/**  * This is a state class.  * It can be as simple as possible implementation, like POJO, or immutable object.   */ public class Counter {

  private final int count;

public Counter(int count) {

this.count = count;
  
}

public int getCount() {

return count;
  
}
 
}
  /**  * This is a reducer class.  * It should be applied @Reducer annotation is given a state class as an argument.  * It describe whether the reducer should handle which actions.  */ @Reducer(Counter.class) public class CounterReducer {

/** 
  * This is a method to handle actions. 
  * It should be applied @Dispatchable annotation is given an action class as an parameter. 
  * It describe how to transform the state into the next state when dispatched actions. 
  * It should return the next state instance, and it is preferred instantiate the new state. 
  * 
  * This example handle IncrementCountAction, 
  + and it returns new counter instance that state is incremented. 
  */
  @Dispatchable(IncrementCountAction.class)
  public Counter increment(Counter state) {

return new Counter(state.getCount() + 1);

  
}

@Dispatchable(DecrementCountAction.class)
  public Counter decrement(Counter state) {

return new Counter(state.getCount() - 1);

  
}

@Dispatchable(ClearCountAction.class)
  public Counter clear() {

return new Counter(0);

  
}
 
}

/**  * This is a store interface.  * It should be applied @Store annotation and passing reducer classes as parameters.  * Droidux generates an implementation of getter method, observe method and dispatch method from user-defined interface.  */ @Store(CounterReducer.class) public interface CounterStore extends BaseStore {

  Counter getCounter();

  Observable<Counter> observeCounter();
 
}
  /**  * They are action classes. They should extend Action class.  */ public class IncrementCountAction implements Action {

}
 public class DecrementCountAction implements Action {

}
 public class ClearCountAction implements Action {

}

// Instantiate a Droidux store holding the state of your app. // Its class is generated automatically from Reducer class. //  // The instantiating should use Builder class, // and it should register a reducer instance and an initial state. //  // Its APIs in this example are following: // - rx.Observable<Action> dispatch(Action action) // - rx.Observable<Counter> observeCounter() // - Counter getCounter() CounterStore store = DroiduxCounterStore.builder()

.setReducer(new CounterReducer(), new Counter(0))

.build();

// Counter: 0  // You can observe to the updates using RxJava interface.  store.observe((counter) -> Log.d(TAG, counter.toString()));
  // The only way to mutate the internal state is to dispatch an action. store.dispatch(new IncrementCountAction()).subscribe();
 // Counter: 1 store.dispatch(new IncrementCountAction()).subscribe();
 // Counter: 2 store.dispatch(new IncrementCountAction()).subscribe();
 // Counter: 3  store.dispatch(new DecrementCountAction()).subscribe();
 // Counter: 2  store.dispatch(new ClearCountAction()).subscribe();

  // Counter: 0

// If you use databinding, yor store interface must extend `android.databinding.Observable`. @Store(CounterReducer.class) public interface CounterStore extends BaseStore, android.databinding.Observable {

  // You should annotate the getter method with @Bindable
  @Bindable Counter getCounter();
 
}
  CounterStore store = DroiduxCounterStore.builder()

// Pass the field id generated by DataBinding annotation processor.

.setReducer(new CounterReducer(), new Counter(0), BR.counter)

.build();

@Store({
CounterReducer.class, TodoListReducer.class
}
) class RootStore extends BaseStore {

  Counter getCounter();

  Observable<Counter> observeCounter();

  TodoList getTodoList();

  Observable<TodoList> observeTodoList();
 
}

RootStore store = DroiduxRootStore.builder()

.setReducer(new CounterReducer(), new Counter(0))

.setReducer(new TodoListReducer(), new TodoList())

.addMiddleware(new Logger())

.build();
  store.dispatch(new IncrementCountAction()).subscribe();

  // Counter: 1, Todo: 0 store.dispatch(new AddTodoAction("new task")).subscribe();
  // Counter: 1, Todo: 1

class Logger extends Middleware<CounterStore> {

  @Override
  public Observable<Action> beforeDispatch(Action action) {

Log.d("[prev counter]", String.valueOf(getStore().count()));

Log.d("[action]", action.getClass().getSimpleName());

return Observable.just(action);

  
}

@Override
  public Observable<Action> afterDispatch(Action action) {

Log.d("[next counter]", String.valueOf(getStore().count()));

return Observable.just(action);

  
}
 
}
  // Instantiate store class  CounterStore store = DroiduxCounterStore.builder()

.setReducer(new CounterReducer(), new Counter(0))

.addMiddleware(new Logger())

  // apply logger middleware

.build();

// Counter: 0  store.dispatch(new IncrementCountAction()).subscribe();
 // logcat: // [prev counter]: 0 // [action]: IncrementCountAction // [next counter]: 1  store.dispatch(new IncrementCountAction()).subscribe();
 // logcat: // [prev counter]: 1 // [action]: IncrementCountAction // [next counter]: 2  store.dispatch(new ClearCountAction()).subscribe();
 // logcat: // [prev counter]: 2 // [action]: ClearCountAction // [next counter]: 0

class TodoList extends ArrayList<TodoList.Todo> implements UndoableState<TodoList> {

  @Override
  public TodoList clone() {

// ...
  
}

public static Todo {

// ...
  
}
 
}
  @Undoable @Reducer(TodoList.class) class TodoListReducer {

  @Dispatchable(AddTodoAction.class)
  public TodoList add(TodoList state, AddTodoAction action) {

// ...
  
}

@Dispatchable(CompleteTodoAction.class)
  public TodoList complete(TodoList state, CompleteTodoAction action) {

// ...
  
}
 
}
  @Store(TodoListReducer.class) public interface TodoListStore {

  TodoList todoList();

  Observable<TodoList> observeTodoList();
 
}
  class AddTodoAction implements Action {

  // ... 
}
  class CompleteTodoAction implements Action {

  // ... 
}

TodoListStore store = DroiduxTodoListStore.builder()

.setReducer(new TodoListReducer(), new TodoList())

.build();
  store.dispatch(new AddTodoAction("item 1")).subscribe();

  // ["item 1"] store.dispatch(new AddTodoAction("item 2")).subscribe();

  // ["item 1", "item 2"] store.dispatch(new AddTodoAction("item 3")).subscribe();

  // ["item 1", "item 2", "item 3"] store.dispatch(new CompleteTodoAction("item 2")).subscribe();

// ["item 1", "item 3"] store.dispatch(new AddTodoAction("item 4")).subscribe();

  // ["item 1", "item 3", "item 4"]  store.dispatch(new UndoAction(TodoList.class)).subscribe();
 // => ["item 1", "item 3"]  store.dispatch(new UndoAction(TodoList.class)).subscribe();
 // => ["item 1", "item 2", "item 3"]  store.dispatch(new RedoAction(TodoList.class)).subscribe();
 // => ["item 1", "item 3"]

class FetchTodoListAction implements AsyncAction {

  private final TodoListApi client;

public FetchTodoListAction(TodoListApi client) {

this.client = client;
  
}

public Observable<ReceiveTodoListAction> call(Dispatcher dispatcher) {

return dispatcher.dispatch(new DoingFetchAction())

  .flatMap(_action -> client.fetch())

  .map(todoList -> {

this.todoList = todoList;

return new ReceiveTodoListAction(todoList);

  
}
);

  
}
 
}
  class ReceiveTodoListAction implements Action {

  private final TodoList todoList;

public ReceiveTodoListAction(TodoList todoList) {

this.todoList = todoList;
  
}

public TodoList getTodoList() {

return todoList;
  
}
 
}

TodoListStore store = DroiduxTodoListStore.builder()

.setReducer(new TodoListReducer(), new TodoList())

.addMiddleware(new ThunkMiddleware())

.build();

store.dispatch(new FetchTodoListAction(client)).subscribe();