An example of how to load more data when scroll to end of list view using rx_redux.
An example of how to make a instant search and load more data when scroll to end of list view using rx_redux.
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import 'dart:async';
import 'package:rx_redux/rx_redux.dart';
import 'package:rxdart/rxdart.dart';
/// Actions
class Action {
final Todo todo;
final ActionType type;
const Action(this.todo, this.type);
@override
String toString() => 'Action { ${todo.id}, $type }';
}
enum ActionType {
add,
remove,
toggle,
//
added,
removed,
toggled,
}
/// View state
class Todo {
final int id;
final String title;
final bool completed;
const Todo(this.id, this.title, this.completed);
@override
String toString() => 'Todo { $id, $completed }';
}
class ViewState {
final List<Todo> todos;
const ViewState(this.todos);
@override
String toString() => 'ViewState { ${todos.length} }';
}
/// Reducer
ViewState reducer(ViewState vs, Action action) {
switch (action.type) {
case ActionType.add:
return vs;
case ActionType.remove:
return vs;
case ActionType.toggle:
return vs;
case ActionType.added:
return ViewState([...vs.todos, action.todo]);
case ActionType.removed:
return ViewState(
vs.todos.where((t) => t.id != action.todo.id).toList(),
);
case ActionType.toggled:
final todos = vs.todos
.map((t) =>
t.id != action.todo.id ? t : Todo(t.id, t.title, !t.completed))
.toList(growable: false);
return ViewState(todos);
default:
return vs;
}
}
/// Side effects
final SideEffect<Action, ViewState> addTodoEffect = (action$, state) => action$
.where((event) => event.type == ActionType.add)
.map((event) => event.todo)
.flatMap(
(todo) => Rx.timer(
Action(todo, ActionType.added),
const Duration(milliseconds: 300),
),
);
Stream<Action> removeTodoEffect(
Stream<Action> action$,
GetState<ViewState> state,
) {
final executeRemove = (Todo todo) async* {
await Future.delayed(const Duration(milliseconds: 200));
yield Action(todo, ActionType.removed);
};
return action$
.where((event) => event.type == ActionType.remove)
.map((action) => action.todo)
.flatMap(executeRemove);
}
final SideEffect<Action, ViewState> toggleTodoEffect = (action$, state) {
final executeToggle = (Todo todo) async* {
await Future.delayed(const Duration(milliseconds: 500));
yield Action(todo, ActionType.toggled);
};
return action$
.where((event) => event.type == ActionType.toggle)
.map((action) => action.todo)
.flatMap(executeToggle);
};
void main() async {
final store = RxReduxStore(
initialState: ViewState([]),
sideEffects: [addTodoEffect, removeTodoEffect, toggleTodoEffect],
reducer: reducer,
logger: rxReduxDefaultLogger,
);
store.stateStream.listen((event) => print('~> $event'));
for (var i = 0; i < 5; i++) {
store.dispatch(Action(Todo(i, 'Title $i', i.isEven), ActionType.add));
}
await Future.delayed(const Duration(seconds: 1));
for (var i = 0; i < 5; i++) {
store.dispatch(Action(Todo(i, 'Title $i', i.isEven), ActionType.toggle));
}
await Future.delayed(const Duration(seconds: 1));
for (var i = 0; i < 5; i++) {
store.dispatch(Action(Todo(i, 'Title $i', i.isEven), ActionType.remove));
}
await Future.delayed(const Duration(seconds: 1));
}