Why im getting this error Warning: Operand of null-aware operation '??' has type 'Color' which excludes null

Im using this package
```
flutter_datetime_picker: ^1.5.1
```
And this is my code
```
String _date = "Please pick Age";

Widget _buildage() {
return Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
Text(
'Enter Age',
style: kLabelStyle,
),
SizedBox(height: 10.0),
Container(
decoration: kBoxDecorationStyle,
alignment: Alignment.centerLeft,
height: 70.0,
child: Container(
child: TextFormField(
initialValue: "haaas",
validator: (val) {
if (val.isEmpty) {
return 'Enter yout Age';
}
if (val.length < 4) {
return 'Enter a username minimun 4 chars long';
}

return null;
},
onChanged: (val) {
setState(() => age = val);
},
onTap: () {
DatePicker.showDatePicker(context,
theme: DatePickerTheme(
containerHeight: 210.0,
),
showTitleActions: true,
minTime: DateTime(2000, 1, 1),
maxTime: DateTime(2022, 12, 31), onConfirm: (date) {
setState(() {
_date = '${date.year} - ${date.month} - ${date.day}';
});
}, currentTime: DateTime.now(), locale: LocaleType.en);
},
readOnly: true,
decoration: InputDecoration(
border: InputBorder.none,
contentPadding: EdgeInsets.only(top: 14.0),
prefixIcon: Icon(
Icons.date_range_rounded,
color: Colors.white,
size: 28,
),
hintText: " $_date",
hintStyle: kHintTextStyle,
),
),
),
),
]);
}
```
the error or warning is this
```
../../flutter/.pub-cache/hosted/pub.dartlang.org/flutter_datetime_picker-1.5.1/lib/flutter_datetime_picker.dart:311:32: Warning: Operand of null-aware operation '??' has type 'Color' which excludes null.
- 'Color' is from 'dart:ui'.
color: theme.backgroundColor ?? Colors.white,
^

```
Everything works fine and I dont know why im getting this error . if you need more information please leave a comment. Hope anyone knows how to fix that . If you need any other information please leave also a comment

It's just a warning, so no need to worry. It was fixed with this PR

[To see links please register here]

but apparently didn't make it into the latest deployment.

If you want, pulling from master instead of pub.dev should solve it until a new version is deployed.

flutter_datetime_picker:
git:
url:

[To see links please register here]

ref: master

final ```Color? backgroundColor;```
add this in DatePickerTheme

If you want to get rid of it until a new version is deployed, just change the line `color: theme.backgroundColor ?? Colors.white` to `color:theme.backgroundColor`. Or pull package from master:

flutter_datetime_picker:
git:

[To see links please register here]

That's not an error, it's a warning coming from the `flutter_datetime_picker` package that indicates it hasn't quite updated its code to be fully idiomatic with null safety. Basically, it's using the `??` operator on the off-chance that `theme.backgroundColor` is null, but now that `theme.backgroundColor` is marked as non-nullable, the operator is redundant. It's annoying to have the warning pop up, but it won't affect your app in any way.

Note that the code *has* been properly updated in the [master branch of the package repository](

[To see links please register here]

), so the next time the package is published, the warning will disappear.

**EDIT:** <strike>As of version 1.5.1, this package now officially supports null safety.</strike> The fix was added via pull request after 1.5.1's release, so the next version (1.5.2 or something) should address this issue.

**EDIT 2:** Coming up on a year since the last commit and 14 months since 1.5.1 was published, it's probably safe to assume this package has been abandoned. It's worth noting that, apart from specific functionality that I am not aware of, [`CupertinoDatePicker`](

[To see links please register here]

) in the built-in Flutter library now renders this package obsolete anyway.

For those who for whatever reason want to continue using this package without the warning, you can change the package dependency to point to the master branch of the repository (credit [[1]](

[To see links please register here]

) [[2]](

[To see links please register here]

)):

```yaml
flutter_datetime_picker:
git:
url:

[To see links please register here]

ref: master
```

It's worth noting that this approach could expose your app to breaking changes if the package developer comes back with new commits, as well as vulnerabilities if the repository becomes the target of malicious activity. You would also lose the benefits of using the pub package manager, such as version management and automatic upgrades. As such, I would highly recommend anyone still using this package to migrate to Flutter's `CupertinoDatePicker` above.