concrete_ class_ with_ abstract_ member
'{0}' must have a method body because '{1}' isn't abstract.
Description
#The analyzer produces this diagnostic when a member of a concrete class is found that doesn't have a concrete implementation. Concrete classes aren't allowed to contain abstract members.
Example
#
The following code produces this diagnostic because
m
is an abstract
method but
C
isn't an abstract class:
class C {
void m();
}
Common fixes
#If it's valid to create instances of the class, provide an implementation for the member:
class C {
void m() {}
}
If it isn't valid to create instances of the class, mark the class as being abstract:
abstract class C {
void m();
}
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Page last updated on 2025-9-1. View source or report an issue.