removeListener method Null safety
- VoidCallback listener
override
Remove a previously registered closure from the list of closures that the object notifies when it is time to repaint.
The CustomPainter implementation merely forwards to the same method on
the Listenable provided to the constructor in the repaint
argument, if
it was not null.
Implementation
@override
void removeListener(VoidCallback listener) => _repaint?.removeListener(listener);