onPressed "invalid constant value" error in Flutter

Question

There appears to be nothing wrong with the code I have for my ElevatedButton, but It's giving me this error:

        TextButton(
          onPressed: () { },
          child: Text('TextButton'),  
        )

This is even posted from the official Flutter website.

Any idea why it's doing this?

Answer 1

It's suspected that your button is a child of a widget that's marked as constant widget, if so, just remove const keyword from parents of that button.

That's because onPressed() can't be declared on a constant scope.