This store is intentionally configured to validate the data on each update, that is why the validateAfterUpdate parameter is set to
true by default.
There might be special situations where it is reasonable to disable this behaviour by setting validateAfterUpdate to
false and to prefer applying the validation individually within custom handlers, for example if a model should only be validated after the user has completed his input or if metadata is needed for the validation process. Then be aware of the fact, that the call of the validate function actually updates the messages already.
In order for the automatic validation to work, a metadataDefault value must be specified. This is needed due to no specific metadata being present during automatic validation. When calling validate manually, the appropriate metadata can be supplied directly.
If the new data is not passed to the store's state after validating it, the messages are probably out of sync with the actual store's state! This could lead to false assumptions and might produce hard to detect bugs in your application.
default metadata to be used by the automatic validation (where no explicit values are given)
Factory method to create a SimpleHandler that does not take an Action
Connects a Flow to a Handler.
Connects a Flow to a suspendable execute function.
on a Store of nullable data this creates a Store with a nullable parent and non-nullable value. It can be called using a Lens on a non-nullable parent (that can be created by using the @Lenses-annotation), but you have to ensure, that the resulting Store is never used, when it's parent's value is null. Otherwise, a NullPointerException is thrown.