redux - 使用 react-redux-firebase 将组件连接到 redux 时选择 firestore 子集合

Question

我在我的 react-native 移动应用程序中使用带有屏幕react-redux-firebase的中间件。fireStoreConnect()在将组件连接到 redux 商店时，我想指定我连接到的 firestore 子集合，这取决于正在导航应用程序的用户。

我应该如何指定集合firestoreConnect？用户 ID 在 redux 存储中。

MWE：

import React, { Component } from 'react';
import { View, Text } from 'react-native';
import { compose } from 'redux';
import { connect } from 'react-redux'
import { firestoreConnect } from 'react-redux-firebase';

class PhotosScreen extends Component {
  render() {
    return (
      <View>
        <Text> i plan the use this.props.images here </Text>
      </View>
    );
  }
}

const mapStateToProps = (state) => {

    // reference the subcollection of the user
    const images = state.firestore.data.images;

    return {
        images: images,
    }
}

export default compose(
    firestoreConnect([
        {
            collection: 'users',
            doc: "HOW DO I GET THE USERS ID HERE? IT IS IN REDUX STORE",
            subcollections: [{ collection: 'images' }]
        }
    ]),
    connect(mapStateToProps),
)(PhotosScreen)

标签： reduxreact-reduxgoogle-cloud-firestorereact-redux-firebase

Answer 1

Firestore（和所有 NoSQL 数据库）遵循交替的“ （父）集合/文档/集合/文档......”分层模式。要将 React 组件与父 firestore 集合下的子集合和文档同步，您需要将子集合/子文档层次结构信息作为 props 传递给firestoreConnect。

    import React, { Component } from 'react';
    import { View, Text } from 'react-native';
    import { compose } from 'redux';
    import { connect } from 'react-redux'
    import { firestoreConnect } from 'react-redux-firebase';

    class PhotosScreen extends Component {
      render() {
        return (
          <View>
            <Text> i plan the use this.props.images here </Text>
            {images && images.length ? <div> render your images here using this.props.images and images.map </div> : <p>No images</p>}
          </View>
        );
      }
    }

    const mapStateToProps = (state) => {

   
        return {
            images  : state.firestore.data.images, // reference the subcollection of the user
            userId  : state.firestore.auth.uid     // assuming the 'doc id' is the same as the user's uid
        }                                          
    }

    export default compose(
        firestoreConnect((props) => 

            if (!props.userId) return []                 // sync only if the userId is available (in this case, if they are authenticated)
            return [
                {
                   collection     : 'users',             // parent collection
                   doc            : props.userId,        // sub-document
                   subcollections : [
                          {collection : 'images'}        // sub-collection
                   ],
                   storeAs        : 'images'
                }
             ]
        }),
        connect(mapStateToProps),
    )(PhotosScreen)