Question

我正在开发一个本机反应项目，我正在尝试使用axios库从api中获取数据并显示数据。所以，我的应用程序首先显示一个启动画面，然后它需要导航到一个页面tab.The选项卡将包含来自api的数据。

所以，我试图在我的主页中初始化我的商店，这是在启动画面之后。我将减速器和动作分别定义在2个不同的文件中。

App.js文件

import React from 'react';
import { StyleSheet, Text, View } from 'react-native';
import { StackNavigator } from 'react-navigation';
import SplashScreen from './src/components/SplashScreen';
import HomeScreen from './src/components/HomeScreen';

const Navigation = StackNavigator({
    Splash: {
      screen: SplashScreen
    },
    Home: {
      screen: HomeScreen
    }
})

export default Navigation;

我的SplashScreen组件：

import React from 'react';
import { StyleSheet,
         Text,
         View,
         } from 'react-native';

export default class SplashScreen extends React.Component {
  static navigationOptions = {
    header: null
  }

  componentWillMount() {
    setTimeout(() => {
      this.props.navigation.navigate('Home')
    },2000)
  }

  render() {
    return(
        <View style={styles.container}>
          <Text style={styles.welcome}>Splash Screen</Text>
        </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: 'skyblue'
  },
  welcome: {
    color: '#FFF',
    fontSize: 30
  }
})

我的HomeScreen组件：

import React from 'react';
import { StyleSheet,
         Text,
         View,
         } from 'react-native';

export default class SplashScreen extends React.Component {
  static navigationOptions = {
    header: null
  }

  componentWillMount() {
    setTimeout(() => {
      this.props.navigation.navigate('Home')
    },2000)
  }

  render() {
    return(
        <View style={styles.container}>
          <Text style={styles.welcome}>Splash Screen</Text>
        </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: 'skyblue'
  },
  welcome: {
    color: '#FFF',
    fontSize: 30
  }
})




import React from 'react';
import { StyleSheet,
         Text,
         View,
         } from 'react-native';

export default class SplashScreen extends React.Component {
  static navigationOptions = {
    header: null
  }

  componentWillMount() {
    setTimeout(() => {
      this.props.navigation.navigate('Home')
    },2000)
  }

  render() {
    return(
        <View style={styles.container}>
          <Text style={styles.welcome}>Splash Screen</Text>
        </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    backgroundColor: 'skyblue'
  },
  welcome: {
    color: '#FFF',
    fontSize: 30
  }
})

Action.js文件

import axios from 'axios';
export const FETCH_DATA = 'fetch_data';

const API = 'https://api.myjson.com/bins/fz62x';

export function fetchData() {
  const request = axios.get(API);

  return dispatch => {
    return request.then((data) => {
        dispatch({
          type: FETCH_DATA,
          payload: data
        })
    })
  }
}

我的减速机

import { FETCH_DATA } from './actions';

export default function(state={}, action) {
  switch(action.type) {
    case FETCH_DATA:
      return {
        ...state,
        action.payload
      };

    default:
        return state;
  }
}

任何人都可以告诉我这是否正确？如果没有，那么正确的方法是什么？

Answer 1

我想说没有正确或错误的方法来做到这一点。但我可以分享一种我经常使用的模式。

首先，我会为不同的文件创建单独的文件夹。 actions文件夹中的操作，reducers文件夹中的reducers等...我会创建单独的constants.js文件和configureStore.js文件，并将它们放在项目根目录中。

我会放弃Axios库，只使用Fetch API进行数据提取。考虑到你的代码，我会做以下事情。

在项目configureStore.js目录中创建root文件。我建议你使用Redux-Thunk。您可以从here找到更多信息。

<强> configureStore.js

import { createStore, applyMiddleware } from 'redux';
import app from './reducers';
import thunk from 'redux-thunk';

export default function configureStore() {
    let store = createStore(app, applyMiddleware(thunk))
    return store
}

<强> App.js

import React, { Component } from 'react';
import { Provider } from 'react-redux';
import { StackNavigator } from 'react-navigation';
import configureStore from './configureStore';
import HomeScreen from './screens/HomeScreen';

const NavigationApp = StackNavigator({
    HomeScreen: { screen: HomeScreen }
})

const store = configureStore()

export default class App extends Component {

    render() {
        return (
            <Provider store={store}>
                <NavigationApp />
            </Provider>
        );
    }
}

让我们创建constants.js，然后将其放在项目root目录中。

<强> constants.js

export const FETCHING_TODOS = 'FETCHING_TODOS';
export const FETCH_TODOS_SUCCESS = 'FETCH_TODOS_SUCCESS';
export const FETCH_TODOS_FAILURE = 'FETCH_TODOS_FAILURE';

现在让我们继续创建我们的操作文件，该文件将放在actions文件夹中。我们将其命名为fetchToDos.js。让我们使用Fetch API创建一个简单的函数。

<强> fetchToDos.js

import { FETCH_TODOS_SUCCESS, FETCH_TODOS_FAILURE, FETCHING_TODOS } from '../constants';

export function fetchToDos() {

    return (dispatch) => {
        dispatch(getTodos())

        return(fetch('https://api.myjson.com/bins/fz62x'))
        .then(res => res.json())
        .then(json => {

            return(dispatch(getToDosSuccess(json)))
        })
        .catch(err => dispatch(getToDosFailure(err)))
    }
}

function getToDos() {

    return {
        type: FETCHING_TODOS
    }
}

function getToDosSuccess(data) {

    return {
        type: FETCH_TODOS_SUCCESS,
        data
    }
}

function getToDosFailure() {
    return {
        type: FETCH_TODOS_FAILURE
    }
}

带Axios的fetchToDos.js

import { FETCH_TODOS_SUCCESS, FETCH_TODOS_FAILURE, FETCHING_TODOS } from '../constants';
import axios from 'axios';

export function fetchToDos() {

    return (dispatch) => {
        dispatch(getUser())
        axios.get('https://api.myjson.com/bins/fz62x')
            .then(function (response) {

                // handle your response here, create an object/array/array of objects etc... 
                // and return it in dispatch(getToDosSuccess(data over here))

                return(dispatch(getToDosSuccess(response.data)))
            })
            .catch(err => dispatch(getToDosFailure(err)))
    }
}

// rest is the same...

继续减速机。让我们创建两个文件 - index.js，todos.js并将它们放在reducers文件夹中。

<强> todos.js

import { FETCH_TODOS_SUCCESS, FETCH_TODOS_FAILURE, FETCHING_TODOS } from '../constants';

const initialState = {
    todos: [],
    isFetching: false,
    error: false
}

export default function todosReducer(state = initialState, action) {

    switch(action.type) {
        case FETCHING_TODOS:
            return {
                ...state,
                isFetching: true
            }
        case FETCH_TODOS_SUCCESS:
            return {
                ...state,
                isFetching: false,
                todos: action.data
            }
        case FETCH_TODOS_FAILURE:
            return {
                ...state,
                isFetching: false,
                error: true
            }
        default:
            return state
    }
}

<强> index.js

import { combineReducers } from 'redux';
import todos from './todos';

const rootReducer = combineReducers({
    todos
})

export default rootReducer

基本上＆＃34;举重＆＃34;已经完成了。我只会创建一个屏幕，因为我们假设用户在主屏幕上点按回按钮（Android），他们最终会在启动画面上显示。所以在这个例子中，我将仅使用一个屏幕。

<强> HomeScreen.js

import React, { Component } from 'react';
import {
    View,
    Text,
    ActivityIndicator
} from 'react-native';
import { bindActionCreators } from 'redux';
import { connect } from 'react-redux';
import { fetchTodos } from '../actions/fetchTodos';

class HomeScreen extends Component {

    componentDidMount() {

        this.props.fetchTodos()

    }

    render() {

        const { todos, isFetching } = this.props.todos

        if (isFetching) {
            return(
                <View style={{flex: 1, flexDirection: 'column', alignItems: 'center', justifyContent: 'center'}}>
                    <ActivityIndicator size={'large'} /> 
                </View>
            )
        } else {
            return(
                <View style={{flex: 1, flexDirection: 'column', alignItems: 'center', justifyContent: 'center'}}>
                    <Text>todos.length</Text>
                </View>
            )
        }

    }

}

function mapStateToProps(state) {
    return {
        todos: state.todos
    }
}

function mapDispatchToProps(dispatch) {
    return {
        ...bindActionCreators({ fetchTodos }, dispatch)
    }
}

export default connect(mapStateToProps, mapDispatchToProps)(HomeScreen)

我真的希望你发现这个概念很有用，因为我可以从我的经验中说，当我第一次开始时它对我帮助很大，它帮助我更好地理解了redux的整个概念。

很抱歉，如果有任何拼写错误和错误。我正在流动。

使用redux

1 个答案: