createAsync<TParam, TResult> static method
- Future<
TResult> func(- TParam x
- required TResult initialValue,
- ValueListenable<
bool> ? restriction, - ExecuteInsteadHandler<
TParam> ? ifRestrictedExecuteInstead, - bool includeLastResultInCommandResults = false,
- ErrorFilter? errorFilter,
- bool notifyOnlyWhenValueChanges = false,
- String? debugName,
Creates a Command for an asynchronous handler function with parameter that returns a value
func
: handler function
initialValue
sets the .value
of the Command.
restriction
: ValueListenable<bool>
that can be used to enable/disable the command based on
some other state change. true
means that the Command cannot be executed.
If omitted the command can be executed always except it's already executing
ifRestrictedExecuteInstead
if restriction
is set for the command and its value is true
this function will be called instead of the wrapped function.
This is useful if you want to execute a different function when the command
is restricted. For example you could show a dialog to let the user logg in
if the restriction is because the user is not logged in.
If you don't set this function, the command will just do nothing when it's
restricted.
includeLastResultInCommandResults
will include the value of the last successful execution in
all CommandResult
values unless there is no result. This can be handy if you always want to be able
to display something even when you got an error or while the command is still running.
errorFilter
: overrides the default set by errorFilterDefault.
If false
, Exceptions thrown by the wrapped function won't be caught but rethrown
unless there is a listener on errors or results.
notifyOnlyWhenValueChanges
: the default is that the command notifies it's listeners even
if the value hasn't changed. If you set this to true
the command will only notify
it's listeners if the value has changed.
debugName
optional identifier that is included when you register a globalExceptionHandler
or a loggingHandler
Implementation
static Command<TParam, TResult> createAsync<TParam, TResult>(
Future<TResult> Function(TParam x) func, {
required TResult initialValue,
ValueListenable<bool>? restriction,
ExecuteInsteadHandler<TParam>? ifRestrictedExecuteInstead,
bool includeLastResultInCommandResults = false,
ErrorFilter? errorFilter,
bool notifyOnlyWhenValueChanges = false,
String? debugName,
}) {
return CommandAsync<TParam, TResult>(
func: func,
initialValue: initialValue,
restriction: restriction,
ifRestrictedExecuteInstead: ifRestrictedExecuteInstead,
includeLastResultInCommandResults: includeLastResultInCommandResults,
noReturnValue: false,
errorFilter: errorFilter,
notifyOnlyWhenValueChanges: notifyOnlyWhenValueChanges,
debugName: debugName,
noParamValue: false,
);
}