How do I resolve 'Id does not exist' error?

Question

So I am building a calculator with flutter and after changing some of my code, I have been getting this error whenever I hot restart, I get this error:

======== Exception caught by Flutter framework =====================================================
The following assertion was thrown during a service extension callback for "ext.flutter.inspector.setSelectionById":
Id does not exist.

When the exception was thrown, this was the stack: 
#0      WidgetInspectorService.toObject (package:flutter/src/widgets/widget_inspector.dart:1283:7)
#1      WidgetInspectorService.setSelectionById (package:flutter/src/widgets/widget_inspector.dart:1345:25)
#2      WidgetInspectorService._registerServiceExtensionWithArg.<anonymous closure> (package:flutter/src/widgets/widget_inspector.dart:864:35)
#3      WidgetInspectorService._registerServiceExtensionWithArg.<anonymous closure> (package:flutter/src/widgets/widget_inspector.dart:861:17)
#4      BindingBase.registerServiceExtension.<anonymous closure> (package:flutter/src/foundation/binding.dart:597:32)
...

====================================================================================================

I have no clue what the error means and I cant find and answer to it anywhere. The only thing I can infer is that it is possibly something with the inspector due to "ext.flutter.inspector.setSelectionById" but I honestly have no idea. I also believe it might not be to do with my code since it doesn't reference anything in there. I would extremely appreciate if anyone could at least help me understand the error. If you need more details, just ask me.

Answer 1

The error was probably due to Flutter Dev Tools being open.

Answer 2

I got this error when I tried to show a CupertinoTimerPicker inside a SimpleDialog. I solved it by wrapping the CupertinoTimerPicker in a sized box with a defined height and width:

Center(
              child: SizedBox(
                height: 200,
                width: 200,
                child: CupertinoTimerPicker(
                  initialTimerDuration: tempDuration,
                  onTimerDurationChanged: (value) {
                    print(value.toString());
                    tempDuration = value;
                  },
                ),
              ),
            ),