MutationBuilder<TData, TVariables, TOnMutateResult> class Mutations

Builds its subtree from a mutation's result, and hands the builder the MutationController that starts a run.

MutationBuilder(
  options: MutationOptions.simple(
    mutationFn: (String name) => api.rename(id, name),
  ),
  builder: (context, rename) => switch (rename.value) {
    MutationPending() => const CircularProgressIndicator(),
    MutationError(:final error) => Text('Could not rename: $error'),
    _ => TextButton(
        onPressed: () => rename.mutate('Kitchen'),
        child: const Text('Rename'),
      ),
  },
)

The widget owns the controller from its first build until it is disposed; do not dispose the one builder is handed. Disposing it does not cancel a run in flight — the mutation finishes and its options' callbacks run — so a write the user started is not lost when the widget goes. Call MutationController.cancel first when it should be.

The type arguments come from options: MutationOptions.simple, for a mutation without an onMutate step, infers them from mutationFn.