title: How do i create a timeline feed using firebase in flutter?
body: <pre><code>- posts
      - userID
      - userID
            - randomID
            - randomID
  - followers
      - personB userid
            - personA userid
  - following 
      - personA userid
            - personB userid
  </code></pre>
  <p>This is how my firebase collection is organized.</p>
  <p>how do i get create a timeline feed for current logged-in user where the timline posts should be of only from the logged-in user's  following list?
  Note:I dont want to use firebase functions.Is it possible with CRUD?
  What ive tried so far.</p>
  <pre><code> getFollowing() async {
      QuerySnapshot snapshot = await followersRef
          .document(currentUser.id)
          .collection('userFollowing')
          .getDocuments();
      setState(() {
        followingList = snapshot.documents.map((doc) =&gt; doc.documentID).toList();
        print(followingList);
      });
    }
    getTimeline()async{
      QuerySnapshot snapshot = await postsRef
          .document(followingList)//getting an error here saying list&lt;string&gt; csn't be assigned to string.
          .collection('userPosts')
          .orderBy('timestamp', descending: true)
          .getDocuments();
      List&lt;Post&gt; posts =
      snapshot.documents.map((doc) =&gt; Post.fromDocument(doc)).toList();
      setState(() {
        this.posts = posts;
      });
    }
  </code></pre>