressed: (){
ShowCaseWidget.of(context).dismiss();
}, child: Text("skip"))
],
),
),
child: _customDropDownMenu,
),

[mhilalsh]

Hi @vatsaltanna can you help me with this, please?

[BirjuVachhani]

@mhilalsh Can you please share stacktrace?

[mhilalsh]

@BirjuVachhani sorry for the late response,
here's my stacktrace :

======== Exception caught by widgets library =======================================================
The following _CastError was thrown building ToolTipWidget(dirty, dependencies: [_EffectiveTickerMode], state: _ToolTipWidgetState#559ef(ticker active)):
Null check operator used on a null value

The relevant error-causing widget was:
MaterialApp MaterialApp:file:///.../lib/main.dart:14:14
When the exception was thrown, this was the stack:
#0 _ToolTipWidgetState._getSpace (package:showcaseview/src/tooltip_widget.dart:168:68)
#1 _ToolTipWidgetState.build (package:showcaseview/src/tooltip_widget.dart:356:19)
#2 StatefulElement.build (package:flutter/src/widgets/framework.dart:4705:27)
#3 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4588:15)
#4 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4763:11)
#5 Element.rebuild (package:flutter/src/widgets/framework.dart:4311:5)
#6 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4566:5)
#7 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4754:11)
#8 ComponentElement.mount (package:flutter/src/widgets/framework.dart:4561:5)
#9 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3631:14)
#10 MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6261:36)
#11 MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:6272:32)
#12 Element.inflateWidget (package:flutter/src/widgets/framework.dart:3631:14)
#13 Element.updateChild (package:flutter/src/widgets/framework.dart:3380:20)
#14 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4613:16)
#15 Element.rebuild (package:flutter/src/widgets/framework.dart:4311:5)
#16 ProxyElement.update (package:flutter/src/widgets/framework.dart:4943:5)
#17 Element.updateChild (package:flutter/src/widgets/framework.dart:3370:15)
#18 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4613:16)
#19 Element.rebuild (package:flutter/src/widgets/framework.dart:4311:5)
#20 StatelessElement.update (package:flutter/src/widgets/framework.dart:4669:5)
#21 Element.updateChild (package:flutter/src/widgets/framework.dart:3370:15)
#22 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4613:16)
#23 StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4763:11)
#24 Element.rebuild (package:flutter/src/widgets/framework.dart:4311:5)
#25 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2578:33)
#26 WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:882:21)
#27 RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:363:5)
#28 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1145:15)
#29 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1082:9)
#30 SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:996:5)
#34 _invoke (dart:ui/hooks.dart:150:10)
#35 PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:270:5)
#36 _drawFrame (dart:ui/hooks.dart:114:31)
(elided 3 frames from dart:async)

[mhilalsh]

@BirjuVachhani @vatsaltanna FYI Showcase.withWidget throws this exception when I try to wrap a custom widget in it like this custom drop down menu it's a separated widget that I created and included in my login page, but it works fine if I try to wrap any other normal widgets in it.

[mhilalsh]

it worked with me I guess my problem was in the parameters that I gave to the showcase.withwidget here's my code :
Showcase.withWidget(
key: _one,
width: double.infinity,
height: 150,
container: Container(
width: MediaQuery.of(context).size.width - 24,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(10),
color: Colors.white),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
'...'),
),
TextButton(
onPressed: _skipShowCase,
child: Text('Skip Tutorial'),
)
],
),
),
child: _customDropDownMenu,
),