Problem with showing subcollection from Firebase

Question

I save pictures in Firebase Storage, I save links to them in Firestore, and so on, from Firestore I want to get links and show those pics. I don't know really know where I made mistake. Maybe changing stream will be helpful? Or maybe snapshots? This is the path I save links:

Firestore.instance
          .collection('images')
          .document()
          .collection('others')
          .add({"url": downloadUrl});

Can you please, help me fixing preview of those pictures? I did that with StreamBuilder:

 List<String> listOfUrls = List();
  List<Widget> listOfPics = List();

  @override
  Widget build(BuildContext context) {
    return StreamBuilder(
        stream: Firestore.instance.collection('images').doc.collection('others').snapshots(),
        builder: (context, snapshot) {
          if (!snapshot.hasData)
            return Center(child: CircularProgressIndicator());
          for (int i = 0; i < snapshot.data.documents.length; i++) {
            listOfUrls.add(snapshot.data.documents[i]['url']);
            listOfPics.add(Padding(
              padding: const EdgeInsets.only(top: 50, bottom: 50),
              child: Image.network(listOfUrls[i]),
            ));
          }
          return ListView(
            shrinkWrap: true,
            children: [
              Padding(
                padding: const EdgeInsets.all(8.0),
                child: Text(widget.text),
              ),
              ListView(
                shrinkWrap: true,
                children: listOfPics,
              ),
            ],
          );
        });
  }