useState not working with ModalSheet

[anmol-me]

My hook under the build method of main page

final isLoading = useState(false);

Main Page shows a button to show modalsheet

Center(
        child: ElevatedButton(
          onPressed: showModalSheet,
          child: const Text('Show Sheet'),
        ),
      )

Method to show modal sheet
On pressing the Load button, the value of isLoading does get changed but it is not reflecting the change to change Close button to wait button.

    Future showModalSheet() {
      return showModalBottomSheet(
        context: context,
        builder: (context) {
          return Column(
            children: [
              ElevatedButton(
                onPressed: () async {
                  isLoading.value = true;
                  print('${isLoading.value}');

                  await Future.delayed(const Duration(seconds: 5)).then((_) {
                    isLoading.value = false;
                    print('${isLoading.value}');
                  });
                },
                child: const Text('Load'),
              ),
             // Not working here
              isLoading.value
                  ? const TextButton(onPressed: null, child: Text('Wait'))
                  : TextButton(
                      onPressed: () => Navigator.of(context).pop(),
                      child: const Text('Close'),
                    ),
            ],
          );
        },
      );
    }