I have a project was made before null safety, now the code has a lot of errors I was fixed all error except this two errors shown below, and I'm not sure what should I do about this

The first error: The first error:

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The Second error: The Second error

Thanks in advance

CodePudding user response：

You can use a null-able value like String? _token. Because it can be a null value before initializing the value.
Or you can use a late keyword to init later, but you shouldn't use this before init.

For more info, reference the Null safety in Dart video.