如何从扑扑的火力中获取数据 [英] how to get data from firebase in flutter

问题描述

我正在构建一个flutter应用程序并使用cloud-firestore，这就是
，这就是我的数据库的样子，就像

I am building a flutter app and using cloud-firestore, this is how my database looks like

我想要一个函数，该函数在我已经使用过的字符串数组
中检索名为驱动程序列表的集合中的所有文档，但它将其返回到新屏幕的列表视图中

I want a function that retrieves all documents in the collection called "Driver List" in an array of strings that what I had already used but it gets them back in a listview in a new screen

class DriverList extends StatelessWidget {@overrideWidget build(BuildContext context) {
return new StreamBuilder<QuerySnapshot>(
  stream: Firestore.instance.collection('DriverList').snapshots(),
  builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
    if (!snapshot.hasData) return new Text('Loading...');
    return new ListView(
      children: snapshot.data.documents.map((DocumentSnapshot document) {
        return new ListTile(
          title: new Text(document['name']),
          subtitle: new Text(document['phone']),
        );
      }).toList(),
    );
  },
);

}
}

推荐答案

这还有一些其他逻辑，可以删除可能重复的记录，但是您可以使用类似以下内容的方法从Firestore检索数据。

This has some additional logic to remove potentially duplicate records, but you can use something like the following to retrieve data from Firestore.

我们可以访问集合引用，然后列出查询结果，然后为Firestore返回的数据创建本地模型对象，然后返回这些模型对象的列表。

We get access to a collection reference, then list the results of the query, then create local model objects for the data returned by Firestore, and then we return the a list of those model objects.

  static Future<List<AustinFeedsMeEvent>> _getEventsFromFirestore() async {
CollectionReference ref = Firestore.instance.collection('events');
QuerySnapshot eventsQuery = await ref
    .where("time", isGreaterThan: new DateTime.now().millisecondsSinceEpoch)
    .where("food", isEqualTo: true)
    .getDocuments();

HashMap<String, AustinFeedsMeEvent> eventsHashMap = new HashMap<String, AustinFeedsMeEvent>();

eventsQuery.documents.forEach((document) {
  eventsHashMap.putIfAbsent(document['id'], () => new AustinFeedsMeEvent(
      name: document['name'],
      time: document['time'],
      description: document['description'],
      url: document['event_url'],
      photoUrl: _getEventPhotoUrl(document['group']),
      latLng: _getLatLng(document)));
});

return eventsHashMap.values.toList();
}

来源： https://github.com/dazza5000/austin-feeds-me-flutter/blob/master/lib/ data / events_repository.dart＃L33

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