Classes and mixins can only implement other classes and mixinsDRT-W1384
The analyzer produces this diagnostic when a name used in the implements
clause of a class or mixin declaration is defined to be something other
than a class or mixin.
Example
The following code produces this diagnostic because x
is a variable
rather than a class or mixin:
var x;
class C implements x {}
Common fixes
If the name is the name of an existing class or mixin that's already being imported, then add a prefix to the import so that the local definition of the name doesn't shadow the imported name.
If the name is the name of an existing class or mixin that isn't being imported, then add an import, with a prefix, for the library in which it's declared.
Otherwise, either replace the name in the implements
clause with the name
of an existing class or mixin, or remove the name from the implements
clause.