JSON format between Firebase and React Native Flatlist

Question

This is what data are stored in Firebase Realtime Database

"Users" : {
  "Joe" : {
    "name" : "xxx",
    "email" : "xxx"
 },
 "Matt" : {
    "name" : "xxx",
    "email" : "xxx"
 }
}

This is what data need in React Native Flatlist

 Users : [
  {
    id : "Joe"
    name : "xxx",
    email : "xxx",
  },
  {
    id : "Matt"
    name : "xxx",
    email : "xxx",
  }
]

Somewhere in componentDidMount()..

firebase.database("Users").ref().once('value').then(function(snapshot) {
    var arr = _.values(snapshot.val());
    this.setState({ users: JSON.stringify(arr) });
})

In render Flatlist :

   <FlatList
           extraData={this.props}
           data={this.props.users}
           keyExtractor={(item, index) => index.toString()}
           renderItem={({ item }) => (
    ...

How can i use firebase.database().ref() and return what it's look like the data need in flatlist?

Answer 1

You can try something like this:

First in my constructor

constructor(props) {
    super(props);

    this.state = {
        arrData:[]
    };
}

then fetch data from firebase

var ref = firebase.database().ref("Users"); //Here assuming 'Users' as main table of contents   

ref.once('value').then(snapshot => {
    // console.log(snapshot.val());

     // get children as an array
     var items = [];
     snapshot.forEach((child) => {
       items.push({
          id: child.val().id,
          name: child.val().name,
          email: child.val().email,
          phone: child.val().phone,
          status: child.val().status,
          user_type: child.val().user_type

       });
    });

    this.setState({ arrData: items});
});

and now you can populate arrData in your FlatList or ListView.

Hope it helps you!