StreamBuilder Flutter Firebase

Question

I am trying to implement a stream builder to display a String from a firebase document. However I get the following error "The body might complete normally, causing 'null' to be returned, but the return type is a potentially non-nullable type." on the 3rd line of the code. Not sure what I am doing wrong. Any ideas?

    StreamBuilder<QuerySnapshot>(
          stream: _firestore.collection('data').snapshots(),
          builder: (context, snapshot) { 
            if (snapshot.hasError) {
              return const ErrorWidget();
            }
            if (snapshot.hasData) {
              final messages = snapshot.data!.docs;
              List<Text> messageWidget = [];
              for (var message in messages) {
                final messageText = message.get('email');
                final messageWidget = Text('$messageText');
              }
              return Column(
                children: messageWidget,
              );
            }
          },
        )

Answer 1

Add another return after and outside your second if statement. Because currently your streambuilder only returns on two conditions, either error or hasData. But what about everything else? For example waiting?

You can add return CircularProgressindicator() at the end, and it should work.