redex初学

/*
 * action 类型
 */

export const ADD_TODO = 'ADD_TODO';
export const COMPLETE_TODO = 'COMPLETE_TODO';
export const SET_VISIBILITY_FILTER = 'SET_VISIBILITY_FILTER';

/*
 * 其它的常量
 */

export const VisibilityFilters = {
  SHOW_ALL: 'SHOW_ALL',
  SHOW_COMPLETED: 'SHOW_COMPLETED',
  SHOW_ACTIVE: 'SHOW_ACTIVE'
};

/*
 * action 创建函数
 */

export function addTodo(text) {
  return { type: ADD_TODO, text };
}

export function completeTodo(index) {
  return { type: COMPLETE_TODO, index };
}

export function setVisibilityFilter(filter) {
  return { type: SET_VISIBILITY_FILTER, filter };
}

import { VisibilityFilters } from '../actions/actions';

const initialState = {
  visibilityFilter: VisibilityFilters.SHOW_ALL,
  todos: []
};

function todoApp(state = initialState, action) {
  switch (action.type) {
    case SET_VISIBILITY_FILTER:
      return Object.assign({}, state, {
        visibilityFilter: action.filter
      });
    default:
      return state;
  }
}