beforeValueChange property
It is a callback function which accepts component's future value as a parameter and returns a Future.
It is called every-time before a component's value changes. The promise, if and when resolved, triggers the execution of the component's query and if rejected, kills the query execution. This method can act as a gatekeeper for query execution, since it only executes the query after the provided promise has been resolved.
For example:
Future (value) {
// called before the value is set
// returns a [Future]
// update state or component props
return Future.value(value);
// or Future.error()
}
Implementation
final Future Function(dynamic value)? beforeValueChange;