StreamBuilder gets no data from FireStore | Flutter

Question

In my App, I need to get the Profile-Data of the current user before continuing. I try to accomplish this by using a StreamBuilder in my Code.

My Problem: The StreamBuilder always returns the else statement. As if he cannot load any data from the FireStore-Collection 'Users'.

return StreamBuilder<QuerySnapshot>(
        stream: Firestore.instance.collection('Users').snapshots(), // It seems like he cannot load any data from the collection 'Users'...
        builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot){
          if (snapshot.hasData) {
            print("Loaded data successfully");
            return Container(color: CupertinoColors.systemGreen,); 
          } else {
            print("Could not load data");
            return Container(color: CupertinoColors.systemRed,); // The Code always ends here
          }
        }
      );

Furthermore I don't get any kind of Error-Message.

Flutter Doctor:

[✓] Flutter (Channel stable, 1.20.4, on Mac OS X 10.15.6 19G2021, locale de-DE)
[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
[✓] Xcode - develop for iOS and macOS (Xcode 12.1)
[✓] Android Studio (version 4.0)
[✓] Connected device (1 available)

• No issues found!

Why don't I get any data from Firestore?

EDIT:

My Firestore "Users" Collection (Sammlung):

Image of my Firestore collection

shirsh shukla shirsh shukla · Accepted Answer · 2020-11-09T05:32:57

Try this,

return StreamBuilder(
                stream: Firestore.instance
                    .collection('Users')
                    .snapshots(),
                builder: (BuildContext context,
                    AsyncSnapshot<QuerySnapshot> snapshot) {
                  print("snapshotData"+snapshot.data.toString());
                  if (snapshot.data.toString()=='null')
                    return Container(color: CupertinoColors.systemRed); 
                  if (snapshot.hasError)
                     return Container(color: CupertinoColors.systemRed); 
                  if(snapshot.data.documents.length<1)
                   return Container(color: CupertinoColors.systemRed); 
                  switch (snapshot.connectionState) {
                    case ConnectionState.waiting:
                      return new Text('Loading...');
                    default:
                     return Container(color: CupertinoColors.systemGreen); 
                  }
                },
              );

i am adding condition for blank/null as well.

StreamBuilder gets no data from FireStore | Flutter

2 Answers