helper_options 0.1.0+4 helper_options: ^0.1.0+4 copied to clipboard
A library to use the option of any object.
Helper options #
A generic package created to handle your objects, widgets in a nicer way.
Explanation with examples: #
It is a generic class to determine the state of the object:
// A sample class object
class User {
const User(this.username);
final String username;
}
```
traditional way:
```dart
// in your business logic
User? user = await api.getUser();
if (user == null) {
// do this
final userName = user.username;
} else {
// do this
}
with helper_options:
// in your business logic
Option<User>? user = await api.getUser();
if (user.isPresent) {
// do this while getting value as
final userName = user.value.username;
} else {
// do this
}
Looks cool nah!!!
You may explore options too:
// this option class comes with other helper methods like
user.empty(); // Creates an empty Option.
user.filter(); // Returns an Option with this Option's value, if there is a value present and it matches the predicate. Otherwise, returns an empty Option.
user.flatMap(); // Returns an Option provided by applying the mapper to this Option's value,if present. Otherwise, returns an empty Option.
user.orElse(); // Returns this Option's value, if present. Otherwise, returns other.
user.orNull(); // Returns this Option's value, if present. Otherwise, returns null.
user.orElseThrow(); // Returns this Option's value, if present. Otherwise, throws the result of calling supplyError().
user.ifPresent(final val){
// Invokes consume() with this Option's value, if present.
// Otherwise, if orElse is passed, invokes it, otherwise does nothing.
}
OptionWidget: #
In another example, we are going to have a super OptionWidget
to generate the Widget as your data is there:
Traditional way:
class CustomWidget extends StatelessWidget {
const CustomWidget({this.user});
final User? user;
bool get isEmptyUser => user == null;
@override
Widget build(final BuildContext context) {
if (isEmptyUser) {
return SizedBox();
}
return childWidget();
}
}
with CustomWidget:
ParentWidget(
child: CustomWidget<User?>(
option: Option.of(user),
empty: final OffStage(), // it is an optional widget to place
builder: (final context, final user) {
return Child();
},
),
),
Note: You can use this function in a nicer way with all the objects including primitive data types or custom one