It looks like you have installed the 'error lens' extension in vs code, please uninstall it

CodePudding user response：

this is a dart analysis warning. either you clear the error by:

1. using const constructor on the widget, on this case is the MaterialApp, since you don't have any changed parameters on the widget:

...
  const MaterialApp(
    ...
  ),
...

or,

2. using VSCode's Quick Fixes and ignoring the errors, like so: