如何使ListView.builder的itemCount等于FirebaseStorage中的照片数量？

Question

These are my firebase storage images in its 'photos' folder

我正在尝试将在此存储中使用的图像流式传输到Flutter应用中。任何帮助将不胜感激！

Answer 1

我会这样：

Stream<QuerySnapshot> qs = Firestore.instance.collection('photos').snapshots();
int length = await qs.length;

Answer 2

您可以使用StreamBuilder

Stream<QuerySnapshot> qs = Firestore.instance.collection('photos').snapshots();
return StreamBuilder<QuerySnapshot>(
    builder:(context,snapshot){
        if(snapshot.hasData){
          return ListView.Builder(
              itemCount:snapshot.data.documents.length,
              builder:(context,position)=>YOURVIEW()
          );
        }else
          return CircularProgreesIndicator();
    },
    stream:qs
);