CODEWITHSUNDEEP
androidflutterdartflutter-webdart-null-safety
Insta Devoloper__
Insta Devoloper__

Reputation: 17

The value 'null' can't be assigned to the parameter type 'Offset' because 'Offset' is not nullable

I've been following a tutorial on youtube for flutter. https://www.youtube.com/watch?v=Zv5T2C1oKus. I'm new to flutter and dart btw. I don't understand this error message.

lib/main.dart:91:36: Error: The value 'null' can't be assigned to the parameter type 'Offset' because 'Offset' is not nullable.

  • 'Offset' is from 'dart:ui'. points.add(null); ^

here is my code

error comes from "points.add(null)"

enter image description here

Upvotes: 0

Views: 1148

Answers (2)

flyingotter
flyingotter

Reputation: 56

In the video you linked, there is a check whether points[x] is null, so I assume the elements of points should be nullable. You can achieve this with

List<Offset?> points = [];

(instead of List<Offset> points = [];). The added questionmark makes it possible for elements of the list to be either a instance of the class Offset or the value null.

Upvotes: 4

bakatsuyuki
bakatsuyuki

Reputation: 166

The points is non-nullable list.

So this time, it can be solved with to remove points.add(null); inside onPanEnd. (Or add non-null Offset.)

Upvotes: 0

Related Questions